Thanks David. I know "noisy" is a subjective statement, I guess I was expecting a cleaner image from the Alexa at 800 ISO. I also have to admit it was shortsighted from my side not to do a comparative test between Log C and Rec 709. Tomorrow morning I will run the same test on the same camera, this time on Log C. Testing another camera might not be an option since our rental house has only one body. Today at the post house I brought up the possibility that the monitor was causing the noise, but the colorist rejected that idea. I will insist tomorrow on see the test on more than one monitor.
Thanks again,
Demian