Assignment • Light & Color
Without light we wouldn't have photography or anything else. Light is life and so true in photography. We talk about Kelvin Temperature which is based upon heating a black object. As the temperature increases we start as a glow and continues to rise in temperature and color. Our primary light source is the sun but there are many other things that create light that we can employ.
Light
The sun is our primary light source. Anything that emits light can be recorded with your camera. Light bulbs, florescent, flash and LED's are considered artificial light. We use artificial light instead of the sun, and sometimes with the sun to fill shadows and reduce contrast.
Your assignment is to take a portrait in full sun. Take one with the sun at your back. Take another shot with the sun to the side and take another with the sun behind your subject, so you are facing toward the sun.
Look at your subjects face in each of the shots. They probably don't look that happy with the sun in their eyes. The image with the sun to the side is easier on your subject but may produce some heavy shadows on the face. When you put the sun behind your subject, called backlighting, and expose for the face, the background becomes much brighter, but then how important is the background? If the background is important to tell a story you can add light to the face with a flash, or with a reflector. Using a reflector or flash will lighten the shadows when contrast becomes too great.
Shooting on cloudy or overcast days lowers contrast as does getting out of direct sun. You can try standing under a tree or in the shade of a building. You may need to reset your WB to a different setting, but you will become a real fan of cloudy days when photographing people.
If you have flash available try taking a shot at sunset with the sunset behind your subject. The light from the flash will be your primary light on your subject with the sunset becoming a background. Bright colors and white work well on your subject.
Your next assignment is to photograph a person inside near a window. Don't use direct sun here. Expose for the bright side of the face and see how the light wraps your subject.
One more shot inside; after dark. Put your subject in a chair or on the sofa near a table lamp. Turn up the ISO and expose for the person and not the light, and don't forget to change your white balance (WB) or everything will be orange.
Your camera will work well inside without additional light. Turn up the ISO and set your WB to the kind of light available. This is a good time to use the manual setting (M). Take your exposure from the light shadows and not from the lights. Most artificial light comes from above. With all automatic settings off, you will be more consistent with correct exposures. Take a test shot to see what you can expect.
Color
You see how red that flower is? It's red because only the red light is reflected to you. All other colors have been absorbed. This is how we see color. We have a blue sky which is an enormous light shade and it tends to push the Kelvin temperature up the scale a bit. The WB is important to getting us close enough to look normal. You can fine tune an image on the computer but each monitor could be different too. Daylight WB setting in the shape of the sun will work for much outdoor shooting.
Emotions play on color, so if your color is way off, you may create a feeling. Blue is blue yet relaxing but it's cold and unpleasant when a warm tone is expected. Having images that break the color mold should be used sparingly unless the effect is part of the story.
Set your WB for daylight. Your first shot(s) will be a candle, or match. Try a couple shots at different exposures. Now do you think you could light a whole room with a candle? If you can see around the room, then the camera should be able to record it too. Turn your ISO up, set your aperture to the widest (ƒ-2.8) using mode A (aperture priority), and expose for an area of the room you wish to see.
The candle will be orange yellow, so now change the WB to the tungsten (the light bulb icon) and take another shot. This is probably closer to true color, but which do you prefer? If you shot a sunset using the light bulb icon, you would lose all the warmth you associate with sunsets. Hey, give it a try. This is a good reason not to use the auto WB setting all the time. Remember color is what we perceive and using a setting that is not correct is not necessarily wrong. Skin tones can look wrong but everything else is negotiable.
So let's take another shot. Find a place with fluorescent lights and set your WB to the fluorescent icon. Set the ISO to 800 and use mode A at ƒ-5.6. Let's get a person in the shot so we can judge skin tones. Indoor lighting fools many people. We want the faster shutter speed or more depth of field but we too often underexpose because we are exposing for the lights and not the subject. Take a couple shots and judge your screen if the scene is light enough. How is your skin color? Probably a little pasty but it should be close. For your comparison shot, change the WB to the daylight icon and try the shot again. Look, you've turned them into martians. There are a lot of different vapor lights that are tough to fix. Probably worse is those orange street lights but they are being replaced by LEDs with a closer to daylight balance.
Daylight, flash, cloudy, and shade are all different balances, but somewhat close. The WB for each adds or subtracts color balance and filtration and they are built into the cameras memory.