I am floundering trying to edit RAW files in Photoshop CS.  My current
issue/question is the correct setting of the exposure control.  Should
I set the control so that the photo looks to be correctly exposed in
the preview screen, or should I set it so that none of the color
channels are being clipped (at least significantly clipped)?  If I do
the latter I can end up with some mighty dark images, which normally
require more significant editing later in PS. If I do the former, then
one or more colors can be clipped.  The clipping is apparent if I open
Layers later during editing, but not necessarily in viewing the image.

Adobe Photoshop CS HELP suggests that holding down the ALT key
(Windows) or OPTION key (MAC), slide the EXPOSURE control until some
clipping is evident, and then back off a bit.  Do the same for the
SHADOWS control at the other end.

Help/suggestions are requested and will be appreciated.