This is a guest post by Nick Vinken. Nick Vinken is a photographer / videographer based in the Netherlands. On his website photographygearguide.com, he shares valuable advice for starting photographers and filmmakers. He mainly discusses gear considerations, but also publishes tips, tutorials and informational articles.

Depth of field (DoF) can be a difficult concept to grasp, but if one understands a few basic concepts it becomes a lot easier to understand and to control. Knowledge of these concepts will help you in improving your photography skills.

Using a shallow depth of field is a powerful tool that you can use to isolate the subject in your frame (either from the background or the foreground). It is a popular style in portrait photography, macro and wildlife photography (among others). When you use a longer depth of field, a larger part of your image will be in focus. This is more useful in other types of photography, like architecture and landscape.

How do you get started with experimenting with “Depth of Field”?

Your camera’s lens will have some point at which it is perfectly focused. There will be a zone of sharp focus both in front of your subject as well as behind it. The zone in front is typically shallower than the zone behind the focal point. There will be a small amount of foreground not in focus, a larger area of background unfocused. Set your camera at A for aperture or M for manual and take control!

You must think about some of these factors as reciprocals to understand the depth of field. There are optical explanations, but you need not know them. The factors that can effect depth of field include:

• Lens aperture the size of the hole that passes light through a reciprocal number.
• Lens focal length the measure of how strongly the system converges or diverges light.
• Shutter Speed the duration for which the shutter is open to transmit light, a reciprocal number.
• Angle of View the width of the view or the scene that the lens can take in.
• ISO the sensitivity to light of the sensor or film.
• Sensor size how large the light sensitive sensor is (in terms of megapixles).

The Lens Aperture (f-number magic)

By setting the lens aperture to a lower number like ƒ2.8-4.0, producing a larger hole in the lens shutter, one creates a much shorter, more compact depth of field (DoF). The background behind the subject will be blurred. This is useful in emphasizing the subject to the exclusion of its surroundings. Especially useful in nature photography: birds, bugs, reptiles and the like-and in portraiture.

Depending upon the ambient light you may need to reduce shutter speed and/or ISO. Setting your aperture to a higher number, say ƒ/22, will produce a smaller hole in the shutter, and give a long depth of field. This is useful for landscapes and can also be used in a lot of architectural shots.

Focal Length and DoF

The effect of focal length on DoF is less dramatic than aperture, but a longer focal length provides a lower optical power and higher magnification. It also compresses the scene front to back, an effect some find desirable. It reduces the angle of view. Setting your zoom to a lower focal length will be associated with a wider angle of view and less DoF.

Other Settings

One may need to make adjustments in shutter speed and/or camera ISO settings to adjust the amount of light passing through the shutter.

Large aperture = more light, small aperture = less light.

So what can you do if your camera does not have these more advanced features? All may not be lost. Check your camera manual and if it has a scene selection group of settings you can use them. The portrait setting will have a shallower DoF, while the landscape setting will have more depth of field. Try these and see how that works for you.

About the author: Nick Vinken is a photographer / videographer based in the Netherlands. On his website photographygearguide.com, he shares valuable advice for starting photographers and filmmakers. He mainly discusses gear considerations, but also publishes tips, tutorials and informational articles.

Focal length, f-number, f-stops — are you set for a little physics on the part of the art called photography?

As much as photography is about capturing the shots with an artist’s eye, it is equally about understanding the science applied in the creation of a photograph.

At a preliminary stage, we hold the camera in the hand and learn to see through the camera’s eye. As we spend more and more time with this awesome machinery (the shot-gun), we tend to learn more about photography like how does the camera work, the essence of drawing with light and the physics of photography.

In the later realm, i.e., the physics of photography, we discover some of the very powerful basics of photography — the focal length,  f-numbers and f-stops. This is what I will demystify in today’s post — the meaning of these mysterious numerals that are almost always found inscribed on the lens barrel of a camera lens.

Let’s take them one by one, starting with the focal length…

What Is The Focal Length?

Theoretically speaking, the focal length of a lens is the distance from the rear element (the glass at the back of the lens) and the point where the light is brought to a focus by the lens, on the camera’s sensor.

The whole idea of having a lens in the camera, you will appreciate, is to project a focused image onto the sensor.

In a true long-focus lens of 200 mm focal length, for instance, this distance will always be 200 mm, necessitating a longer lens barrel. This longer focus has the effect of pulling the subject closer. In other words, magnifying it! But this is dependent on the size of the film or the sensor. An 80mm lens is a short telephoto lens for a camera with an APS-C size sensor, but it is a normal lens for a Hasselblad camera with a larger sensor.

In a normal lens of 50 mm focal length for your full frame DSLR camera, this distance will be found to be 50 mm. Incidentally, this lens is called a normal lens not because other lenses are abnormal, but because the size of the images given by it corresponds to the size of the subject as normally perceived by the naked eye. In other words, the image does not look either reduced or magnified in size (as in the case of telephoto or macro lenses). Many photographers choose to call it the Standard lens.

A telephoto lens, to be exact, is an optically corrected, but physically shorter (i.e., no longer a true long-focus) lens that ensures that the light comes to a focus at the sensor plane. And zoom lens is the one that covers a range of focal lengths for zooming in (getting close) and zooming out (getting away) from the scene.

Over to the next mysterious numeral…

What Is The F-number?

Here’s the secret of the hieroglyphics — the f-numbers engraved on the lens barrel merely indicate the maximum size of the aperture, i.e., the opening allowing the light to squeeze through to get to the sensor after the shutter has been activated.

The maximum aperture is merely a mathematical expression derived from dividing the focal length by the actual, measurable diameter of the front element of the lens.

Try it! Measure the diameter of the front element carefully with a scale. Now divide the focal length of the lens with that number… say, 50 (mm) ÷ 25mm. The answer is 2 and so the f-number or ‘speed’ of the lens is f. 1 : 2 or f 1/2. Voilà! The mystery of the f-number demystified!

Try this — measure the diameter of the front element of the 50 mm f.1.4 normal lens on your fine SLR camera and divide the focal length (50) by it; the answer will always come to be 1.4, which confirms that the diameter of the front element is 50 (focal length) divided by 1.4 = 35.71 mm. This is a f 1 : 1.4 lens – a very fast lens, called fast because it lets in more light and hence allows very short shutter speeds to be used.

A 50mm f.1:1.2 lens is even faster. Actually, the f-number is always expressed (quite correctly) as a ratio, so you will find it inscribed on all but the most basic lenses. The size of the front element usually determines the speed of the lens. That is why the front element of the new Nikon 800mm f 1:5.6 (below) is so massive. This also explains why superfast tele-lenses, mostly used for sports or wildlife photography look like bazookas.

The logic of the f-number — the front lens element relationship is simple — the wider the aperture (here, the front end of the glass where the light enters the camera), the greater is the amount of light reaching the sensor.

It’s no wonder that professionals, who often have to get sharp pictures in poor light, need fast super tele-lenses. These lenses give them as much access to light as possible (and incidentally, enable the fastest shutter-speed possible under the dimly-lit conditions of indoor sports). They usually don’t need much depth of field for a carefully focused news picture in poor light.

If they do need more DOF, they are in trouble. There is no way they can use an aperture of, say, f.8, (giving reasonable DOF, especially with a 500 mm lens and a subject at medium distance), the low shutter-speeds then become obligatory for obtaining a properly exposed image; which will mean the subject, if moving, is going to be badly (probably unrecognizably) blurred. The solution to this issue is presented at the end of this article (hint: a zoom lens with variable f-numbers).

By the virtue of the design compulsions in producing fast lenses, a lot of optical ‘corrections’ are necessary; optical aberrations are unavoidably inherent in designing such lenses. This necessitates many elements inside the lens, busily canceling out each other’s errors. The faster the lens, the bulkier, heavier, and costlier it inevitably is.

In years to come, better, more efficient glasses will be made. Moreover, computer programs and CAD / CAM techniques are constantly improving, so cost and size of lenses are gradually coming down. Yet, an f.1:1.2 lens will always be much more expensive than an F.1:1.8 lens, so if the 1.8 is more than adequate for your needs, it may not be wise to spend more for a 1.2 which will tire you (I mean it, these lenses are heavy), as well as burn a hole in your pocket.

In fact, super-fast lenses are designed in such a way that their best performance (in terms of image quality) comes in at the wider apertures. The whole purpose of buying a fast lens is to use it in poor light or wide open, to get faster shutter speeds, isn’t it? Obviously, the f.1.2, f.2, and f.2.8 aperture settings are going to be used a lot of the time, so the performance at these apertures have to be very good.

This is doubly true because the vast majority of lenses usually perform best when they are used two or three apertures down from maximum aperture. The act of going down the aperture scale, by the way, is called ‘stopping down’. And this brings us to the next question…

What Are F-stops and why do we call them “F-stops”?

The term stops has come to acquire the meaning of one exposure value, or ‘EV’; where each added stop means a factor of two and each subtracted stop means a factor of one-half.

Let us take a simple example to understand the stops. If at 1/125th of a second, you go from f.4 to f.5.6, you have stopped down one stop. This is to say that as the aperture is reduced from f/4 to f/5.6, that is, the aperture is adjusted from lower f-number to the higher f-number in the series sequentially, the exposure value is stopped down by 1EV, thus the term f-stop.

But if you keep the aperture at f.4, and increase the shutter speed to 1/250th of a second, you will again manage to shift the exposure equation one stop!

In other words, adjusting either aperture or shutter speed is expressed informally in terms of stops. Hence, going from f.4 to f.5.6 is equivalent to going from say, 1/125th of a second shutter speed to 1/250th… both of which register the effect that a smaller aperture (more depth of field) or a faster shutter speed (better ability to freeze action, or less visible effects of camera shake) would have on the image.

As this is getting interesting, let’s include one more section here — about variable f-numbers.

Variable F-Numbers

I wonder if you’ve noticed that sometimes the aperture is marked as f.1: 3.5~5.6, say on a 18~300 mm telezoom lens? That little squiggle (~) signifies that the maximum aperture, like the focal length, is variable in actual use, i.e., it varies with the focal length as the zoom lens is zoomed in or out.

It will be a true f.1: 3.5 lens at the shorter focal length (here, 18 mm), but as the zoom is zoomed out, the working aperture will measure out at f.5.6. Intermediate zoom settings will effectively yield intermediate f-numbers.

This is perfectly understandable when we realize that the diameter of the front element remains constant! If the lens remained at f. 3.5 throughout the entire zoom range, it would be very large, heavy and expensive. This is true for all constant aperture zoom lenses.

The two f-numbers mean that the zoom is f/3.5 at the shorter focal length setting, but gradually shifts to f/5.6 as you zoom out to the maximum focal length. To reiterate, this happens because the size of the front element stays constant, as explained earlier.

This also means that as the lens zooms out to 300 mm, the shutter-speed falls by over a stop (all else remaining constant).

If you are setting, say 1/500th of a second from the TTL meter at f/4, the reading will slip to around 1/250th of a second at the 300 mm (f 5.6) zoom setting, provided the intensity of the light and all else remains the same.

Nowadays, computerized flashguns and through the lens flash (TTL flash metering) / TTL auto exposure automatically compensate for the reduced effective aperture, so that we can safely ignore all this; the exposure itself doesn’t suffer!

Remember, each adjacent setting of either aperture or shutter-speed means a difference of one stop, i.e., one notch of aperture or shutter speed. Ditto for ISO sensitivity settings, as visible on the LCD monitor on viewfinder. This is how the exposure triangle works.

And finally, if the minimum aperture (of, say, f.3.5) still does not allow a shutter speed high (fast) enough to stop the action in the low light, you can always increase the ISO setting… the third variable of the exposure equation. In all shooting situations, therefore, the fast lens will always prove more handy than a slow lens.

Author’s Intro: This article is contributed by Subroto Mukerji. Subroto is an amateur photographer of long standing who especially loves to review cameras, lenses, etc. As a passionate hobbyist, he also loves to share his thoughts and insights on various topics related to photography.

I became serious about photography in the late seventies of the last century, well before the dawn of the digital era. A 50 mm f/1.4 ‘standard’ lens was what usually came with the camera, with F 1:1.7 or F 1:1.8 as the cheaper alternatives. After getting my Minolta XE-1 (Ha! Minolta pipped Fujifilm to the post over three decades ago!) and the superfast 58 mm F/1.2 lens that came with it, I went on to acquire, after considerable effort, a 28 mm F/2.8 wide angle and a 100 mm F/2.5 — both original Minolta Rokkor lenses.

While the amazing 58 mm F/1.2 gave me the ability to shoot indoor shots in dim lighting even on Kodachrome 64, the light, small and fast 100 mm tele-lens whetted my appetite for portraiture. Using Kodak Tri-X (400 ASA), I could easily take tight head shots by room lighting, resting my camera on the back of a chair or other steady support.

But I still hankered for greater flexibility when composing my portraits and I soon got lucky with a Hanimex 90~230mm f. 4.5~5.6 zoom lens. It was not very sharp, but in natural light, outside in open shade, I could pull off some great portraits using cine-stock 80 ASA ORWO film rated at 125 ASA, bought in bulk and self-loaded into old 35mm film cans. In fact, the slight softness of the photos was ideal for portraits of ladies and babies!

But I missed the super sharp pictures I always got with the fixed focal length – i.e., ‘prime’ lenses and used the Hanimex only when field compulsions left me with no choice. I finally managed to lay my hands on a Rokkor 200mm F 4.5 telephoto lens, which became my primary (no pun intended) armament for birds and wildlife (till I got a Kalimar 500 mm F 8 mirror lens). All these Rokkor prime lenses were extremely sharp, even wide open. And that is why these prime lenses score over zooms.

Shot With Nikkor 50mm f/1.8 Lens

The Distinguishing Features Of A Prime Lens

1. Prime lenses are relatively small and light: Since they have simpler optical constructions than zooms, primes are lighter and usually smaller and cheaper than zooms.
2. Prime lenses are faster: Thanks to the optical formula of a prime lens, it is usually much faster than a zoom in its category. This also means it is either cheaper or the manufacturer has more leeway to lavish greater optical flourishes on it. The 50 mm F 1.4 Nikkor is well known as one of the sharpest lenses ever made. The latest version, the AFS 50 mm F 1.8G is the best one from the Nikon stables so far, outperforming even the F 1.4 and amazingly, it retails new one for a mere USD 200! No lens ever gave so much quality for so little money.
3. Prime lenses are associated with beautiful bokehs: At the wider apertures (the 50 mm F 1.8 Nikkor gives amazing sharpness from F 2.8 onwards), backgrounds melt away like ice-cream on a hot summer’s day! This enables excellent separation of the subject from the background and makes pictures pop. It is also very handy for food, portrait and product shots, for example, when you need to isolate / highlight a particular feature of a person or an item, throw the rest out of focus.
   

   Shot With AF-S Nikkor 50mm 1.8G Prime Lens

   Bokeh (as the quality of the defocused background is known) is thus a valuable side benefit and a highly prized one at that, which most fast primes confer. Even a fast 24 mm wide angle lens (as you know, wide- angle lenses confer enormous DOF) like the 24 mm F 1.8 Nikkor will de-focus backgrounds if you follow the rules for getting a shallow depth of field.

4. Prime lenses tend to be cheaper: Primes are usually much cheaper to buy than fast zooms. It is only now, in April 2013, that Sigma has released the world’s first F 1.8 zoom (18~35 mm, with F 1.8 aperture being available throughout the zoom range). The 64 million dollar question, however, is how it performs wide open – any modern zoom can give quite decent results at F 5.6, but will that help in low light if you are an inexperienced shooter? Remains to be seen … I’m keeping an open mind till test results come in. A point worth bearing in mind is that this lens weighs about a ton! I’d much rather carry my little 18-55mm kit lens, which is an excellent performer. A trio of 24, 35 and 50 mm lenses would be light and very easy on the shoulder, besides offering great optical quality.

The Downsides Of A Prime Lens

Oh yes, it’s not all milk and roses in fixed-focal-length land. Primes have their downsides, like almost everything else in life… Here we look at the cons – the disadvantages of prime lenses.

• Image stabilization in prime lenses come at a cost: That’s right, buddy, you’re on your own, after being pampered by VC, VR or IS call it what you will. Now you’re at par with old timers like me. VR prime lenses are priced at such a high price that it’s only within the reach of wealthy amateurs, leave behind the common man who can just gaze at these astronomically priced glasses. Example of VR prime lenses — AF-S Nikkor 800mm f/5.6E FL ED VR priced at 22374.739 USD; AF-S Nikkor 200mm f/2G ED VR II priced at 7804.781 USD.
• Changing lenses often results in dust on the sensor: Camera sensors are electrically charged and are magnets for dust. If you tend to change the lenses often in dusty locations then your new dslr will soon be undergoing treatment in the service depot. In film cameras, we just blew dust off the mirror with a blower brush. If dust began to leave scratches on the film, we’d open the back and give it a blast of air as well. Not so today; sensor cleaning is serious business, best left to an authorized service outlet.
• Lack of flexibility: Ken Rockwell, whose sanity if not probity is constantly called to question, says he always keeps his 35 mm f. 1.8G lens on his camera. He advocates we should ‘zoom with our feet’ or work the shot (just a paraphrase) if we need to compose a shot. That’s baloney. Not only does perspective change with distance, I can’t imagine myself walking up to a possible subject (of a candid portrait) in a restaurant and poking my lens in his / her face. Or may be for a distant shot like this one:
  

  Shot With Canon EOS EF 75-300mm f/4.0-5.6 IS USM Zoom Lens

  On the other hand, I’ve often captured great candids with a pocket zoom under the same circumstances. Primes just might be ideal for walkabout street shooting, but I wouldn’t try it. For architectural shots, maybe, but not for people pictures. I should know; I’ve tried both.

Final Verdict — Are Prime Lenses Any Better Than Fast Zooms

That’s my take on the great ‘zoom vs prime’ lens debate. Every time I put my 50 mm f. 1.8G prime lens on my camera, I recall the day when I happened to be 20 feet away when an amazing event took place. An Adjutant Stork, who was being ‘buzzed’ (harassed by sharp, close fly-bys) by a Snowy White Egret suddenly snapped at it and caught it by the beak in mid-air!

Sadly, for some forgotten reason, I had a 100mm lens on my film camera, whereas I needed at least 200mm for a negative with enough detail to produce a winning print. Outcome: I had to trash all the three shots I got. They just couldn’t take the cropping needed for quality prints.

Zoom Lens Shot With A Zoom Lens

Moreover, modern zooms are improving by leaps and bounds, giving photographers enough incentive to jettison their ‘old-baggage’ mindsets about zooms. So, while primes have all the advantages, for me the flexibility of zooms doesn’t allow prime lenses to score over the other. It’s like this — each for its purpose scores; each for its purpose defeats!

What do you prefer — prime lens or a zoom lens?

Author’s Intro: This article is contributed by Subroto Mukerji. Subroto is an amateur photographer of long standing who especially loves to review cameras, lenses, etc. As a passionate hobbyist, he also loves to share his thoughts and insights on various topics related to photography.

Every photographer needs to post process the images; if not always at least on the occasional basis. I am sure they must be using Gamma Correction while correcting exposure of an image in Adobe Photoshop.

Gamma is widely used but rarely understood concept in photo capturing. Technically, it is defined as the relation between a pixel’s numerical value (which is combination of red, green and blue values) and it’s actual luminance (or brightness). Gamma has nothing to do with the photographic process, but it’s badly needed while capturing (in camera) and seeing an image on the screen (to bridge the gap between what a human eye perceive and what the camera captures).

There’s a huge difference between the way camera sees and captures the scene and the way human eyes see and perceive the scene. Logically, twice the number of photons (light rays) hitting the sensor produce twice the signal resulting in twice the brightness.

But the human eyes see twice the light just a little brighter. This is because eye’s sensitivity is greater in darkness than in brightness. While we can still see things in complete darkness, we cannot see in too much of bright light focused at one place. This is where gamma encoding and gamma correction comes into play.

Gamma encoding is a process of encoding the highlights, shadows and mid tones in an image in such a way so that it looks real to human eyes when viewed on the computer screen.

Gamma encoding renders the tones more effectively in an image. If an image is not gamma encoded, the tonal range in it would not be displayed as real shades in the scenes.

When the RAW data is converted to JPEG or TIFF, either in-camera or in RAW editor, gamma encoding is applied to the image to adjust the luminance level as perceived by human eyes. It thus adds a bit more brightness (in layman terms) in under exposed part of the image.

When this image is displayed on computer monitors, the graphic card of the monitor applies gamma correction to the image so that the scene looks almost exactly as it would have appeared to naked eye.

After gamma correction when the human eyes view the image on the computer screen, it looks quite similar to the real scene; with the luminance rendered as per the standard encoding gamma of 1/2.2. The graphical representation for the same is given below.

Gamma encoding and gamma correction is mostly taken care of by either your camera or the RAW editor. However, you can take control of it in Adobe Photoshop with its Gamma Correction feature [Image > Adjustments > Exposure…. Gamma encoding].

This feature comes in handy for redistributing the tonal range of the image uniformly. It thus results in making effective use of bit depth; which otherwise uses more bits to record highlights and lesser bits for shadows.

Technicality of gamma correction and gamma encoding can get quite confusing and is out of the scope of this article. This was just an attempt to convey what gamma encoding and gamma correction is and how it can help improve the images captured by you.

Modern DSLRs have made our life much easier. Most of the manual tasks including a few post-processing effects are now achieved during the shoot itself. One such very important mechanism is auto focus. We see through viewfinder and press shutter release button, the camera automatically focuses on the very first object placed or moving in front of the camera. Have you ever wondered how does camera automatically focus on the subject? Let us take a leap into the optical world and see how actually does a camera auto-focus by itself on the desired subject.

In camera, basically there are two sort of auto-focus mechanism:

• Active Auto Focus
• Passive Auto Focus

Active Auto Focus

Many cameras have active auto focus system, wherein they project electromagnetic waves (such as ultrasonic, visible light or infrared light) onto the subject and record the time of received reflected waves. On the basis of delay noticed between the transmitting and receiving of projected rays, camera mechanism calculates the distance between the camera lens and the subject. And thus it uses this information about the distance to move the lens (forward or backward) of the camera to correctly focus on the subject. This mechanism can calculate the distance between the camera and subject even in complete darkness. However it is not so precise because the camera knows how far is the subject from the camera, but it doesn’t know in which direction the subject is. It can’t focus if the subject is too closely placed such as in macro shots.

• Assist Lamp Auto Focus

  Assist Lamp AF is also distance based and in many cameras it also uses flash light of the camera to reflect light off the subject and calculates the delay in return to estimate the subject’s distance. The disadvantage of this is that if the user overrides the flash settings in a flash operation mode, it also disables the flash used for distance calculation, and it doesn’t work anymore.

• Hologram Auto Focus Laser

  It puts some laser patterns on the subject and reads it to calculate distance. This technology is used in 2003 in Sony Cyber-Shot F707, F717, F828.

Passive Auto Focus

Unlike the active auto focus mechanism, the passive AF is not distance based. It uses electronic analysis in the camera itself to determine whether the camera has focused correctly on an object or not. It basically has two types:

1. Contrast Detection
2. Phase Detection

• Contrast Detection

  It works on the principle that light rays from blurred object are less dense (i.e. have less contrast/subject information) than those reflected off sharp focused object. When the camera tries to focus on an object, it keeps shifting the lens back and front till it gets the peak contrast. The light-intensity (contrast) between adjacent pixels on sensor increases with correct focus. Contrast detection needs some light (and contrast in subject) to work and it cannot work in low contrast situation as in the case of plain scenes like a plain blue sky. Contrast based AF is usually considered accurate, but is slower than phase detection, which we will read about next.

• Phase Detection

  The TTL image (light beams) of an object is split into two separate images with the help of two different micro lenses. Two split images are made to converge onto the auto-focus sensor from the sides of micro lenses. Two different images then fall on two different auto focus sensor. The camera has a pair of auto focus sensors for each auto focus point that you see in the viewfinder. The two images should fall on the center of the auto focus sensor.
  If it doesn’t fall on the center of the AF sensor, the camera keeps tuning the lens back and front till the two images fall on the exact center of the AF sensor. This mechanism can even estimate the degree of focus of an object that has been achieved and its direction. Even this mechanism needs some light to work. Phase detection works faster than the contrast detection auto focus system, but compromises accuracy in favor of speed.

Hybrid Auto Focus

This is achieved by combining the active and passive auto focus to speed up the process and improve the auto focus function. Many cameras of Fujifilm Finepix series and Nikon 1 series use the hybrid auto focus mechanism.

Artificial Intelligence Servo

Auto focus modes in some Canon DSLRs and auto focus continuous (AF-C) in Nikon and Pentax, can predict the future position of moving objects by analyzing their speed and acceleration data. It thus can shoot moving objects with predicted action to a higher degree.

Trap Focus

Trap focus is the focus priority mode in some cameras which can shoot moving objects as soon as they come in the focus plane of the lens (camera) set by user. In many other cameras it is called catch-in focus.

If the camera has active auto focus system, it can be used in darkness as well. During the night many find manual focus easier and beneficial as at night the eyes can see better than camera.

However in adequate light, it is always recommended to use auto focus if the camera has a passive auto-focus system. It is also suggested to use manual focus if you are shooting through a net or something else, where very first object is not actually the desired focused object.

An understanding of the AF system of your camera often comes in handy when in tricky-to-focus scenes. Once you know these, you will be in a better position to understand when to use auto focus and when to focus manually.

The last article “Does amount of light really matter?” invited some valuable comments and brought in some new ways of seeing exposure. Before we delve into the effects, let’s review some of the user comments we received:

I think that amount of light have also a direct impact in color saturation
— Jose

If you have people in a sunset situation, do you want them illuminated or silhouetted? Two very different lighting scenarios with two very different outcomes.
— photoman022

At times the amount of light does matter, others it’s direction, and yet in another situation neither are hinging factors. This may be the mystery and art of photography and the very reason for a lack of a cut-and-dry ‘do it like this’, ‘if-this then-that’ formula to making a great photo.
— Michael

I noticed that after a certain hour afternoon or evening, when the light becomes dimmer the colors loose their vibrance.
— Gavril Margittai

These are just some of the ways of looking at effects of amount of light. Let’s try to understand the relationship of amount of light & Exposure.

As we understand that shooting a photograph entirely depends on the amount of light goes through the lens (TTL) and falls on the sensor of the camera. Now possibly, there can be three kinds of exposure to the sensor of the camera. First is the insufficient amount of light, known as underexposure. Second is more than sufficient amount of light, known as overexposure. And the last is the optimal exposure — the ideal amount of light required to make the exposure.

How Much Is Our Eye Sensitive To Exposure?

Have you ever noticed why our eyes shrink and contract when we suddenly turn on the mercury light bulb in the black dark room? And why our eyes expand and try to open themselves as wide as they can, when we suddenly go into a very dark room from the bright sun light? They try to adjust the exposure by allowing less and more amount of light respectively, into the eyes. If the difference between the intensity of light is less, the iris of our eye adjusts itself for the same. And we don’t even notice these small changes in our eyes. These in fact are unnoticeable.

Camera works pretty much the same way, however even small intensity of light may have noticeable impact on the final image. In the barrel of the lens, there is an opening called aperture. Aperture controls the amount of light that enters the camera and reaches the sensor. The aperture is adjustable. It can be made smaller to allow less light or wider to let more light into the camera. Now how does a camera figure out the amount of light is there in the environment?

How Does A Camera Measures The Amount Of Light?

Camera has a through the lens (TTL) meter, which measures the amount of light entering into the camera. The meter sends the information to the microprocessor of the DSLR. The microprocessor then controls aperture opening, shutter speed and ISO (sensitivity of sensor) in the fashion of reciprocity.

As we know, image is formed on the sensor when light of a particular intensity falls on the sensor for a particular span of time. Shutter is a light proof curtain that guards the sensor against light beams. This span of time depends on the shutter speed; a high shutter-speed means the shutter remains open for a very short time thereby allowing light for a shorter period (or less light in essence). If the shutter speed is slow, it remains open for a longer period of time, eventually letting the light in for a longer period (thus more light gets captured by the sensor). Thus to maintain the correct exposure, if aperture is narrowed down, shutter speed must be reduced to compensate for the shutter’s setting. And if aperture is wide open, the correct exposure can be had provided the shutter remains open for a shorter span of time.

There is one last thing a camera sets to maintain the optimal exposure. This is sensitivity of the sensor itself and is known as ISO. If camera’s ISO is set to Auto, it will increase the sensitivity of the sensor to have correctly exposed image, if either aperture is narrower and also shutter speed is faster, or light intensity (as measured by TTL light meter) is not sufficient despite keeping the aperture wider and also shutter speed slower. Camera maintains the ISO to minimum if there is sufficient light in the scene to make a good exposure.

Thus the correct exposure of the image depends on (three factors) aperture, shutter and ISO. Any one (of the three factors) is proportional to the other factor, keeping the third (remaining one) factor untouched, will give the same exposure. Thus halving one and doubling the other keeps the exposure constant (given everything else remains same). Since there are three elements affecting the exposure viz. aperture, shutter-speed and the ISO, this analogy is often referred to as the exposure triangle.

Overexposure results in brighter midtones and blown out highlights but brings out lot of details from the shadows. Underexposure result in darker midtones, lost shadow details but retains a lot of detail in the highlights.

Many cameras offer various metering modes to calculate the exposure required for a particular scene. However, in essence all this tech-banter ultimately affects the colors, tones and more importantly the dynamic range of the photograph.

Underexposure tends to make everything darker, thus the colors look darker (and visually more saturated). The midtones & highlights in the scene become darker thereby giving the effect of added contrast while the details in the shadows are lost (look at the following images).

Regular Exposure (as calculated by the camera)

Underexposure results in saturated colors.

The degree of “amount of light coming into the scene” vs “the shadow areas” makes up the dynamic range of the scene. However the beauty lies in the fact that given everything else remains constant, just varying the amount of light doesn’t matter.

That’s the magic of the camera — to control the amount of light so it does not affect the exposure.

In the next part we’ll see how various metering modes affect the exposure and how to make the most of it.

We all know how various aspects of light affect the final photograph. Amongst these are temperature, angle, quality (soft vs hard), etc. See Lighting and its features. At the time of writing that article and experimenting whether the amount of light has got anything to do with the final photograph I concluded that changing the amount of light didn’t have any direct impact on the photograph.

However there are other factors at play with respect to the amount of light. The amount of light may not have any direct impact on the output, it definitely presents itself as a constraint around which you, the photographer has to work to make that it’s a good capture. Let’s see how:

Today’s latest cameras, be it the compacts or the DSLRs, are designed to perform at extremely high ISOs. That’s because when you shoot in dim light, ISO comes into play and brings with itself a noise-grain which is not very flattering to the photograph. And once you get this grain, you are left to the mercy of grain removing plugins etc.

That brings in another twist: why do we need flash at all? Guess the amount of light matters after all. May be not in the output itself, but during the capture phase it certainly does (after all photography is about capturing the light).

The exposure triangle is basically trying to control light. While the amount of light may have no direct impact on the end result, it nevertheless is a constraint. Given that you are shooting in low light, the exposure triangle has little control over light (since it is hardly any). You can choose to use slow shutter-speed. But you’d not like the way portraits come out in that setting. Almost always there’s motion blur which needs hours to clear our during post-production.

I’m not asking you to upgrade to a better camera which can shoot in low light. The point is that the amount of light does matter. What do you say?

Image stabilization nowadays is a common feature available even in the compact cameras. The other day I was searching for a compact cameras in Canon Powershot series. And one thing that was common among all the cameras, be it Canon IXUS 510 HS (with 12x optical zoom) or Canon PowerShot S100 (with 5x optical zoom) is Canon’s intelligent IS — a feature that allows steady shots in every situation. While image stabilization is in market for a long time now, I was surprised by the claim “steady shots in every situation”. However you can get sharp and steady shots even without in-camera image stabilization or IS / VR lens (my previous article on how to get razor sharp images has it all).

So what sets image stabilization apart? I did some research to see how image stabilization actually helps in getting the sharp results. Here are some of the facts and myths that I discovered on the go.

But first…

What Is Image Stabilization?

Image stabilization is an awesome feature. It enables you to get crisp and sharp hand held shots. This feature neutralizes the effects of camera shake, if any while taking the shot.

This feature is either built in the camera or the lens. But the key function of this technology is to detect the motion blur caused by camera shake and correct the blurred image projected on the sensor before the sensor converts the image into digital information.

Image stabilization tries to compensate for the hand shakes and image blur common with hand held shooting; especially when shooting in low light (owing to slower shutter speed) or with long lenses (as greater magnification amplifies the blur).

All the major brands have introduced this feature. Some provide it as in-camera feature while others support this feature by incorporating the technology in the lens. Sony’s SteadyShot for instance is a built in camera feature while Nikon & Canon implement this feature through specialized VR (Vibration Reduction) / IS (Image Stabilization) lenses.

How IS / VR Actually Works?

I will try to keep it simple. The lens based image stabilization is implemented by using a floating lens element and in camera stabilization works by sensor shift technology.

In lens based implementation a gyroscopic sensor is used to detect the motion. When the motion is detected the floating lens element offsets the movement by initiating compensatory movement of the lens’s elements.

In sensor based implementation on the other hand, the sensor capturing the image is moved to counteract the motion of the camera; thus the name sensor-shift.

Be it lens-based IS or sensor-based stabilization, this feature simply ensures that the image remains stable prior to its conversion to digital signals.

When Do We Need Image Stabilization?

Image stabilization is factually of no use while shooting either at high shutter speed or slow shutter speed. At a high shutter speed any kind of camera shake or image blur is automatically negated owing to the fast speed of the shutter. And at slow shutter speed as in the case of long exposures the image will always be blurred whatever be the case. Also you will always need a sturdy surface or a tripod when shooting longer exposures.

Barring these exceptions, image stabilization comes in handy when you take hand held shots in low light. As a matter of fact shooting in low light slows down the shutter speed. This means VR or IS comes into play when shutter speed slows down to around 1/2 – 1/15 of a second.

Image stabilization also finds its application while shooting extreme close-ups or when using telephoto lenses. The slightest blur in both these cases can completely ruin the photograph and IS acts as the blessing in disguise.

Can I Use It For Action Or Sports Photography?

Image stabilization by virtue is only designed for and is capable of reducing the blur caused by normal, minute shaking of lens due to hand-held shooting. It however stands ineffective for preventing the motion blur caused by the movement of the subject or by extreme movements of the camera. In fact a fast lens which allows more light in at fast shutter speeds is a better investment for sports photography.

But some of the camera bodies and lenses, my Nikkor 18-200mm VR II lens for instance features an active mode to counteract more aggressive motion blurs; which can also help in capturing the panning shots.

Anyways IS has limited use while photographing action as you are already working with fast shutter speed. At such a high shutter speed, the camera shake is not a critical determinant of sharpness.

Do I Need To Turn IS Off When The Camera Is Mounted On The Tripod?

Yes, the readers manual suggests to turn it off when the camera is mounted on the tripod. This is not a hard and fast rule though. You may get sharp images with IS on or it may also ruin the image. The fact is that when the image stabilization is on, lens anticipates the vibrations in order to counteract the blur. However when it doesn’t detect any motion, it can act in a weird manner to cause the camera shake; thus the result — a blurred image.

But turning the IS / VR on, on a long lens can actually help in eliminating the chances of slight blur caused by wind (when the camera is still set on the tripod). In this case keeping IS on, on the tripod helps. Also the newer lenses are designed to combat this effect. So, please do refer your lens manual to see what does the lens manufacturer suggest.

Is Image Stabilization Worth The Extra Cost?

IS / VR lenses are costlier than their non-IS counterparts. Canon EF 70-200mm f/2.8 L IS for instances costs you around $2199 and its non IS version is currently priced at $1,339 approx. IS is valuable for a lens with such magnification.

Speaking of other lenses in general, you can find your investment in IS / VR lenses safer in most of the cases. If you love to shoot outdoors during the golden magic hour or in the blue hour go for it by all means. An IS lens can substantially improve the quality of your hand-held shots; which happens more often than mounting the camera on the tripod.

I am happy with mine. What about you?

If you’re serious about starting a career in photography, getting your diploma at the photography school is not enough. Even though photography schools play a vital role in imparting the technical theories, there are some things that only experience can teach you — your own experience or the experience of others.

Most of the professional photographers are self learners and have come to take up photography as a profession owing to their passion for making beautiful pictures. I came to realize this fact after interviewing some of the well-known photographers in the industry. Sometimes working as an assistant photographer (like Jim Jordan) pays you off and at other times self learning (Scott MacQuarrie’s approach) is what makes the all difference. Whatever the case be, exhausting all the options help you in defining and refining yourself as a professional photographer.

So while you learn most of the photography basics and fundamentals at photography schools, here are some of the things that you learn when you step in the foot of a photographer.

1. Your Photography Diploma Will Not Get You A Job

   If you think graduating from Brooks or other big names will help you get the job, it’s not necessarily true. Getting started as a commercial photographer really depends on the quality of images you make. Your ability to strike chords by creating eye-catching images is what helps you in establishing yourself as a photographer. In a nutshell, it’s your work and portfolio that works wonders for setting a firm foothold in the market.

2. Be Open To Opportunities, Don’t Stick To A Specific Type Or Genre Of Photography

   Even though photography schools may suggest you to specialize in a particular genre, to succeed as a photographer you should be open to all sorts of opportunities. Photograph more as a generalist and get a fair idea about various types of photography. Nail it down to the photography basics of exposure, composition and lighting & practice the basic fundamentals with whatever the subject be. This will act as a good warmup for establishing yourself as a specialty shooter and will get you started with making decent money as a starter.

3. Work As Assistant Photographer — Step Into The Real World Scenario

   Internship is the industry standard for all sorts of practical oriented vocational courses. Working as an assistant to the photographer in this matter acts as a giant leap. While working with a professional photographer you gain a valuable insight into their photographic workflow — how they get the clients, what techniques do they use, how do they control light and other variables while shooting and all the practical knowledge which you somehow fail to learn in the photography schools.
   

4. Learn From Other’s Work — Copying Ideas Is Not As Bad As It Sounds

   Be original and develop your photographic skills is the kind of idea promoted by photography schools. But there is nothing wrong in copying the ideas of famous photographers. It is when you do so that you discover new techniques and styles. The entire procedure of imitating the works of the masters help you a lot in learning the finer nuances of the art; which ultimately help you in becoming a better artist.

5. You Don’t Always Learn By Taking The Pictures; Get Inspired

   Take picture, take a lot of them, take a few more and practice, practice, practice. Is it the only way to excel in your art? No, you don’t always learn by taking the pictures. You can learn helluva by studying the pictures — be it the photos taken by you or others. Closely observe the details that make a particular image attractive. Or just go through your best pics of all times. Spend some time with your artistic creations — it will charge your creative gears. And then will pave way for a new round of learning — this is what the photography school is all about.

6. Photography Is Not Just The Art Or Technique Of Making Good Photos, It’s Also About Marketing

   Freelancing, editorial photography or commercial photography; whatever you choose as your profession, one requirement that remains constant is that you need to market yourself. Let your potential clients know about you, your capabilities, your charges, your working style, your photographing style and nonetheless give them a reason to consider you for the kind of services you offer. Marketing plays a crucial role in getting the clients. You really need to be versatile at this one — an active social media profile, networking, local advertisements, the portfolio site and good relations with existing customers all work in getting you business — photography projects & assignments.
   

7. It’s Not The Camera, It’s The Photographer

   Latest camera reviews and specs deceive us all in thinking that buying a better camera will help in getting the best images ever. Don’t be fooled by the marketing gimmicks of camera manufacturers — after all it is not the camera but your capabilities and skills as a photographer that shows up in the pictures you make. Check out why your camera doesn’t matter here.

8. Expect The Unexpected — Most Of The Good Photographs Happen Accidentally

   Pre-planning is not the sure shot formula of getting the images you want. You can get some great images even when you are out for a casual photo-walk. The key lesson to take is — keep the camera handy and be ready to photograph the unexpected. Here is an interesting column by Harold Davis where he discloses the secret of making compelling imagery.
   

9. Photography Is An Ongoing Process

   Photography is an ongoing process — you learn as you do and you do what your learn. Trying hands at a new technique for the first time requires you to be thorough with the research and testing. But once you learn the technique, you can easily apply it under various circumstances. This rule applies not only to the technicalities of photography, it comes into foreplay even when building the clientele. You have to plan well for the session and deliver the quality to the first comers. This helps in building the brand for yourself. And once you do so, delivering quality becomes your second nature and your brand becomes the word of mouth for your customers.

10. You Need To Work Your Shots

    Another valuable tip you will never get to learn in the photography school is to work the shots. Working the shots is the pro technique of refining the image by taking multiple shots of the scene by changing the angle of view or by moving closer (or further away) from the subject. Learn more about working the shot here.

Did you miss something in your photography school?

Getting blurred or noisy pictures? Want to reduce this noise and be able to shoot in low-light conditions? Possibly receiving frowns from friends whose portraits you shot? You need a fast lens.

What Is A Fast Lens?

Remember aperture? Aperture is measured in f-stops. The larger the number the smaller the aperture, so f/5.6 is a wider aperture than f/16 — see it is measured in fractions so any arbitrary number f divided by 5.6 will always result in a number greater than the same divided by 16. Enough math. A fast lens is characterized by the ability to allow more light into the camera. This means low ISO (thus low-noise) and faster shutter-speed (since you have enough light, thanks to the wide-aperture).

How Does A Fast Lens Help You

A fast lens becomes critically important when shooting portraits (for me especially when I’m photographing my kid or wife). That saves me from their frowns because it gives clean images with little noise and are sharp (the high shutter-speed reduces the blur). But there’s a hidden bonus too. A wide aperture by it’s very virtue gives me a shallow depth-of-field and a good bokeh. This is reason enough for one to go for a fast lens. A fast lens is best used in portraits since these are the photographs which benefit from it the most (and a landscape will not talk back asking for a better bokeh, neither does it need it). A fast lens also allows one to shoot in low-light conditions with naturally available light like in the evening or indoors.

Examples Of A Fast Lens

Here are the examples of some fast lenses:

• Nikon 50mm f/1.4G AF-S Nikkor Fast Lens
• Canon EF 50mm f/1.2L USM Ultra-Fast Standard AutoFocus Lens
• Sigma 50mm f/1.4 EX DG HSM Auto Focus Lens (available for Canon EOS, Nikon AF-system, Sony Alpha Mount, etc.)

Fast lenses happen to be slightly on the costlier range since they call for so extreme care with the design. But they are well worth the investment, especially if you want to go pro (a pro will already have a fast lens) or want to enhance your portraits. Don’t be surprised if your search for fast lens doesn’t turn up many results on the web; by their very nature, good portrait lenses (and quite many prime lenses) are fast lenses. So look for a good portrait lens which can stop to 1.8, or better 1.4 or 1.2 (the best) f-stops.

For almost all of us be it photographers or the audience, the final result is what matters the most. Capturing a perfect shot every single time is not so easy and thus the flexibility to add finishes to the image in post- processing phase becomes crucial for getting the professional results. Accordingly, the file format you choose to shoot in decides the level of flexibility and control you have over the final result. While RAW format is generally prefered over JPEGs, let’s quickly check out what TIFF format is all about; when and why to prefer (or not to prefer) it over RAW.

Overview — RAW & TIFF

1. RAW: The RAW format is referred to as the digital negative. The RAW format simply preserves the image information as collected by the camera sensor. It is the minimally processed data as captured by the camera sensor and holds information of every pixel of the sensor.
2. TIFF: TIFF is a file format and is an acronym for “Tagged Image File Format”. It is one of the popular formats for high color depth images. The TIFF files usually have either the TIFF or TIF filename extension.

File Size

1. RAW: RAW has a data depth of 12 bit or more. The file size is big and eats up lots of space on your memory card.
2. TIFF: The TIFF normally saves 8 bits or 16 bits per color (red, green, blue) for 24-bit and 48-bit totals, respectively. The file size is even bigger than RAW and the space occupancy is enormous. Thus, buffer is filled up quickly and processing time increases, hindering your capacity to quickly shoot photos one after the other.
   

   2 Pino E La Panchina By mirco_sem (Shot At TIFF)

Flexibility & Versatility

1. RAW: RAW is not readable by all softwares. It is a proprietary format and needs exclusive custom made image editing software for readability for instance Capture NX for Nikon NEFs. Adobe RAW is also a feasible option for RAW files but proprietary software provide much more flexibility and control over the final image. After editing the RAW files, you need to convert them to either JPEG or TIFF for other softwares to read them; especially when you wish to share your work with the publishing industry.
   

   Hamilton Pool Waterfall By Michael Connell (Shot At RAW& Photoshoped)

2. TIFF: TIFF is extremely compatible with most of  the image editing softwares. It is a universal format that is absolutely versatile in its approach. It does not require any proprietary solution for post-processing during or after download from camera, so the image is immediately usable. Also, the ability to store image data in a lossless format makes a TIFF file a useful image archive, because, unlike standard JPEG files, a TIFF file using lossless compression (or none) may be edited and re-saved without losing image quality. However this is not the case when using the TIFF as a container holding compressed JPEGs.

Control Over Post Processing

1. RAW: RAW keeps the information of every pixel intact. It extends the sensor’s dynamic range and provides 256 intensity levels for each pixel. You have a complete control over the image and you can change almost everything (except lighting) like white balance, contrast, sharpness, color saturation, etc. as per your wish.
2. TIFF: TIFF does not have as much editing versatility as RAW. In fact, like JPEG, most of the editing is decided and processed by the camera itself. However, unlike JPEG, since it is an uncompressed, lossless format, therefore, you can do some editing but using the common software editing elements ( like adjusting levels and curves in Photoshop). The parameters and options for editing TIFFs are fixed and limited.
   

   Mare Bagnasciuga By mirco_sem (Shot At TIFF)

RAW or TIFF — Which Format Is Better For Me?

1. RAW: RAW is usually not ideal for beginners. Before using a RAW format, you must make sure why you want to use it. In order to edit RAW files, you must have a high end knowledge, photo-editing skills and an in- depth understanding of the camera as well as the proprietary image editor for RAW files.
   

   Tulip By dougbutchy (Shot In RAW)

2. TIFF: TIFF is considered to be the best for those who do not wish to fiddle much with their images during post-processing. For JPEG and TIFF formats, camera manufacturers input sophisticated, programmed algorithms in their camera sensors for automatically correcting the photographic flaws like contrast, sharpness, color balance etc., in the camera itself.  As such, little needs to be done during the post- processing phase.

Conclusion

We finally arive at the most awaited question — Which format is better [RAW or TIFF]. Well, the answer totally depends on your priorities. If you sweat for fine details and love to deliver professionally finished results, RAW by all means is the piece of cake for you. And if you are looking for a quickly printing the high quality images, TIFF would be an ideal format to shoot in.

A photograph is the photographer’s creation. It is a perfect blend of the photographer’s vision, art and creativity. It is the photographer, his technique and his knowledge which makes all the difference. Just picking up an expensive camera in hand and shooting left, right and centre does no good in getting great images. In fact, a good photograph is the marriage of timing and creativity. Along with a little bit of planning, interpretation of light and compositional rules, some crucial photography decisions help you in getting the photographs you want. Here are ten such photographer’s decisions which will help you take better photographs.

1. What Should I Prefer — Auto Modes Or Semi-Auto Modes

   As a beginner, shooting in the auto mode almost always assures that you get what you want. But as you advance, you can choose to use the specific scene modes, Portrait mode for portrait photography and Night mode for shooting in low-light conditions for instance. And then you can always play around with semi-auto modes like shutter priority and aperture priority modes to get creative with your camera. So if you’re looking for photographing the portrait in context of the environment, turn on the aperture priority mode and choose a higher f-number or turn on the sports mode if you are planning to take dynamic motion shots.

2. When Should I Opt In For Manual Mode

   Switch on the manual mode only when you know what you are doing. The manual mode allows you full control over the exposure. The camera in the manual mode thus allows you to set shutter speed and aperture independently, giving you the ease of taking good shots even in tricky lighting conditions.

3. Trigger Flash Or Turn It Off

   The on-camera flash is a compact and critical source of light a photographer has. But relying on the intelligent machine for firing the flash at the right time is stupid. Owing to the fact that the flash light has it’s own quirks and at times can completely ruin your photographs, it is better to understand when to use flash and when to completely avoid it. Bouncing the flash light off the walls and ceiling in low-light ambience or using it as fill flash when shooting in direct sun makes sense for capturing good shots. Refer to this practical guide on using flash for getting better results with flash photography.
   

4. Burst Mode Or One Single Shot

   If you are all set to capture the liveliness of wildlife, playfulness of your kids and pets or some candid portrait shots, turning on the continuous shooting mode is worth it. And if you’re out there to shoot the still life, pay attention to light, think about the composition and release the shutter for single exposure. So the next time you are planning to shoot a splash scene or freezing the fast action, you know where to bang on! Yes, turn on the burst mode and take instant shots of the subject in action.
   

5. Which format to shoot in — RAW Or JPEG

   The pros advice you to shoot in RAW. The RAW format is analogous to the film negative. The choice to shoot in RAW gives the digital photographers the freedom to focus on photographing the scene creatively than to worry about white-balance, sharpness, colors, saturation in-camera and the likes. JPEGs or the processed images on the other hand call for making precise settings in-camera, deviating you from the basic element of photography — the visualization. It’s your take; if you shoot in RAW, all you need to take care of is to get the light right but shooting in JPEG engages you in taking care of multiple camera-settings. Better solution is to choose RAW+JPEG.

6. Which Focus Mode Should I Choose

   Sometimes you cannot simply rely on the camera’s auto-focus. It plays tricks and focuses on the wrong subject. While using one of the auto-focus modes [Continuous (AF-C) , Single (AF-S), Automatic (AF-A) – Nikon’s auto-focus modes] helps you get the accurate results, still there are some situations where manual focus gives better results. Check out the manual focus mini series on DIY Photography to get an idea when and why manual focus is better than the auto-focus.

7. Hand-held Shots Or A Sturdy Tripod

   With in-built image stabilization feature in most of the cameras and lenses, you can rest assured of decent results if you know how to hold your camera like a pro! But if you are planning to slow down the shutter speed or making long exposures, it is always better to rest your camera on a sturdy surface or pick one of the tripods from this list of unique camera tripods to take your camera to places it simply couldn’t have gone before.

8. Which Lens Should I Use

   Have you ever wondered what do professional photographers carry in their arsenal. Along with the secondary camera, they generally carry a number of lenses for specific scenes and subjects. Knowing which lens is best suited for specific application, for instance using 50 mm prime lens for portrait photography and putting on telephoto lens for shooting the wildlife and birds, helps you in getting the desired effect in the final result. Check out the various types of lenses and their specific application here.

9. How To Get Great Colors: In-camera Or Off-camera

   Getting great yet accurate colors is one thing which goes a long way in making your photographs impressive. While you have the choice of fine-tuning the colors in Photoshop by applying various filters or white-balance presets, adjusting the levels and curves (for correcting the brightness and contrast of the scene) or by playing around with hue, saturation and RGB channels, you can easily get great, real and accurate colors in-camera as well. All it takes to get great colors in-camera is the right time and the right technique. Check out the article titled How To Get Great Colors In-Camera for some handy tips for going the purist’s way of getting unmatched colors in-camera.

10. Photoshopping Or The Purists Approach

    Some photographers get great photographs direct from the camera while other make it “happen” in Photoshop. While the purists love to tune the camera settings, pros generally shoot in RAW and make crucial adjustments like correcting the color cast and fine-tuning the sharpness in post-processing phase. Post-processing gives you a creative edge. In words of Neil Creek, “It’s an extra opportunity to learn more, make better photos and become a better photographer. And to be quite honest, post-processing can be fun! Import your photo, sprinkle a bit of magic ‘post’ dust on a photo, and export something with much more life and impact.”

What decisions help you in taking better photographs?

While reading through one of the popular posts on DPS, one thing that caught my attention was this nifty little idea — shoot fixed focal lengths for kick starting your photography again. As a matter of fact, this is one thing which helps the professional photographers take better images. Owing to its superior optical quality, speed, lighter weight, smaller bulk and lower cost, prime lens is the number one choice of the professional photographers. This reminds me of Henri Cartier-Bresson who used 50mm prime lens for much of his photographic works.

Even though a prime lens takes away the flexibility offered by the zoom lenses, it definitely helps you in becoming a better photographer. And here are 5 reasons why prime lenses help you in composing and taking great shots.

1. Prime Lenses Trigger Thoughtful Composition

   The zoom lens make you lazy. With zoom lens on, instead of moving back & forth and changing the perspective, we love to play around with the zoom ring to compose and re-compose the vision. Thus end up compromising with the creative element of photography — the visualization. The fixed focal length of the prime lens on the other hand acts as the creativity booster. With fixed focal length lens, you already know your camera’s limits & bounds and thus compose the shots with the limited field-of-view in mind. And as Ken Rockwell says, prime lens puts you in compositional seeing mode; the fixed lens triggers the thoughtful composition.

   

   Freedom by T@L

2. Prime Lenses Tend To Produce Sharper Images

   Prime lenses help you in getting clear, crisp and sharp results. This is so because in comparison to a zoom lens, a prime lens has fewer moving parts which are optimized for one particular focal length. With a less complicated lens construction, prime lenses suffer from minimal optical artifacts like distortions at extreme ends of zoom lens range, chromatic aberration and the like.

   

   Fairy Tale by 'J'

3. Prime Lenses Allow Action Stopping Shutter Speeds

   Prime lenses also referred to as fast lenses usually have a larger maximum aperture than zoom lenses. The wider apertures at lower f-numbers enhance the low-light performance and allow for faster shutter speeds which enable you to master the art of action photography.

   

   H 2 Oh!? by laszlo-photo

4. Prime Lenses Allow Narrow DOF & Excellent Bokehs

   Darren Rowse once mentioned that “I love narrow depth of field shots – bokeh is my friend”. Every photographer, be it a beginner or a pro, simply fall in love with the aperture magic. The lower f-numbers (f/1.2, f/1.4) give you an opportunity of framing outstanding photographs — the photographs with selective focus, blurred backgrounds and beautiful bokehs. If you also love to photograph at lower f-numbers, prime lenses are sure to impress you with the amazing results.

   

   Color For A Black & White Day by Nosha

5. Prime Lenses Are Lightweight

   The lightweight of the prime lens has its own advantages over bulky zoom lenses. With small, fixed lenses you are light and mobile and can go on enjoying your photographic excursion. Andrew Gibson counts on it as one of the factors for enjoying photography. Here’s the excerpt from one of his posts, “Another advantage of 50mm prime lenses is that they are very light. This makes a big difference if you’re walking around all day with your camera gear. I’ve made the mistake of taking too many lenses at one time and then being too tired at the end of the day to enjoy taking photos”.

Professional photographers love to photograph and experiment with prime lenses. One such example is Ecstaticist. Check out his collection called A Thousand Drops of Light for some unique examples achieved by using a reversed 50mm prime lens in front of another camera or lens. And don’t forget to share your thoughts on prime lens.

Stereo photography (or stereoscopy) or 3D photography as it is generally referred to as is a lot of fun. It unravels the thrill of visualizing the three dimensional model of the scene captured on 2D photographic frame. Stereoscopy simply refers to a technique for creating or enhancing the illusion of depth in an image.

Photography as an art employs several techniques to add third dimension to the captures. For instance, photographs including varying proportions, perspectives, textures and gradients introduce depth in the photographs but stereoscopy stands out distinct among all the techniques. Stereoscopy enables the viewer to perceive the scene or subject as real life object with an infused sense of 3D view.

Have you experienced this so called illusion of depth? Let’s get straight to it! The magic behind the perception of depth in two dimensional images lies in the principle of stereoscopic vision — the way human beings perceive the world around them with two eyes. The human eyes captures two images of an object, i.e. right eye perceives the angle of view stretching far right and the left eye tries to focus more on the left edge. Our intelligent brain then combines the two views to produce a single image which inherits the depth perception to introduce the sense of three dimensional reality. This principle acts as the founding pillar for stereoscopy or 3D photography.

Just like human eyes perceive two slightly different views of the image and then the brain combines the two images to give the sense of depth, 3D/ Stereo photography uses the stereo pair of images to create the illusion of depth.

Stereo pair is a pair of slightly distinct images placed side by side. It is a pair of two different images, representing two perspectives of the same object, with a minor deviation exactly equal to the perspectives that both eyes naturally receive in binocular vision. The two images are then placed in a tricky manner to hallucinate the viewers to experience the illusion of depth. This is what you have to achieve when shooting the stereo images.

How to shoot stereo images?

There are three distinct ways to shoot stereo images.

1. Using two cameras: Place the two cameras as close as possible and in the same horizontal plane. Tune the cameras with same settings and release the shutter simultaneously. The camera to the left will capture the image as viewed by left eye and the camera to the right will frame the right-eye perspective.
2. With one camera: Place the camera on the tripod and take two shots of the still subject by slightly varying the perspective (in between 1 to 2 inches at the most) without altering the composition and camera settings.
3. Investing in a 3D camera: If you are passionate about 3D photography and your budget allows for this, investing in a 3D camera or the cameras featuring 3D photo mode is a good idea.The 3D cameras helps you in recreating what you wee with your eyes. While 3D cameras out-bursts the 3D feature by providing 3D lens, processor, LCD and advanced 3D modes, the 3D photo mode allows you to take consecutive  shots while panning the camera from left to right (which you can later use to create stereo pair).

After taking the shots, process the images in the image editor targeted at stereoscopic photography. You can proceed with your image editor by placing the images side by side. Place the two images on the same canvas with the shot taken for right eye placed on the right side and the image shot with left eye perspective placed to the left side (as in the following example). This is all it takes to create a stereo pair.

Stereo Pair

How to view stereo images?

It requires a special viewing technique and a little bit of training to experience the illusion of depth. While stereoscopes and 3D glasses makes it fairly simple to view 3D photos, here are two free-viewing techniques which enable you to perceive three dimensional reality without any external aid. The techniques described here contrast with the normal viewing. When you look at an object, the line of sight converge at the same location where the object is placed. The human eyes automatically adjust the line of sight and point of convergence to produce an image of the object and send signal to brain. When viewing the stereo pair of images, you have to employ special techniques and view beyond or before the point of convergence to visualize three dimensional imaginary view of the scene in the stereo pair.

1. Parallel Viewing: Parallel viewing, also known as divergence is the technique where you maintain a parallel line of sight. This is to say that your left eye is focusing on the left image and right eye is focusing on right image. As you keep staring at the images, you will get double vision because each eye is now trying to focus on both the images individually. You will thus be able to view four blurred images of which the middle ones will overlap to form a stereo image. Hold the line of sight and concentrate on image formed in the center to visualize three dimensions in the image. You can try it out with this stereo pair of the Cathedral.
   

   Try viewing left image with left eye and right image with right eye

2. Cross Eye Technique: If you are not able to visualize 3D with parallel viewing you can try out with cross-eye technique. Unlike parallel viewing, in cross-eye technique you need to view the left image with right eye and right image with left eye. You can use the tip of a pen or pencil to help you cross the eyes. Place a pen horizontally in between the two images and try to focus on the tip. As you concentrate on the tip of the pen you will slowly observe that the two images overlap to form a third image in the center. The center image is stereo. Focus on the center image so that you get a clear three dimensional vision. Try the cross eye technique with this stereo pair of orchids.
   

   Try cross viewing: look at right image with left eye and left image with right eye

Note: It is difficult to visualize the stereo effect at the very first instance. If you managed to view the stereo image in the first go, congratulations! If you were not able to visualize, don’t lose heart. It just requires a little bit of practice to train your eyes to visualize the 3D effect.

Have fun and enjoy the thrill of 3D visualization. And watch out this space for some great stereo pairs to train your eyes to visualize the illusion of depth. Other than enjoying the 3 dimension reality in photographs, this is a great exercise for the eyes too!

Color management is the essence of reproducing accurate color information. As much as it is required for attaining color consistency across devices more it gets complicated with each person preferring specific color profile and working space for color managed workflow. While we have taken this topic earlier as well for introducing color management, color spaces and working spaces, this post is dedicated towards various issues, queries, facts and myths about color management. Get started with your specific query.

• Should I shoot in sRGB or Adobe RGB?
• Which color space should I use for printing?
• Why are my prints dark?
• Why is the color shifted?
• Why is ProPhoto RGB preferable working space for photographers?
• Why use ProPhoto RGB when the monitor cannot display it and printers can’t print it?
• Which is better — Adobe RGB or ProPhoto RGB?
• Why do Adobe RGB 1998, ProPhoto RGB (non-sRGB) photos look dull/unnatural on my monitor?
• Which one is a better option — Color space conversion or using sRGB?
• What’s the difference between Assigning Color Profiles and converting into color profiles?
• Capture NX2: Working Space vs Color Mode
• I don’t need color management. I just use the standard monitor and printer.
• If I set my working color space to ProPhoto RGB, my photos will have richer gamut/colors.
• I use Adobe RAW/Lightroom and I get perfect colors from my NEF RAW files.
• Having images with the correct profile will make them show right on my monitor.
• Working in ProPhoto RGB is a waste as one can’t even see what colors they are affecting?
• I need ProPhoto RGB!
• What’s the ideal color-managed workflow?

1. Should I shoot in sRGB or Adobe RGB?

Majority of DSLRs provide the option for selecting either sRGB or Adobe RGB. The option only has effect on JPEG images, RAW format as such does not have a color profile (since RAW is not even an image, it’s pure data). Nikon’s specification on choosing the color space at the time of shooting thus recommends to:

• Choose sRGB for photographs that will be printed or used as it is without any further modifications. This is to say that if you want to primarily use the images for viewing on-screen (on your computer and share over internet) you can safely opt for sRGB, the standard color space.
• Choose Adobe RGB for images that will be extensively processed or retouched after leaving the camera. This means Adobe RGB should be preferred when you are preparing your photographs for prints because of the larger color gamut of Adobe RGB.

2. Which color space should I use for printing?

Depends on the gamut of your printer. If you are lazy, just let the printer manage your color profile settings/conversion. If you are using a commercial printer or sending the images to lab you may want to check with the lab. Most of the new inkjets can cover the Adobe RGB gamut. So if you have an image in Adobe RGB, by all means go for the Adobe RGB profile. But if your image itself is in sRGB, don’t bother with anything wider or bigger.

Working Spaces

3. Why are my prints dark?

This is the most common question posted on the photography forums. Most of the people complaint that the colors in the prints are darker than what they see on their screens. This depends on several factors:

1. Monitor Calibration And Soft Proofing Profile: The problem with monitors is that they can be set to any brightness or contrast level. So if you have set your monitor to be very bright you are not viewing the actual brightness of the image. Monitor calibration is thus the first step in the color management workflow. This is a crucial step in ensuring color consistency across the devices. With regard to monitor calibration, to preview the actual result you need to calibrate your monitor in accordance with the target settings. If your aim is to emulate the prints, you will need to set the white point (ideally D65 to start with) and luminance (in the range of 120-140 cd/m²) accordingly. Once you have calibrated the device in accordance with the target medium, soft-proof the printers profile to preview the print results.
2. Print Viewing Condition: If you view the final prints under varying light conditions, the results vary. If you view the prints in low ambient light, the prints are sure to appear dark whilst day light viewing. So it is important that you view the prints in the similar lighting as your printing workstation. If even then the results vary, it reflects that something has gone wrong with monitor calibration itself.
3. Missing Color Profile: When issuing the print command the color management was turned off. For true colors to be output, the color management must be enabled either in the software or the printer itself. Turning off color-management will also result in a color-shift.

Refer to the article why are my prints too dark by Andrew Rodney for a better insight and technical explanation of the problem.

4. Why is the color shifted?

The color shift simply means that the colors of the image are changed when viewed on various devices. This happens due to one of the following reasons:

1. No Color Profile Embedded: If you do not tag the color profile to the digital image it is sure to lack color consistency across the devices and thus a difference in color values when viewed on various output devices. Embedding the color profile to the image solves the problem. Using the color-aware / color-manged applications like Photoshop enables you to assign and embed the color profile to the images.
2. Ignoring The Color Profile: When you ignore the image’s embedded color profile, the color managed application assigns it the default profile resulting in clipping the color information lying outside the color gamut of the assigned profile, resulting in a color shift.

To ensure that there is no color shift, always use a color managed application and ensure that the application asks for your consent over ignoring, assigning / converting or embedding the required color profile. For instance you can specify the color management policies in Photoshop for missing profiles and profile mismatches to ensure that the color profiles are handled appropriately. By default Photoshop preserves the embedded profiles. Follow the given steps to verify the color management policies in Photoshop.

1. Go to Edit > Color Settings or press Shift+Ctrl+K to open color settings dialog.
2. Under Color Management Policies section, make sure that RGB, CMYK and Gray are set to Preserve Embedded Profiles.
3. Check the Profile Mismatches and Missing Profiles options (ask when opening and ask when pasting). This will ensure that when you open an image file, Photoshop will ask you to either ignore, assign (convert) or embed the color profile.

5. Why is ProPhoto RGB preferable working space for photographers?

ProPhoto RGB offers an especially large gamut designed for use with photographic output in mind. Even when the color gamut of ProPhoto RGB cannot be fully reproduced by any output device, it is recommended working space for photographers. The primary reason for choosing ProPhoto RGB as the working space is its ability to contain all the original colors captured by the camera in RAW format. Using a wider color space ensures that there is no color loss. With ProPhoto you can also retouch to exaggerate and artificially induce the ProPhoto RGB colors (but that requires a lot of expertise and there’s no reason why one would need to). However if your original image is anything smaller than the ProPhoto RGB gamut then don’t bother with ProPhoto.

6. Why use ProPhoto RGB when the monitor cannot display it and printers can’t print it?

Even when the color gamut of ProPhoto RGB cannot be reproduced on the output devices, ProPhoto RGB is preferable owing to two facts:

1. Preserve Color Information: Especially when shooting RAW, the camera sensor collects the color information which is practically out of color gamut of any working space. Using the working space with largest color gamut is clearly a winner in retaining and preserving the colors which are otherwise clipped and lost when you shoot in sRGB or Adobe RGB.
2. Effective Mapping Of Color Information: After assigning ProPhoto RGB as the working space you can easily convert the image to either sRGB or Adobe RGB. When converting the image from a wider working space to a smaller working space the color information is not clipped. In fact the colors are mapped to match with the destination color space and thus reproduce true and accurate colors within the limited color gamut.

Assigning ProPhoto RGB also comes in handy for maintaining a master copy of the image. With the advancement in technology we may sooner or later come across the devices with extended Adobe RGB capabilities and thus reproduce ProPhoto colors as well. It is however important to note that when working with larger color gamuts it is recommended to work with 16 bit color information or else you may run the risk of posterization or banding (which may also occur when you convert from smaller gamut to wider one).

7. Which is better — Adobe RGB or ProPhoto RGB?

Adobe RGB was designed with the intent of reproducing the true colors in print. This was achieved by extending the color capability of sRGB towards the cyan and green in three dimensional color model to come up with an RGB color space which fully contains CMYK model. Adobe RGB is as such preferable color space for printing for commercial purposes. Also with the advancement in printing technology and evolution of inkjet printers supporting 8 to 12 inks it is possible to output Adobe RGB color gamut in prints. This characteristic of Adobe RGB makes it a highly realizable color space as against ProPhoto which encompasses 100% real-life colors along with 13% imaginary colors (lying outside the range of visual primaries). Still then ProPhoto is widely used by the photographers to preserve the RAW color data captured by the camera sensor.

8. Why do Adobe RGB 1998, ProPhoto RGB (non-sRGB) photos look dull/unnatural on my monitor?

This simply happens because the application you are using for viewing the images is not color managed. This may happen in Photoshop as well if it is set to discard embedded profiles. If you really like to have a choice of profile when opening an image, turn on the Profile Mismatch and Missing Profile options “Ask when opening” and “Ask when pasting” to ensure that Photoshop prompts you to ignore, convert or use embedded color profile whenever you open the image (or assign the profile to the image with missing color profile).

9. Which one is a better option — Color space conversion or using sRGB?

We have been talking a lot about color space conversion in the preceding paragraphs. The question thus arises that when we have to ultimately convert the image into sRGB color space, is it not better to use sRGB throughout the workflow. If you shoot mainly for internet then sRGB is optimal. However if you want to print, you’ll get richer colors with ProPhoto RGB or Adobe RGB  based workflow.

10. What’s the difference between Assigning Color Profiles and converting into color profiles.

Assigining color profiles to images is a “sin”. Unless you have an image with a missing profile or you are very sure of it’s color-profile only then should you assign it a profile. Incorrect assignment results in a color-shift.

Conversion between color-profiles is a process wherein a source color-profile is mapped into a target color-profile retaining as many colors as possible and thus maintain the color integrity. During the conversion the subtle color detail is preserved and mapped effectively to render true colors to the photograph.

11. Capture NX2: Working Space vs Color Mode

When working with Capture NX2, color management becomes much more confusing. Besides RGB color spaces, Nikon also offers the color modes to select from. Nikon offers five color modes namely Mode I, II, III, Ia and IIIa. These color modes should not be confused with working spaces. These color modes are simply variations in combinations of RGB primaries to reproduce rich greens, reds or magenta. As per the usage terms, Mode I is desirable for portraits and Mode III is designed to render vivid colors especially rich greens more suitable for landscapes. Still both the modes are output sRGB color gamut with slight difference in the saturation level of hues, while Mode II is true Adobe RGB.

The working spaces on the other hand define the color gamut you can use for retouching an image. If you use this gamut, you must save into a target profile that can contain this gamut.

12. I don’t need color management. I just use the standard monitor and printer.

If you use a standard monitor and a printer and you never take or send these images to anyone and you find the colors accurate and you have no interest in complicating things, just use sRGB (or ignore color management). Due to the number of conditions in the previous statement, it is rare that you have such an environment to absolutely warrant a workflow free of color-management.

13. If I set my working color space to ProPhoto RGB, my photos will have richer gamut/colors.

Working space defines the set of colors which can be utilized for post-processing the image. Also just converting to the ProPhoto RGB doesn’t make a difference since it will not expand the small gamut into a wider one. Working space is meant to retain colors in images which have a wider color gamut.

14. I use Adobe RAW/Lightroom and I get perfect colors from my NEF RAW files.

This is not true. Put another way, the colors may be to your liking but they are not technically accurate (the actual colors that existed in the scene). NEF is a propietary RAW format and RAW doesn’t have a color-profile. Only the camera (or Nikon Capture NX2) knows the color curve of which Adobe has no clue. Adobe created camera profiles for many of these cameras in it’s lab and distributes them via the updates to Adobe RAW. Nevertheless, the moment you underexpose or overexpose, the colors are gone for a toss and can only be accurately reproduced if you shoot TIFFs or JPEGs or if you use Capture NX 2.

15. Having images with the correct profile will make them show right on my monitor.

It depends on the software you using to view the image is color managed or not. Windows and Mac are not color managed. They rely on the color managed applications to render accurate colors.

16. Working in ProPhoto RGB is a waste as one can’t even see what colors they are affecting?

Working in ProPhoto RGB is not a waste of time. Other than the benefits it has, you can actually visualize the colors you are editing. Photoshop’s advanced color management settings allows you to desaturate the colors to visualize what’s getting affected. Note that this helps you only visualize what’s getting affected. It however doesn’t display the actual colors as the monitor you are using to view the image outputs sRGB color gamut or Adobe RGB at the most. Remember, ProPhoto RGB is not meant to help you see extreme colors, it’s meant to help you retain the widest color gamut possible in your images. You can then convert them down depending on the target media.

17. I need ProPhoto RGB!

You may or you may not. If you can’t tell the difference between the ProPhoto RGB, Adobe RGB and sRGB variants of a colorful photograph, you are better off sticking to sRGB.

18. What’s the ideal color-managed workflow?

1. Shoot RAW.
2. If using NEFs use Capture NX or View NX to convert the RAW data to images and use Color Mode II (which is Adobe RGB — the widest gamut you can extract from NEFs while retaining true colors). For other non-proprietary RAW formats, Adobe RAW works well and use ProPhoto RGB.
3. With either of these profiles use a color depth of 16bpp.
4. After you are done with post-processing,  convert the images to the destination color-profile.
5. Finally you may want to convert them to 8 bits. The order is important as reducing to 8 bits before profile conversion will result in banding. (Read why this artifact occurs in our previous post on working space comparison sRGB vs Adobe RGB vs ProPhoto RGB.)

If you still have some unanswered queries about color management, feel free to add to the list.