Why different results?

[JayC]

I have been using ACDsee for many years and am on the current version. I also have Photoshop cs5. I use acdsee for most of my edits and cataloging. I just bought a Canon 1ds Mark II because I want to sell my Nikon d3 for some extra $ in the bank.
I have been testing the camera constantly and am appalled by the noise even at low iso. On a whim I decided to process the same file in cs5 and acdsee. What was apparent the instant I opened the files and before working on them, is that the noise was there when viewing the file in acdsee, but when viewed in cs5, the noise was substantially less.....
I did my edits (no noise reduction) and opened each file in each software. The cs5 one still has way less noise. I was ready to give up on the 1ds, but this begs the question.....
What gives?

[Manuphoto]

Adobe CS5 uses Camera Raw, that might have a better RAW processing than ACDSee. What version of it are you using?

It's not abnormal to observe that. For example, Aperture 3 handles noise better than Aperture 2 did, all my high ISO shots with my old Nikon D50 just got better in 2010