Troubleshooting Photos –
One Color Dominates The Picture
Problem
The picture seems to be dominated by one color and this dominant color – a color cast – obscures all other colors, making the picture dull and lifeless.
Run your cursor over the buttons to see: (1) the original version with a cast; (2) the cast reduced by making the whole image lighter; (3) the cast virtually eliminated by automatically shifting the whole image toward white; and (4) by adjusting that auto-white image to get warmer tones and more detail, particularly in the cliff face.
What should you look for?
Your initial reaction may be that the picture is simply too dark. Using Levels or a similar command to make the whole photo lighter shows you that there is more to the problem than simple darkness. When the picture is lightened overall, the ice reveals itself to be a bright blue rather than the white we normally think that ice should be.
Why so blue? The photo was taken on what Kodak calls a 'cloudy bright' day in winter, a day when the skylight is shifted even more to blue than normal winter light. This blue is reflected in everything. People don't really notice this blue because our eyes (strictly speaking, our 'vision system', which includes the brain) shift the colors back where we want them to be. Cameras don't make that shift, so the photo looks overwhelmingly blue.
You can see the same effect in sunset photos. Standing on a beach at sunset, you see your friends bathed in a warm and flattering light. The camera, lacking the eye's adaptive qualities, takes a picture that makes their faces as red as stop signs.
This apocalyptic red glare heralded a sudden storm, sending these boats scurrying for home. auto-white was created by clicking on the closest sail with the white eye-dropper in Photoshop Elements' Levels dialog. This makes the clicked-on area white and shifts all colors proportionately. halfway was made by reducing the correction to half the auto-level. They're all interesting, but halfway is probably closer to what people thought they saw that evening.
What should you do?
First, think about what the cast does to the photo. In the picture of the climber, the cast only makes the picture dark and dull, flattening the other colors into the dull grey that makes so many people dislike winter. Accordingly, there is good reason simply to eliminate the cast entirely.
For a sunset photo, on the other hand, you probably want only to reduce the cast, not eliminate it. That gives you back the warm and flattering glow that conveys the happy ambience of the beach. In the storm photo above, the original captured by the camera is so red that it looks like an exposure error, so it's probably best reduced to the halfway version.
How do you fix it?
Most image editing applications now have some sort of automatic color correction function. Depending on the picture, this may work and work well (more on tricking auto-fix functions into doing what you want can be found in About Auto-Correction Tools). The climber picture is well corrected by Photoshop Elements' Auto Color command, probably because there is some white, some black and lots of mid-tones, which gives Auto Color lots to hang its hat on. Take away one of those elements and Auto Color will make assumptions about the picture that can be disastrous.
The storm photo was corrected with Photoshop Elements' Levels command, first by making the sail white (the auto-white version). This takes away all of the flaming red cast that was the point of the photo, making it just a bland picture of some boats. The solution was to go back to Levels and for each of the individual Red, Green and Blue channels (a pull-down menu above the histogram), halve the correction by pulling the white slider back toward the right side, which also moves the mid-tone slider. Unfortunately, this is not an intuitive operation. The picture will change to all manner of horrible colors while you are doing this – you just have to be brave and remember that the effect of moving all three will yield half the difference between the original photo and your auto-corrected one (and remember, you can keep tinkering until you've got what you want as the change isn't permanent until you save the picture.
Moving the white slider (which controls the highlight point) halfway back to its original point produced a photo that is more true to most observers' impression of the scene.
Related topics
More on the use and creative abuse of auto-fix controls is available in About Auto-Correction Tools.
When a cast appears across a range of prints shot under different light conditions, the problem may lie in your color management print settings, particularly if the overall color is shifted to red.
