rick.lang wrote:The false colours are perhaps more reliable to judge an image in the shadows than using the histogram. The ‘native’ ISO is 400 and best to use that value as Jamie mentioned, controlling light to ensure there’s no purple except where you expect to be near black for your deliverables. Nothing wrong with black, but keep the shadows dark grey or just turning blue when you want details to be visible in your grade.
The histogram will certainly show you black but you don’t know where in the frame that’s happening. False Colour will tell you what and where it is unlit and you determine if that’s okay or not.
Did some more testing with your instructions in mind and am now understanding the results. Exposed a scene with areas from red to purple last night. As the exposure progressed into the blue areas noise increased as per your observations. Going into dark blue and progressing into purple the noise and "flashing" (no idea what the proper term is) manifested as edge movement, i.e. the edge of a dark couch appeared to be moving and morphing against a much brighter wall background. Moving up the scale, grays started to be more acceptable with some noise reduction (25%) in Resolve.
It will be challenging for me to understand how to manipulate the blue/purple areas to achieve some of the wonderful low light footage I have seen where fire light is illuminating a subject. Obviously black is used along with grey and up and the troublesome blue/purple has been omitted/bypassed?
Amazing hobby! Plenty of meat here to work with. This should keep me busy for a good long time.