I love adjustment layers.
They are so easy to use, edit and correct
and you dont loose quality in your original
image as you are working with a separate
layer for your adjustment.. Chineese?

There are three things which you need to keep in mind.
1- The adjustment layers are found either in the top bar
layer tab: new adjustment layer, or the layer window tab
as used here. The black and white circle refers to the
adjustment layer. Just click on it and a selection of
adjustments will become visible.

2- Here I have used the Hue/Saturation and reduced the
saturation to reveal a completely B/W image. To edit
this selectively you can use the paint brush (4th tool
down on the right of the tool bar) with the background/
foreground colour. I circled it in red for ease of
reference. In this case the background is white:
this will reflect your adjustment. When you paint in
with black (by ensuring that the foreground is black-
black square on top of white one by clicking on the
little arrow to the right of it) the adjustment is erased.
You can repaint the adjustment by changing the back/
foreground again to white and painting in with white.

3- This is a rough indication of what you can do and
B/W is the easiest tool to display the effects. You can
also do this with any other adjustment. If you want the
face to be in black and white and the rest in colour, just
fill the H/S layer with black and paint in with white.
The adjustment will only appear where you paint in.
At the end of the editing process, you can flatten the
layers or save the file as a PSD so that you can re-adjust
the changes whenever you re-open the file.

Pure flexibility and probably the best tool in Photoshop.



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