Nikon Compressed RAW & Nikon Capture question

[Franglais]

OK. I bought Claude Tauleigne's book on the D200 (sorry - it's in French). This is the first of a series of questions prompted by things in the book.

Claude says that uncompressed RAW has 4096 values per colour per pixel whereas compressed RAW has only 683 values per colour per pixel. This is hardly destructive because the number of values the human eye can perceive is less.

Yes but what about when I use the Exposure Ajustment feature of Nikon Capture Advanced RAW features? Where is getting all that extra detail from? By starting from a compressed signal am I losing something? Does anyone know how it actually works?

Anyway - I've turned off the RAW compression feature on my D200. I have a 4GB card in it and I have space for 223 images.

In attachment - a couple of pictures from the torchlight parade in the village last night. I was doing auto-everything (including auto ISO) and out of 46 images I just had to correct three images like this one where the D200 accorded too much importance to the torches. I just adjusted the exposure by +1.75 stops.

Charles