I just purchased a Sony FS700 and Atomos Shogun to capture 4K raw. I had a shoot recently that was at night with some backlight and edge lighting around an actor. Was shooting 4K raw at 24fps, shutter was 48, aperture 3.5, ISO 500. It looked really good on the Atomos monitor, but when I imported the footage it had so much noise/grain...it is completely unusable. This has been a recurring theme with this camera thus far. I am getting grain in pretty much everything at ISO 500. The other settings have varied...have tried HD shooting at various apertures etc...but unless it's an outdoor shoot with plenty of sun - there is grain in everything at ISO 500.
Is there something I'm doing wrong? I'm having trouble figuring out why everything would have grain, and I can't seem to be able to find any info (it seems like I'm the only person in the world having this problem)