[Edge]

Im working on my first piece in photoshop. The thing is, my drawing was scanned. I created a copy of that layer and set it to multiply so I could pait over my drawing, but had the original in the background layer to use as a guide line. Now I know I mustve screwed this up becuase I dont know how to get the white on the multiply layer to become transparent so I can paint another layer below it as the background. Did I screw this all up?

[hamilton]

make only your sketch layer visible.
open the channels tab. (probably next to layers)
click the left-most button on the bottom that looks like a dot outlined circle.
this selects all the whitespace.
go to the selections pulldown and invert the selection, so that the blacks are selected.
go to the layers tab and create a new layer.
use the paintbucket to fill, or make black your backgroundcolor and click ctrl+backspace, maybe apple+backspace on a mac, i dunno.
now you should have a transparent layer with your pencils on it.
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[cheney]

I am going to assume your sketch is a dark grey or black on a white sheet of paper. Duplicate this layer as you did, and set the new layer to darken. The more white the background of this layer is the more it will be transparent, and the opposite is true for dark tones. You can perfect this by manipulating the layer's contrast, desaturation, and highlight tones.

The other solution is to paste the image into a new channel. This will yield vastly more accurate results, but it also requires a bit more editing.
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