Just wondering how some extracted and shape from an image. Meaning from the example image I provided, I would like to make the “minute man” a solid colour, I was always taught to use the wand tool or the pen, but I remember reading a while back that you can change modes to extract the shape. Do most use the extract filter?
actually, i typically don’t apply them method i mentioned above. rather, i usually drop that onto a lower layer in illustrator, freehand, fireworks, just some vector based program so that i can trace over it. works nicely for when you have to resize.
you mentioned at the start you thought about using blending modes - that can kinda work, especially if it’s just for quick stuff.
if you can get your image background to white (instead of yellowish) then you can set the mode to “multiply” and whatever is underneath will show through. Note that you aren’t actually getting rid of the background (so for example if you wanted a clean b/g for use on a website you’d need to go in and actually delete stuff) but for things like colorising a sketch you’ve done, you can put your new layers UNDER the line art layer which is set to multiply, works fine.
in regards to using channels as masks, check this tutorial…
incidentally, to save everyone time you could have gone to google, searched for “channel mask” and clicked on the FIRST entry that came up…