- Color Essentials
- Identifying a Color Cast
- Understanding Color Correction with Image Variations
- Mimicking the Color Darkroom with Color Balance
- Global Color Correction
- The Numbers Don't Lie
- Selective Color Correction
- Alleviating Extreme Color Problems
- Correcting Color Temperature Problems
- Interchannel Color Correction
- Closing Thoughts
Alleviating Extreme Color Problems
Color-correction issues can range from subtle to extreme, and sometimes correcting very bad images may seem like a daunting task. In the following section, you tackle some of the worst color problems quickly and relatively painlessly.
Sometimes an image is so dark or discolored that you're just not sure what to fix first. Should you tackle the density issue or the heavy color cast first? There is not a single solution that always applies, but in many cases images that are both very dark and color contaminated can benefit from the following treatment to remove heavy color casts caused by age, smoke damage, or underexposed images taken in mixed lighting. The photograph in figure 4.82 was taken in 1912. The nine decades that followed made the print darken down and absorb contaminants from the cardboard it was mounted on. Figure 4.83 shows the same image with the undesirable color cast and dark exposure removed.
Figure 4.82 Before
Figure 4.83 After
Open the problem image and add a Levels Adjustment Layer.
Activate the red channel (Cmd + 1) [Ctrl + 1] and move the shadow and highlight levels sliders to where the majority of the information begins, as shown in figure 4.84.
Select the green channel (Cmd + 2) [Ctrl + 2], and move the shadow and highlight levels sliders to where the majority of the information begins, as shown in figure 4.85. Repeat the process on the blue channel (Cmd + 3) [Ctrl + 3] Levels histogram.
If the image requires lightening or darkening, return to the composite histogram (Cmd + ~) [Ctrl + ~] and adjust the midtone slider (to the left to lighten the image, or to the right to darken), as shown in figure 4.86.
Figure 4.84 Moving the red channel shadow and highlight sliders.
Figure 4.85 Adjusting the green and blue channel histograms.
Figure 4.86 Darkening the image by moving the midtone slider to the right.
Extreme Color Correction with Levels
I sincerely hope you never have to work with an image that is as bad as the one in figure 4.87. The original film was poorly stored and processed, resulting in a very dark image with a dominant green cast. In a case like this, the goal is to take the pathetic and create the acceptable, as shown in figure 4.88.
As discussed, identifying the color cast is always the first step in the color correction process. In this case, your eyes would have to be closed not to see the green problem, but take a moment to really look at the image. What is this a picture of? It's a woman standing by a wall. Look againread the image more closelyand look for clues that will help you make the best color decisions. The straw hat and open midriff hint that it's a picture of a woman on a summer day. With that clue, you can imagine that the dress could have been white. Keeping this scenario in mind will guide your color correction. Use your visual memory and color perception to develop a scenario to guide your color correction.
Figure 4.87 Before
Figure 4.88 After
Add a Levels Adjustment Layer. The strong color contamination and tonal problems push the histogram severely to the left (see figure 4.89).
Look for a point in her dress that could be pure white. See how the sun is coming down from the upper left and hitting the edge of her skirt that is in the breeze? Click that with the Levels white eyedropper to remove the color cast, as shown in figure 4.90.
If need be, open up the midtones of the image by sliding the gray midtone triangle carefully to the left (see figure 4.91). In this example, don't worry that her face is still too dark; that is a selective problem and shouldn't be treated while working on the global problem.
Figure 4.89 The Levels histogram is strongly biased to the lefta dead giveaway for a dark or underexposed image.
Figure 4.90 Clicking with the white eyedropper eliminates the color cast.
Figure 4.91 Moving the midtone slider to the left lightens the image.
You can zoom and pan while the Levels and Curves windows are open by using the following command keys:
Pan in the image: Hold down the spacebar to access the Hand tool.
Zoom in: Press (Cmd + Space + click) [Ctrl + Space + click]. (Cmd + "+") [Ctrl "+"].
Zoom out: Press (Cmd + Option + Space + click)[Ctrl + Alt + Space + click]. (Cmd + "-") [Ctrl "-"].
Sometimes it's just easier to start over. When you are working with Adjustment Layers, if you don't like where the color correction is going, you can get back to the original image by pressing (Option) [Alt] to change the Cancel button to Reset. Click and the image will revert to its original settings.