Thanks for that Luca it makes perfect sense.
Just checked in the manual for the Canon 40D and RAW is 14 bit.
All my editing is done in 8 bit so I guess I'm losing quality, which I assume now is colour related. My train of thought was if I could edit in 16 bit then maybe the loss quality wouldn't be as great.
Last night I took two shots of the same landscape one with the normal camera sharpness and the other set to maximum, I couldn't see a difference between then when viewed at 100%.
From time to time I float around on POTN and see some pin sharp images and I'm trying to work my way towards those sort of results, I understand that the lens will probabley play a big part in that quality.
Thanks for the info
If you want to edit any of my images to demonstrate points/techniques to either myself or others please feel free to do so.
Still learning with Canon 40D, 28-135mm, 100-400mm L and Elements 6.
Any Advice greatfully received.