In low lighting conditions I have to bring up my ISO (even when using flash) and open the aperture to a certain point to get the ambient light alongside subjects I'm photographing (which are mostly lit by bounced flash).
Just this weekend I was working with Canon 5D mk3 mostly in Aperture Priority mode (somewhere around F/7.1 with ISO5000), and I notice that some of my photographs have practically negligible amount of noise, while other had really noticeable amount of noise, which was not that big of a problem, but I was wondering:
- What would be a factor that "reduced" noise in some shots, because the only two variables would be the shutter speed, and the amount of light in the room?
- Does shutter speed somehow affects noise?
- Does the amount of light affects noise?
- Are there any other factors that would prevent or reduce noise at the moment of taking the photograph?
P.S. I'm sure you got it that I'm not talking about post-processing, but here's just another mention for those who don't.