Post Processing - or before the final scan?

[FrostMoose]

I understood the general consensus is that it's best to do the majority of image processing after scanning with a photo editor? - but today I found this "The basic idea is this: you can scan with default settings and make big adjustments in P'shop or GIMP. But those edits are destructive to the image. They basically take the information already inside the image and stretch and squeeze it, throwing away detail. When you make adjustments to a histogram before you scan, you begin with a full value range without any tones that have been tossed out by a graphics program" - ~ I like this idea, but how true is it?

[LSI_Ketelhohn]

Dear customer,

The scanner's color space is much larger than any normal color workspace.
Therefor all adjustments in SilverFast are done before the colorspace transformation.
The most important setting are the highlights and shadows, because they define the true color range of the image. This "cuts off" the empty area behind and in front of the historam and makes sure that only the image data is stored in the final color workspace.
If you do not do this in SilverFast you WILL lose image data information and dynamic range.
This can not be compensated in a later image editing software.
You can either set the highlights and shadows automatically using the auto adjustment (e.g. Auto CCR) or manually using the Pipette or histogram.

Kind regards,
Arne Ketelhohn.