Forward and Back
Extracting elements from images is not necessarily an end point. While it may prove useful to extract a single element from a single image to just copy and paste it to another image, that is only one of the many possibilities offered by the extract tool. By making isolating image elements somewhat easier and quicker to accomplish, partial extractions may prove useful in improving image color and texture as well.
This holds true in the example. With the extractions completed, it was easier to control the color of the petals and the color of the center of the flower. While your choices may be different for improving the look of this image, the example is meant to show you the type of thing extractions might be useful for. I felt the color could be better: the yellow looked a little dull and the petals too flatly toned. With the center extracted the color and dimension of that area can easily be improved. A levels correction on the first extraction can bring out some detail that is in the image, but hidden by the flat tone of the petals. I took the several additional steps once the extractions were complete to improve on the flower starting with just the 2 layers from the extraction. You can see the resulting layers in the finished image by downloading it here: Finished Image.
1. Duplicate Extraction 2.
2. Move the layer to the top of the layer stack.
3. Change the Blend Mode of the duplicate of Extraction 2 to Color Burn. This improves the yellow.
4. Add a slight drop shadow and bevel using Layer Styles to give the elements at the center of the flower a little more depth.
5. Duplicate Extraction 1.
6. Apply Levels color correction to build more contrast in the flower petals.
7. Apply a Hue/Saturation Adjustment layer to the Levels corrected Layer (from step 5) to shift the color back to the original.
8. As the color correction in Step 5 affects the impact of the color burn, duplicate Extraction 2 again and move the new duplicate below the Layer moved to the top of the stack in Step 2. This helps restore the original yellow information.
9. Restore the color at the edge of the petals by duplicating Extraction 1, dragging it up in the layer stack above the levels corrected version, and apply a blend. The blend I applied was created in 2 parts. I selected Darken as the Blend Mode and then changed the Blend If settings so that the layer would darken only the lighter tones (Underlying Layer 128/166 and 255). Double click the layer in the finished example to see the Blend If settings.
There are other things you can do to improve the flower, such as some detail work on the petal edges (note the black tip on one of the petal edges to the right, for example). For these corrections you will probably not need to use the Extract function, however.
The really useful part of the Extract function, to me, is making relatively quick work of complex selection. If you are going to get in very close and do a lot of adjustment, you are making the selection manually anyhow. To get a very accurate masking with the Extract tool, you end up doing the touch up several times by repeated refinements, and sometimes it will be better to just create a single custom mask. You may end up spending less time. The short of it is, I still recommend manual selection in most cases for detailed work. In cases where the selection is obvious, it is sometimes easier and quicker to use other selection tools (e.g. the Magic Wand).
In Special Edition Using Photoshop 6, the following sections and chapters will prove helpful in clarifying more of the details discussed here.
Creating Images In Layers (53-78)
Selection and Masking (93-158)
Correction with Levels (447-456)
Color Corrections (465-484)
Combining Images: Collage and Composites (703-720)
This tutorial on the Extract function was spurred by the following reader question: <<I can't seem to get the hang of the Extract command. It keeps cutting out things I've clearly included in the outline, while adding things that are part of the background.>>