Although I had been using scanners for years, I did not really realize that you can set a scanner's "exposure" much the same way as a camera's. So, even if you have software (such as Vuescan) that can produce a "raw" scan, it's still crucial to get the exposure right the first time.
How do you go about setting the optimal exposure on a scanner? The one I am using is Nikon Coolscan 5000. In Vuescan, the value starts at "1" and goes up.
My guess is that the tradeoffs are (i) noise generated by inreasing the exposure vs. the noise generated by cranking up the shadows in Photoshop and (ii) of course the highlights vs. the shadows, since I am quite surprised that even slides have more exposure latitude than a scanner.
So when scanning, do you expose for the shadows and let the highlights go, or do you expose for the highlights and then bring up the shadows in Photoshop? And what does "exposing for the shadows" mean in this context--how do you know when you've exposed for any thing?
I hope my question is at least somewhat lucid, or am I completely off the scent here?