Hi Stephen,
thanks, i think the noise is due to the way the frames were grabbed, i basically found the frame i wanted from watching the rushes on quicktime on a mac, i then just used the frame grab function› (shift+cmd+4)... so the image resolution is considerably lower, perhaps only 72dpi.
The actual high resolution grab feature on board the alexa was not enabled when we filmed, which was a shame but the D.I has told me she can get full resolution frames once the footage is in F.C.P.
We recorded at pro res 4444, in Rec 709. we did this over LOG C simply due to the fact we didnt have the time to grade the LOG C footage prior to watching the rushes.
As for the ASA i tried to keep at 800asa, but there were times i pushed it to the maximum Asa, mainly out of curiosity and the conditions we were working in, I did watch some tests on a 2k projector and found that even when there was noise at the highest ASA it didnt look like video noise and had an almost silky quality to it. I actually quite liked it as it appeared more like filmic grain to me.
The lenses we used were ARRI ultra primes and a COOKE zoom. and I used only N.D filters (regular and grads)
I hope this all helps,
best wishes
kyle.