Photography can be a very fun profession or a hobby but you have to understand many of the basics of photography and not let the camera do everything for you in the automatic mode or the program mode in what you think is goof-proof mode!
Light by its very nature is broken up into many wavelengths of color from the visible light spectrum to the infrared spectrum which you really can't see with the naked eye. Remember if you were fortunate enough in Junior High or High School, when the science teacher brought out a prism, and shined light through it and it projected on the wall the colors of the spectrum. We may have learned the colors as: ROYGBIV, Red, orange, yellow, green, blue, indigo and violet! Well, these are continuous colors that blend from one to another and go from warm to cool back to warm again.
In light bulbs of various kinds there are different colors that are given off. You tend to think that a white light is white but this is not so. White light whether in bulb or florescent or other form can have different colors or tints that are given off by the light itself. We don't notice this because our eyes are constantly making adjustments to the colors and how we perceive our surroundings. Our good old incandescent light bulbs generally give off a warm glow in the yellow - orange color range. A florescent light tube can give off cooler colors in the blue to blue-green to the blue-violet ranges. Some lighting in parking lots can have a green coloration. If you use an electronic flash unit on your camera they are generally balanced for fairly close to daylight but can appear cooler (bluer) if you are using them outside against natural daylight.
In our pre digital cameras of years ago, we had to correct for colorations of light depending on whether we were shooting in daylight (outdoors) cooler bluer lighting or in tungsten (indoor lighting) warmer, red-orange or yellow orange lighting. What we basically did the easy way was to buy the appropriate film for the type of shooting that we were doing in that particular session. If we were shooting outdoors we'd generally pick a daylight type film, whether it be a print film or a slide film, (you remember those little pieces of positive film that you'd project from a slide projector before we had digital projectors). Or we would buy tungsten film used for our indoor shooting session where the lighting indoors from a light bulb was generally red-orange or yellow orange. These choices of film generally helped us for average shooting situations.
Another method of color correcting and matching our lighting to a scene or setting was to use filters. Filters are pieces of plastic that are transparent (allowing light to pass through them, but in our case tinting the color of light to match our image or scene. Filters can be bought in sheets that you can cut and hold or attach to the front of your camera lens with the help of filter holders or you can but filters in various thread sizes to fit the front of your lens in varying sizes such as 49mm, 52mm, 55mm, 58mm, 65mm, 72mm, 77mm, etc...
If the scene you shot and the color looked too orange, you would neutralize the color by using a bluish to blue-violet filter and this would make your color look more natural or neutral. If the scene you shot was too bluish you'd generally use a orange filter to make the color more natural or neutral. And if you wanted to go for way out effects you might purposely use different colored filters to make an image warm or cool but that would effect the scene everywhere.
(Your probably asking well how does this info help me today?) Well today most good digital cameras have adjustments on them called white balance or (WB) These settings can be on the top or back of the camera or be found by entering the menu settings on the camera. On Canon cameras after you press menu and toggle through the first or second level of settings you will see (White Balance or (WB). Please check your camera manual depending on your brand of camera! You will usually see icons that are recognizable for Daylight (a sun), cloudy(a cloud), shade(a house with the side of it in shade), tungsten(a lightbulb symbol), florescent (a florescent light symbol), flash(a lightning bolt), etc... or the setting (automatic white balance).This will work ok in some situations but not in all situations. What you should do is first take shots under each lighting condition; in daylight, then use the daylight white balance and view the result on your lcd screen on the back of the camera, then change the white balance to the different settings to see what they will do to your daylight situation. Try going indoors under tungsten lighting then match the white balance setting to the lightbulb icon and take a picture and view your result on the lcd screen! Try changing to all different white balances and view your results.Like anything if you want to fix what you learn from these exercises in your mind, try to put things into your own vocabulary and understanding and perhaps take a memo pad with you and as you try different settings and make yourself a chart and say to yourself: in this lighting condition: ex: daylight, if I use the daylight white balance it will look normal, What will happen when I change to a different white balance? (write down the result)
The real main reason for white balancing is to make your images appear to be neutral (meaning not to warm and not too cool) (Just right). Also you don't want to have your newborn babies skin color to appear green unless he or she is a martian or purple or bluish). One of the other reasons for doing this is you cannot control how your images will view when you connect your camera to other peoples computers and upload images but if you get the color neutral in your camera and your computer you will have more consistency between your camera, computer monitor and eventually your printer as well.
CUSTOM WHITE BALANCE: Most good digital cameras also have a means of creating a custom white balance. Getting into more technical terms: colors can range from warm to cool depending on what is known as the color temperature using the symbol (K) or Kelvin. Warm color Red-Orange within the Visible lighting spectrum may start at 3,200K or 3,200 Kelvin all the way through blueish light 9,000 K or 9,000 (Kelvin) or beyond. Daylight in an outdoor scene might be 5,500K or (Kelvin) to 6,500K or Kelvin, a little close to the middle of the visible light spectrum.
You can buy from a good Photography store, a Kodak gray card. The grey card is 18% middle gray in reflectance and is neutral in color (not too warm and not too cool, right in the middle) and it is of a middle gray tonal value! You should aim your camera at the gray card, filling up the full image area of the frame by viewing the card through the view finder and taking a shot. Remember that when you take the shot of your gray card it must be in exactly the same lighting and position that your subject is in. Try to get a normal contrast reading of the card (a good exposure that looks like the gray card viewing it on your lcd screen). Then within most cameras go to the mode button and in the Area where you found your white balance settings before, look for a selection called custom white balance. If after you have taken the shot, press the custom white balance selection and look for the word set. Once you do this, this shot of your gray card becomes your color balance for every other shot that you take, ensuring a neutral color balance on the rest of your shots, (the shots should have a nice look to them not too warm and not too cool, like the porridge, jut right). Notice if your white areas look white without a color cast (not a tint of yellow or blue) and in the shadow areas, lets say in areas with black in them with no color cast or tint of yellow or blue). Remember that if you were doing these shots at sunset, you'll have warm light areas from the sun and blue or purple shadows. Try to do some of these color balance exercises perhaps between 10:00Am and 2:00 PM where the light may be a little more stable when starting until you get the hang of it!
Remember the color of light changes through out the day, especially as you are shooting before sunrise or coming up on sunset. The color of light generally changes as the sun goes down. The effect may be different depending on whether the light is bending (diffracting) around the clouds or its a clear cloudless day.
I would strongly urge you to look at your camera manual, for setting your custom white balance settings!
Remember that when you take the shot of your gray card it must be in exactly the same lighting and position that your subject is in. If you were shooting a persons face, take a white balance shot with the gray card in front of their face, set the white balance, then in your next shots shoot as usual...
Until we meet again...
I hope this article will be of help to you,
Daniel Johnson
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