I have footage from a 5Dmk2 that I've transcoded to ProRes 422 in both Compressor and MB Grinder and they look different.
The conversion from Grinder looks slightly crushed in the blacks and mids and slightly lifted in the whites. The saturation is increased and it also looks a bit softer. There's a very noticeable difference when looking at the waveform monitors.
Don't know if anyone else has noticed this, but couldn't find any posts on it?
Odd. I recall doing testing comparing the two for a review of Grinder on my blog, and I didn't notice any difference. The clips were identical. Well, I was running (am still) Leopard, not SNOW Leopard. What OS are you using? Are you judging in FCP, or QT?
I placed the clips on different layers on the same timeline, lined them up and toggled between them.
V1 - original clip from 5D;
V2 - Compressor clip;
V3 - Grinder clip.
The difference between the Compressor clip and the original clip is very slight and barely noticeable by eye, although there is a difference on the scopes. Whereas the difference between the Grinder clip and the original is marked and clearly visible by eye.
Also, the Compressor clip seems sharper than both the original and the Grinder clips - very strange.