Why was Selective Color Correction developed?
Selective Color Correction is an elementary component of reproduction technology and means that only one single color is selected and changed specifically; all other colors remain unaffected. The SCC tool enables selective color correction in a very simple manner. Just one click in the preview window easily selects the color to be changed – it is recognized immediately. From the original color, "warmer" or "cooler" color tones can be selected in a continuous way and their effects on the image evaluated in real time. With this free design option, individual color optimizations and improvements can conveniently be obtained to produce an image that suits the perceptions of the viewer.
How Does Selective Color Correction Work?
The secret of this tool lies in the immediate "recognition" of the selected color nuance and a practical palette composed of 6 or 12 base color variations that can be selected with continuous blending. The entire color palette is available. For more complicated cases, it is also possible to use scalable vector masks on freely defined areas. This permits up to 4 levels – independently from each other – to be subjected to complex color corrections of the same color with different color changes.
Selective Color Correction in SilverFast SE 8 and SE Plus 8
If the overall color balance of a picture should not be changed, but rather just a single color adjusted, Selective Color Correction (SCC) is used. Use of Selective Color Correction is especially practical when one color is contaminated with traces of another. The tool provides access to the six base colors red, green, blue, cyan, magenta, and yellow. For each of these colors there is a menu with preconfigured adjustments and a slider that can be used to change the color value. The color value slider offsets the selected color to one of its neighboring colors on the color circle, that is, for example, red to yellow or magenta, or cyan to green or blue.
Our example image can't simply be neutralized with the pipette because there are no suitable black, white, and neutral points. The approximate neutralization using the image automatic "Shadow cast" and subsequent correction by hand in the histogram highlight our starting image (top left). To allow the flower to stand out more clearly, it and the background must be differentiated from one another in color, that is, the flower should be more clearly yellow and the background more clearly green. The shadowed areas in the background contain a blue and cyan cast. We use the drop-down menu in the line for blue to select "weaker", to reduce the blue in general. Then we select cyan by clicking on one of the squares for processing. We push the H slider upwards to move the cyan portions to the green end, since green is the dominating color of the background and we want to reinforce that even more.
With the H slider for green, we offset the yellow portion of the background a little towards the cyan, allowing the yellow of the flower to contrast better with the background.
Finally, we process the flower. It contains a beautiful yellow that needs no further adjustment. But the yellow is contaminated with red, which can be pushed slightly towards yellow by moving the red H slider. In the result (the image on the top right), the green, out-of-focus background and the yellow flower in focus stand in a clear contrast to one another. This emphasizes the flower as the central element of the picture.
Selective Color Correction in SilverFast Ai Studio 8
In SilverFast Ai Studio 8, the tool window for Selective Color Correction is a little different compared to the SE and SE Plus versions. Here, there are two options for changing colors: a color circle around which the six base colors are arranged, and three sliders for hue, saturation, and relative lightness. This tool offers far more options for selective color correction than in SilverFast SE (Plus).
The dress in the example picture that we want to correct is actually blue. In the photo, though, it seems slightly turquoise, which may be due to the combination of the exposure situation, film material, paper type, and the aging processes. This green contamination in the blue has to be corrected. First, the image should be neutralized with black, white, and mid pipettes or a suitable image auto adjust (top image), then the tool palette can be opened with the "Selective CC" button. Click on the color of the dress to select the turquoise as the starting color for processing, and it is then displayed in the middle of the color circle. To reduce the green contamination, click on the green circle at the top left at the edge of the color circle and pull the color vector carefully towards the middle of the circle. The mouse pointer uses a minus sign to symbolize that the green portion will be removed from the selected color. So the blue of the dress is already restored, but it's still a little washed out.
So we strengthen the blue portion by pulling the color vector from the inner circle outwards towards the small blue circle. In our case, just a slight addition of blue is enough.
The HSL sliders can also be used to carry out this color correction just as easily. Again, first the color of the dress is selected by clicking on it. With the H slider, move the color value from green at the top towards the blue at the bottom.
With the L slider, you can lighten the color up a little, then push the S (saturation) slider up towards a pure blue, which removes a little of the red.
With the very powerful color vectors in SilverFast Ai Studio 8, colors can even be changed entirely. Let's assume you need a picture of a red tulip, but all you have is a purple one. With selective color correction, that's easy to manage. First, click on the flower to select the purple as the color to be processed. Pulling the color vector from the middle of the circle outwards towards the red still looks unnatural. Only after adding a little cyan is the problem corrected and the tulip blossom can shine in a radiant red. Instead of adding a lot of cyan, it would also have been possible to add a little green and a little magenta, or a little blue and a little yellow. The result would have been a red flower in any of these cases, but with very slightly different nuances in the red.