Quote Originally Posted by su_liam View Post
Can you really? Do tell. If I could work out how to do this, it would be enormously helpful. I'd give a lot to be able to edit the elevation data in 16- or, better, 32-bit grayscale and apply gradient maps and lighting effects(I wish that was a layer effect) in 8-bit RGB.
OK.

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To be clear you set the bit depth for the document as a whole. 32-bits was added recently CS3 or CS4, but the 16 bit option has been around at least for several versions before that.