Another popular selection tool is the Color Range tool. The Color Range tool works on images where the selection is based on color.
Figure 1 shows the Color Range tool (Choose Selections/Color Range). On the right side of the dialogue box are three eyedroppers:
The Invert box option allows the selection to be inverted (i.e., the colors that are clicked are not selected). The Fuzziness slider determines the range of colors that will be selected. A low Fuzziness setting will cause the Color Range tool to select only colors that are very similar to the colors that were clicked. A high Fuzziness setting will cause the Color Range tool to select more colors. The Fuzziness box allows a value for the Fuzziness setting to be typed. Below the image box are two options: Selection and Image. The Selection option (the option that will be used for most photographic work) displays the selection in the image box. The Image option displays the image in the image box.
The Selection Preview Option (see Figure 3) determines how the image will appear.
Don't you wish that everything in Photoshop was easy? For instance, we could tell Photoshop, "I want this color, and this color, and this color. However, I don't want any other colors". Then, we would get exactly what we wanted! Well, perhaps this will be in a future version, but it isn't that easy today. With any complicated selection, it is almost a guarantee that the initial selection will not be perfect. Instead, some areas that are desired will not get selected, some areas that are desired will only get partially selected, and some areas that are not desired will get selected anyway (at least partially). Figure 7 is a perfect example. It was desired to select all of the grass and none of the other areas, but the mask tells a different story. Some of the grass, which should be completely selected, is only partially selected (indicated by the fact that these areas are gray instead of pure white). Some of the non-grass areas, which shouldn't be selected at all, were partially selected (indicated by the fact that these areas are gray instead of pure black).
In order to improve the selection, some clean-up work is usually necessary. For this, clean-up tools are required. This is an appropriate place to introduce these tools. While the Marquee tools, the Lasso tool, and the Polygonal Lasso tool are often used on very simple selections that do not need much, if any, clean-up, the Magnetic Lasso, Magic Wand, and Color Range tools are often used for less simple selections and result in selections that need further work before they are useable. Furthermore, the tools that have yet to be introduced in this series are more advanced selection tools that are usually used with more challenging selections. As a result, clean-up becomes more important with these advanced tools.
Figure 8 shows an image that requires a selection that is challenging. It is desired to edit the sky but not any of the rest of the image. The problem is that the sky and the waves are not easily separated. Any tool that will select at least part of the sky will, likely, also select some of the wave area (at least partially). This is especially true on the right side of the image where the sky and ocean become increasingly close in both color and tone. In addition, in many places, the edge of the wave is actually defined by spray from the wave. These areas have a very poorly delineated edge. This makes the selection even more challenging.
One of the easiest ways to clean-up large areas that need to be either completely selected or completely non-selected is to use the Lasso tool. Figure 11 demonstrates the results of this approach. To capture most of the sky in the selection, the Lasso tool was used to draw around the sky area with the Selection option set to Add To. This ensured that most of the sky was selected. The selection was made as close to the edge of the wave as possible without actually touching the wave.
Figure 14 shows what a mask would look like after the Lasso Tool was used to clean-up part of the non-sky areas. The mask is much improved compared to the original mask shown in Figure 10.
It is important to analyze the mask at this point. It can be seen that most of the sky is totally white, and most of the ocean and beach is totally black. This is as desired. However, along the edge of the wave, some more work needs to be done. There is a gray area just along the edge (this area was selected by the Color Range tool). This gray area is bordered on the ocean side by the rather harsh edge of the black area. This transition is too harsh. In addition, some of the sky just above the wave is partially selected (especially on the right side). This needs to be removed. Lastly, much of this gray area needs to be darkened. For this clean-up, other tools are needed.
In order to better examine the selection, the image is moved into the Quick Mask Mode (click on the Edit in Quick Mask Mode on the Tools palette). Figure 15 shows the image in Quick Mask Mode. To make it easier to see which colors are selected and which are not, the Quick Mask Mode color was changed to yellow by double clicking on the Edit in Quick Mask Mode icon on the Tools palette and clicking on the Color box.
Figure 16 shows a close up of a section of the mask in Quick Mask Mode. It can be seen that part of the wave has been only partly selected. This can be edited in the Quick Mask Mode with the Brush tool.
As seen in Figure 20, the edge of the wave is still a major problem. Any mask made from this selection would, likely, be very noticeable in the image. So, more clean-up is necessary. To proceed, the image is moved out of the Quick Mask Mode (click on the Edit in Standard Mode on the Tools palette), and the selection is turned into a mask (select the layer that is to receive the mask and choose Layer/Layer Mask/Reveal Selection).
Clicking on the mask thumbnail while holding down the Alt key brings up the mask on the screen. Figure 21 shows the mask. Figure 22 shows a close up of a section of the mask.
Now, the mask can be edited directly. For this edit, the Brush tool is selected, the Opacity is set to an appropriate value (this will vary with the image and some experimentation will be necessary to determine the best value), and the Blend Mode is set to Overlay. With the foreground color set to white and the background color set to black, the edge of the wave is painted over with the brush. The edge is painted multiple times alternating the Brush between the background color (black) and the foreground color (white). I have found that it is usually best to start with black. In other words, one pass with a black Brush, one pass with a white Brush, another pass with a black Brush, another pass with a white Brush, and so on.
The secret here has to do with the Overlay Blend Mode. The Overlay Blend mode screens (lightens) the light areas and multiplies (darkens) the dark areas. So, when the brush is white, it will make the light areas even lighter, but it will have much less of an affect on the dark areas. When the brush is black, it will make the dark areas even darker, but it will have much less of an affect on the light areas. Thus, with each successive pair of black/white Brush passes, the contrast increases as the lighter shades progress toward pure white and the darker shades progress toward pure black. For this mask, it is important not to go too far. The edge of the wave should not be too sharp.
If any undesired artifacts remain in the mask, they can simply be painted over with the Brush set to the Normal Blend Mode. A white brush is used to eliminate undesired dark areas and a black brush is used to eliminate undesired white areas.
However, at this point, this mask does not need any touch up with the Brush Tool in the Normal Blend Mode.
Often, no matter how carefully a mask is made, the edges in the mask will be too sharp. This will often be noticeable in an image. Thus, for many masks, the final step is to blur the edges in the mask.
Currently, the mask is open on the screen. While it is possible to directly blur the mask. It is usually better to move back to viewing the image (click on the mask thumbnail while holding down the Alt key). This approach allows the photographer to view how the blurring of the mask is affecting the image.
A close up of the current image (see Figure 25) shows an edge that could be improved by blurring the edge in the mask to produce a more gentle transition from the masked to the unmasked areas (please note that Figures 25 and 28 show close ups of the image, not the mask, and that an extreme Curves layer was added in these figures to brighten the sky in order to make the effects more noticeable). The Blur tool will solve this problem.
To blur the edges in the mask, the Blur Tool is applied to the appropriate area in the image. In other words, the blur is simply painted on (if the Blur tool acts on the image instead of the mask, undo the blur, click the mask thumbnail, and reapply the Blur tool).
Figure 28 shows the image after the blurring of the mask.
At this point, the mask should be closely examined one more time. If any problems still exist, they can be touched up by painting directly on the mask with the Brush. However, this mask does not need any further work.