Jani, did you shoot RAW? put that RAW file through ACR with 'reduce colour noise' set to just '10' and all that nasty colour noise will go, disappear completely leaving some luminance noise looking rather like NPZ....
Yes, I shot it in raw (as always), but as mentioned, I performed no noise reduction to help show what one has to work with (without posting the raw file, which of course is huge).
If you're thinking about the red blotches on the carpet, that won't go away completely, because it's actually a material similar to velvet, and the carpet isn't completely flat even though it's vertical.
The noise in the faces can be reduced to insignificance around 35/25 luminance smoothing/color NR, but it
removes detail (most notably from the hair). The detail in the carpet is irrelevant IMO, so a selective NR would be preferable. But I'd rather do a test print first to see how much noise and detail survives that process.
One thing that I will say though with the 5D, the AF is not fast even with an f2.8 lens (really slow with an f4 which is one of the reasons why my 24-105L lasted only 3 weeks!) in low light.
The 20D is no racer, either. The 5D beats it in precision and servo focus when you're using the center. But the 1D MkII crushes the 20D, it can get focus in circumstances when the 20D simply refuses.
With EV6 or so the speed is the same whether using the flash assist or not and it isn't very fast, but Canon's flash assist AF system is so slooooow compared to the equivelent Nikon system with real world shooting in low light, especially with moving subjects. When shooting a wedding you often are focusing, recomposing (the off center AF points are glacier slow in low light and hunt a LOT)
That figures; the center point is assisted by extra invisible points on the 5D, while the others are just like on the 20D.
It's one of the compromises which I find unacceptable in the 5D at its price point.
Since focus-recompose is inherently bad when DoF is shallow, that makes it even worse for you and me.
and shooting to capture those magical moments; the amount of times that I'm frantically pushing the shutter release through to the floor for what seems like eons (i.e. a full second) as the camera slowly focuses then shoots, and that is with center point and a USM f2.8 lens.
Which f/2.8 lens is that? The 70-200 IS doesn't feel slow, even on the 20D, but it's slightly quicker of course on the 1D MkII. The 24-70 exhibits similar speed improvement, but is inherently slower than the 70-200 for AF.
Try borrowing the 1D MkII (N) and see what you think of it, even though it's as heavy as the 1Ds MkII.
I'm holding off any new body purchase until Canon has finished delivering (or not) on the rumours this fall. And I've resisted the temptation of purchasing a used 200mm f/1.8L, even though the price was right. D***, I'm good.
If the D2X was less noisy and less diffraction limited, wow is the low light AF on that thing fast!
I'd love to try that low light AF. Or maybe not.
That said....your medium format shooter isn't going to be shooting anywhere near that fast is he?
That's my thought, too, unless he wants to change his style.