Playing With Light Lesson One: How to "See" Light Table of Contents Introduction... 1 Quality of Light... 2 Hard Light... 3 Soft Light... 4 Hard / Soft Blends... 5 Learning to See the Quality of Light... 6 Direction of Light... 6 Portraits... 7 Landscapes... 7 Action... 9 Learning to See the Direction of Light... 9 Color of Light... 10 Color of Light in the Real World... 10 Light Quality and Color... 11 How Your Camera "Sees" Light... 11 Limited Dynamic Range... 12 How to Measure Dynamic Range... 15 Summary... 16 Exercises... 17 Introduction Do you really want to improve the images you take with your digital SLR? There's one very important step required, and it sounds deceptively simple: you need to learn how to see light. Well, duh, right? Every morning when you open your eyes and get out of bed you're seeing light, aren't you? When you go outside on a sunny day, you're also seeing light. But that's not exactly what I'm talking about here. When you're outside walking around - whether you're in the country or right in the heart of a city - you'll see vast changes in the type of light: there's direct light, reflected light, filtered light, partial shade and full shade (just to name a few). A lot of light is pretty "normal" - you see it every day and pretty much ignore it.
But other light is out of the ordinary: it's that light that makes you stop dead in the middle of the street (or the middle of the field) at take a moment to appreciate the scenery in front of your eyes. Now, a huge number of people won't ever stop to appreciate good light because they see it just like they see "normal" light - it doesn't stand out. But once you start actively looking at the quality, direction and color of light around you, you'll soon be able to "see" light in all its various forms. Furthermore, you'll really appreciate it when the perfect light is available right when you want to take some pictures. Quality of Light OK, light-seekers, let's take a closer look at something that we pretty much take for granted: the massive variety of light that we see every single day. We'll begin with an elusive concept: the "quality" of light. Before we start talking about the different types of light that you can run across as you're taking photos, I'd like you to engage in a little visualization exercise. First, imagine that you're sitting on a gorgeous sandy beach. There's not a cloud in the sky and the warm sun overhead is beating down on the water and the sand before you. In this imaginary location, hold out your hand in front of you. In your mind's eye, picture how your hand appears in this scene. Now, change locations: you're looking out a large picture window on a stormy day. It's not raining at the moment, but it's about to. The entire sky is a neutral gray color and there's not a speck of blue in sight. It's daytime, but you have no idea where the sun might be. Stick out your imaginary hand again and picture what it would look like under these circumstances. You've just imagined what I think of as the two extremes when it comes to quality of light: hard light (bright direct sun) and soft light (overcast). Let's take a closer look at these different types of light to see how they impact your photos.
Hard Light When the light is hard there is enormous contrast in the scene - the range of tones from the darkest shadows to the brightest highlights is extreme. The line between light and shadow is sharp - shadows are very pronounced, and are often called "hard" shadows. Here's how different subjects look in hard light: ACTION PORTRAIT LANDSCAPE NATURE As you can see from the examples above, hard light is not very flattering for most subjects. It is harsh and direct, and the hard shadows produced by this type of light either hide important elements in your photo or they distract from your primary subject. Hard light is not ideal for portrait work, since many people - supermodels excluded - don't look good in hard light. Unless you're very careful about how you position your subject, hard shadows can shade the eyes, obscuring the most essential part of any portrait.
A second problem with taking portraits in hard light is that your subject will squint to protect his or her eyes from glare. People who are scrunching up their eyes don't look their best. Landscapes and nature subjects also don't fare well in hard light. The extreme contrast makes it hard for your camera to capture detail in the entire scene - a problem called limited dynamic range, which I'll explain in detail later in this lesson. This is not to say that hard light is not without benefits: while not terribly flattering for portraits and landscapes, hard light is great for action shots. The reason is simple: with all of that light blasting into your camera, it's quite easy to use medium apertures like f/4 and f/5.6 along with very fast shutter speeds (anywhere between 1/1000 and 1/4000). These super-fast shutter speeds can freeze the motion of even the fastest-moving subject: subject motion blur is never a problem when you're working with hard light. Soft Light When the light is soft there is very little contrast in the scene - there's not a huge difference in tonality between shadows and highlights. Shadows and highlights blend seamlessly together - the less intense shadows are also called "soft". Here's how different subjects look in soft light: ACTION PORTRAIT
LANDSCAPE NATURE You should see a fairly substantial difference between these images and the ones captured in hard light. Most notably, the soft light images look better, don't they? There are several reasons why images taken in soft light look better: Soft light photos are not affected by the limited dynamic range of your camera Soft light is more flattering for portrait subjects, and clearly reveals the eyes Since shadows are not as intense as they are in hard light, they are a lot less distracting So there you have it - if you only take pictures in soft light they'll all turn out great right? If only it were that easy. Even though soft light does make your subjects look much more appealing, it comes with its own special drawbacks: Many digital SLR cameras under-expose in soft light (even though the light meter will tell you that the exposure is correct). You have to compensate for this tendency by intentionally overexposing photos you take in soft light. Blurry photos become much more likely in soft light - since there is significantly less available light, you have to use slower shutter speeds in order to get good exposures. Slower shutter speeds make it harder to get crisp action shots and can also cause blur in your portrait photos. Hard / Soft Blends Like so many other things in life, you typically won't just be dealing with the extremes when you're trying to take photos. It's much more likely that you'll be coping with a BLEND of hard and soft light. Mother Nature likes variety, and will throw all sorts of things your way:
Partial Clouds - taking photos on days like this is a real blast any guess why? Well, when the sun dips behind a cloud, you've got soft light and when the sun appears again you've got hard light. Often the light changes quality within a matter of minutes. Atmospheric Haze - on days like this, you're dealing with about 80% hard light and 20% soft light. Shadows will still be quite pronounced, but not as bad as pure hard light. Partial Overcast - a partially overcast day is one where high clouds completely block the sun, but there's no real chance of rain. Under these conditions, you're working with about 70% hard light and 30% soft. Partially overcast days are great ones for outdoor portraits. Learning to See the Quality of Light Now that you have a grasp on the fundamentals of light quality, let's ask the all-important question: how do you learn to SEE it? The most obvious answer here is a common one: take LOTS of pictures in all kinds of light and gradually you'll become more aware of how the quality of light affects your photos. There's also a second approach: take some time to look at the photos other people have taken and posted to sharing sites like Flickr (http://www.flickr.com). When you find an image you really like, try to guess the quality of light: hard, soft, or a blend. As you see more and more images that immediately appeal to you, keep note of the quality of light in each one. You may discover that you have a distinct preference for one type of light. Finally, even if you don't have a camera in your hand or a computer nearby, just pay more attention to the quality of light as you go about your daily business. As you're walking down the street, note how the light on that particular day makes the environment and the people around you appear. and figure out what makes it so remarkable. And, if you happen a spot of really remarkable light (and you should, once you start actively paying attention to it) stop and take a moment to appreciate it. As you did when looking at other people's photos, deconstruct the light Over time, actively looking for great light and taking a moment to appreciate it will improve the images you take when your eye is pressed to a viewfinder. Direction of Light Now that you've got a handle on the quality of light, it's time to pay attention to the direction that the light is coming from.
Like quality of light, the direction of light plays a huge role in your photos and can either complement or distract from your primary subject. When it comes to the direction of light, there are two main things to remember: 1. The Lower, the Better - light that illuminates your subject from straight overhead is not flattering 2. Angled Light Creates Patterns - if the whole purpose of your photo is to capture an interesting pattern, then you need light striking your subject at an angle Let's take a closer look at how these two concepts affect different subjects. Portraits If you take portraits at high noon on a sunny day, you're going to run into a variety of issues that are going to reduce the quality of your image. First, the light is landing on your subject from straight overhead: the eyes fall into shadow underneath the forehead and eyebrows. This problem is compounded if the person is wearing a hat, which can cast a shadow over the entire face. Since the main point of a portrait is to capture the face and especially the eyes, having them in shadow reduces the visual appeal of your portrait. Let's say that your subject isn't wearing a hat, and that you have her tilt her head up a bit so that here eyes are not in shadow. While you've just solved two problems, there's still a third to deal with. Overhead light makes your subject's face look very flat. With the light evenly illuminating the face, there are no shadows to give form and dimension to your image. If you're thinking that taking portraits on a sunny day at high noon isn't the best idea, then you're absolutely right. While I'll go into more detail in a later lesson about how to compensate for this type of light, the simplest thing to do is avoid it altogether. Landscapes The same problems that you'll run into taking portraits in overhead light also apply to landscapes. When you're taking pictures of people, you have to make sure the eyes are not in shadow.
But when the sun is at a very low angle relative to the ground at sunrise and sunset - then all sorts of patterns and textures emerge. If you don't happen to have a desert conveniently located near your home, you can still see the difference between direct and angular light with a simple exercise: 1. Find any object in your home that has a textured surface Since a landscape is a MUCH larger subject you don't have to be as concerned about specific parts of the image falling into shadow. Instead, you have to pay attention to how the highlights and shadows create patterns in your image. 3. Point your camera at the subject and point the flashlight straight at the object (from the same direction as the camera) 4. 5. Move the flashlight so that the light is at an angle to the object When you're taking pictures of a scenic vista, you won't see a lot of pattern and texture in the middle of the day - any time between 10am and 2pm (possibly even longer depending on where you live). The image to the left shows a landscape that looks fairly flat it has some dimension but the entire scene is lit from high above which eliminates texture in the grass and the trees. However, in the early morning and late afternoon, the rays of sunlight strike the landscape at an ANGLE rather than head-on, and the textures created by this angular light result in photos with a LOT more depth. An obvious example of this is the oftphotographed sand dune. With the sun high in the sky, sand dunes will look flat, bland and unimpressive. 2. Get your camera and a flashlight Take a picture 6. Take another picture The image with the angular light will have a lot more texture and depth, and should have a lot more visual punch.
Action When it comes to action photography, waiting around for the light to be just right really isn't an option. If the race car is speeding right at you or the horse is rounding the final turn and coming into the home stretch, it's more important that you get the shot rather than concern yourself with where the sun is in the sky. Therefore, the ONLY thing you can do as an action photographer is to plan ahead. For example, let's say that you're taking pictures of a soccer match at 10am on a bright sunny day. You have no control over the direction of the available light, but you CAN control where you stand to take pictures. You can shoot from either one goal or the other - a few test shots from the first goal makes you realize that all of the player's faces are in shadow. Simply moving around to the other goal will help ensure that the sunlight illuminates the faces of the players, so you can capture some great expressions in addition to all the action. Learning to See the Direction of Light How can you learn to see the direction of light? The answer is pretty simple: pay attention to the shadows. The next time you take out your camera for a few snapshots, take a few shots and then check the images on the LCD to see where the shadows are falling. Better yet: before you take a single photo, take some time to just look at your subject to see if the shadows are problematic. If the shadows are relatively small, it probably means the light is coming from almost directly overhead. While you can take pictures with this type of light, they won't look that great. If the shadows are long, then the light is at a much lower angle relative to your subject. For portraits, you can position your subject so that the light is flattering. For landscapes, YOU have to move around to find the best angle since landscapes can't just "shift a little more to the right".
Color of Light The ability to see the color of light is not a natural one. Here's why: your eyes automatically adjust to all sorts of different colors of light. A bright red rose looks pretty much the same to you whether it's lit by the light of day or by a light bulb in your dining room. But your digital SLR camera sees the world a bit differently. In different types of light and even at different times of day, the "color" of light does change, and this can impact the color of your subject: In the early morning, in shade and in snow, natural light has a blue tint In the middle hours of a clear day natural light is neutral (or white) Toward the end of the day, natural light appears more orange The color of light has a particular impact on portrait photographers - can you guess why? When you look at a photo of a spectacular landscape, it's hard to tell if the colors are an accurate match to the scenery. Since you weren't right next to the photographer who took the picture you don't know what the original colors looked like. But when you look at a portrait photo, you DO know how skin tones are supposed to look. Even if you didn't take the picture yourself, you can immediately tell when the color in a portrait isn't right. Color of Light in the Real World Training your eyes to see the color of light is only possible when you take hundreds of photos in all sorts of different lighting conditions. For example, I've taken landscape shots all the way from early morning to late afternoon. I try to take all my portraits later on in the day (to take advantage of the warmer color of afternoon light) but sometimes - depending on the quality of light - I'll take them right in the middle. I've taken pictures in full sunlight, full shade, at sunrise and at sunset. I've shot under tungsten lights, fluorescent lights and with artificial flash. It was only after several years of snapping pictures (thousands of them) that my eyes began to notice when the color of light changed.
Light Quality and Color The color of light is not only dependent on the time of day - it also depends on the quality of light on any given day. As described above, natural light on a sunny day shifts from blue (or cool) in the morning to orange in the afternoon (or warm). But when the sun is blocked by a thick blanket of clouds, all colors take on a muted appearance that is neither cool nor warm. The best adjective that I can think of to describe colors on an overcast day is "flat". This is both good and bad news for photographers. On the one hand, you don't have to worry about the sun tinting your subject with some odd color cast that you don't want. On the flip side, the colors in the images that you take on overcast days will lack punch. In lesson two, I'll talk about some techniques that can help you compensate for these sorts of lighting conditions. How Your Camera "Sees" Light Now that you have a better sense of the three different aspects of light - quality, direction and color - let's talk about how your camera sees the world differently than you do. To start the discussion, let's take a moment to admire the adaptive qualities of the human eye. Imagine that you're standing outside in the shade of a tree on a bright sunny day with the sun directly overhead. Looking forward, you're not only able to see the grass at your feet, you're also able to make out other trees in the distance and you can tell that the sky is a vibrant blue color. This is because your eyes have exceptional dynamic range. Another way of expressing dynamic range is a measurement called contrast ratio. If you are standing outside on a sunny day, your eyes can perceive a contrast ratio of about 10,000:1. If you step inside a dimly lit room, your eyes will need to adjust, but eventually you will be able to see details in the room. Consider this: with adjustments, your eyes are able to see the world around you when it's lit by bright mid-day sun and even when it's lit by stars on a moonlit night. All together, this could be expressed as a contrast ratio of 1,000,000:1. Keep this number in mind when I tell you that the typical contrast ratio of a digital SLR camera is closer to 200:1. Big difference, isn't it?
Limited Dynamic Range One question that I get a lot from readers of the Digital SLR Guide goes like this: "When I take a landscape picture on a sunny day, if I get the foreground correctly exposed the sky appears pure white in my photo. How can I capture detail in the foreground and also make the sky look blue?" The unfortunate answer is that you can't. The reason is pretty simple: the contrast in the scene is exceeding the contrast range that your camera can capture. When this happens, your camera loses detail in some part of the scene: either the shadows appear very dark (almost black) or the highlights appear very light (almost white). Instead of light and cameras, let's talk about a game of catch. You're tossing a ball back and forth with a friend and - for the sake of this example - you always throw the ball with the exact same amount of force, regardless of where your friend is standing. If your friend moves in close to you, you're going to pitch the ball right over his or her head. If your friend moves too far away, the ball will fall short. Your digital SLR sees light in a similar way: there's only a fixed range of contrast that it can capture. Take a look at the following two diagrams. Diagram #1 shows the range of contrast that you might encounter on a sunny day - the shadows are to the left side of the scale, while the highlights are to the right Diagram #2 shows the range of contrast that your camera can actually capture (in blue) DIAGRAM #1 DIAGRAM #2
When you take pictures under these types of conditions, your camera cannot capture detail in both shadows and highlights. Since the contrast in the scene exceeds the dynamic range of your camera, you're going to lose detail somewhere. Diagram #3 shows what happens when your camera is set to capture details in the shadows - since so many highlights exceed the upper limit, they appear pure white in your photo Diagram #4 shows the opposite: now the details in the highlights are preserved, but those shadows are exceptionally dark, almost pure black DIAGRAM #3 DIAGRAM #4 The following two sample photos illustrate the difference between exposing for shadows vs. exposing for highlights. EXPOSED FOR SHADOWS ISO: 400 Shutter: 1/15 Aperture: f/9 Image #1 shows a scene that includes a bright sky where the camera is set to capture details in the shadows in this case, the grass and the hill in the foreground. While you can see the color of the grass quite clearly, there is little to no detail in the sky.
EXPOSED FOR HIGHLIGHTS ISO: 400 Shutter: 1/400 Aperture: f/9 For image #2 the only change is a faster shutter speed so that the detail in the sky the highlights is preserved. Now you can see the wonderful cloud formations, but the grass and hill in the foreground are one solid black shadow. But what happens when you're not dealing with an extreme contrast range like this? What if you're taking pictures on an overcast day, when the quality of light is soft instead of hard? On an overcast day, the range of contrast in the scene may barely exceed the limits of your camera or it may fall well within the dynamic range your camera can capture. The first diagram and sample image shows what happens when the contrast just barely exceeds the dynamic range of your camera. The second is an example of an instance where the contrast in the scene falls entirely within the dynamic range of your camera. MODERATE CONTRAST LOW CONTRAST The important thing to note is that you can now clearly see details in the shadows and the highlights at the same time. Since the dynamic range in the scene falls within the limits your camera can capture, shadows won't appear dark and highlights won't look bright white.
FULL DYNAMIC RANGE ISO: 400 Shutter: 1/50 Aperture: f/5.6 Thanks to the overhead shade from some very tall trees, the dynamic range in this scene falls well within what a DSLR can capture. This is an example of how shade reduces contrast, but you'd get similar results on an overcast day even if you were standing in the middle of an open field. KEY POINT When the contrast in a scene falls within the dynamic range of your camera, your camera preserves details in BOTH shadows and highlights. How to Measure Dynamic Range Now that you're aware that your camera sees the world differently than your eyes, how can you tell if a scene that you're about to photograph exceeds the dynamic range of your camera? There is a pretty easy test that you can do to find out. 1. Set your camera's metering mode to meter the entire scene (this mode is often called area or evaluative metering) 2. Press down halfway on the shutter release to get a meter reading 3. In manual mode, adjust your aperture and shutter speed so that your meter indicates the scene is correctly exposed (meter is set to zero) 4. Change your metering to center-weighted or spot (if your camera has a spot meter) 5. Without changing the aperture or shutter speed settings, point your camera at a part of the image with shadows and take a meter reading 6. Now point the camera at a part of the image with highlights and take a meter reading If the light meter dips toward -2 when you aim the camera at the shadows and zips up to +2 when you point it at the highlights, the contrast in the scene exceeds the dynamic range of your camera. Let's take a look at an example to see how this works.
First, I make sure that my light meter is set to evaluate the ENTIRE scene (this is the default meter setting for all digital SLRs). I point my camera at the scene in front of me and press down halfway on the shutter release to activate the light meter. Once the meter displays, I adjust shutter speed and aperture to get the meter set to zero (as shown on the right). Now, I change the metering mode to spot (or as close to spot as my camera will allow) and I point it at the brightest part of the scene. I press down halfway on the shutter release to activate the light meter. The meter leaps all the way up to +2. Without changing any camera settings, I point the camera at the darkest (shadow) part of the scene in front of me and press down halfway on the shutter release to take another reading. Now the meter leaps all the way down to -2. This is clearly an instance where the contrast in the scene exceeds the dynamic range of your camera. However, if you only see your meter move around a little bit in between -1 and +1 then chances are that the dynamic range of the scene does NOT exceed the capabilities of your camera. Summary One of the best ways to improve the images that you take with ANY camera has nothing to do with the camera itself. Instead, you have to train your eyes to "see" changes in available light. When you're ready to start taking some photos, take a moment to consider the three important elements of light: 1. Quality - is the light hard (high contrast) or soft (low contrast)? 2. Direction - is the light coming from high above or at an angle? 3. Color - is the time of day having an impact on the color of the light?
Once you're able to quickly assess these three variables, you'll be able to ensure that the available light complements your subject instead of competing with it. Once you become more aware of the available light, you should also have a sense (before testing your hypothesis) whether or not the dynamic range of the available light exceeds what your camera can capture. If there is not a lot of contrast in the scene, then you can rest assured that everything from shadows to highlights will look fine. If there is a lot of contrast in the scene, then you're going to have to take some special steps to handle it. I'll describe some of those techniques in the next lesson. Exercises Exercise 1 Quality of Light To complete this exercise, you're going to need some time, so don't feel rushed to complete it in a couple of days. 1. Pick a subject that you can photograph on a fairly consistent basis: a nearby landscape, flowers in a garden, children, pets, etc. 2. Photograph this subject under every type of natural light: full sun, partially cloudy, somewhat overcast and overcast 3. Photograph at all times of day: morning, noon, evening and night On high-contrast days (full sun at high noon) you'll see what hard light looks like. Note how the shadows appear in your photos and how there is a lot of range between the darkest shadows and the brightest highlights. On days with less contrast (overcast) you'll see soft light: shadows won't be as dominant, subjects will be more evenly lit and there won't be such a huge difference in tonality between shadows and highlights. Over time, you'll learn to identify the type of light without taking a single photo, and this in turn will develop your appreciation for "high-quality" natural light. Exercise 2 Direction and Color of Light This fun exercise will take an entire day to complete, but it's worth it because it will really help you see how the direction and color of light changes over the course of the day. The directions are relatively simple: take a picture of the exact same subject at even intervals from dawn to dusk. Here's some more detail: 1. Pick a subject that is close to home - even in your front or back yard if you've got one
2. Compose your photo - if you have a tripod, mark the spot where you place it so that you can capture your subject from the same angle every time (you want your compositions for every photo you take to be almost identical) 3. Manually set the white balance to "Daylight" (don't leave it on AUTO) 4. Use any camera mode you like (Manual, Aperture Priority, Shutter Priority, etc.) to capture a shot 5. Note the time, and return in one or two hours to take another picture of the same subject 6. Keep taking pictures of the same subject from the same angle until the sun sets If you're ambitious, you can take pictures for 12 hours: from 6am to 6pm. If you're taking one image every two hours you'll wind up with 7 photos. You're welcome to take more, since more images will show changes over shorter intervals. Once you're done, move all the images from the memory card to your computer. Using the image-editing program of your choice, arrange the images so that you can view them one after the other from morning to evening. As you look at each photo, take some time to pay attention to both the direction and the color of the light, and note how both change over the course of the day. Exercise 3 Dynamic Range For this exercise, you're going to need a subject that can be moved around. Any subject will do, it just has to be mobile. You also need to be in an outdoor location where there are trees nearby. Wait to complete this exercise until it is a sunny day. 1. First, place your subject in direct sunlight 2. With the camera meter set to evaluative, adjust shutter speed and aperture so that the meter reads zero 3. Take a few photos with these settings 4. Now change your meter setting to spot (or as close to spot as your camera will allow) 5. Point the camera at the highlights and take a meter reading 6. Point the camera at the shadows and take a meter reading 7. You should see the readings on your camera's light meter jump from +2 to -2 8. Now move your subject right into the very edge of a shaded spot 9. Repeat steps 2 through 6 10. Finally, move your subject into deep shade and repeat steps 2 through 6 again What you should see here is that your meter moves around less and less the deeper the shade. This is because contrast in shade is reduced, and the contrast in the shade will probably fall within the dynamic range your camera can capture. In open sunlight the extreme contrast will exceed the dynamic range of your camera.
What you should see is some loss of detail in the sunny photos either in the shadows or in the highlights (some parts of the photo will either be almost white or almost black). In the photos you take in the shade, you should be able to see plenty of details in both shadows and highlights.