I would like to ask for your opinion whether in your past experience you have seen similar kind of red noise in lower parts of your pictures in low-light settings?
It shows up in lower edge and corners. It comes out when this part of the composition is mostly black or dark and there is a low-light setting where I need to slightly increase the ISO.
At first I thought I went too high with the ISO (on previous pics I have noticed this, the ISO was sometimes 1600) but this sample picture was shot at ISO 640, 18mm, f/3.5, 1/60 sec on a Nikon D5600 with 18-55mm kit lens.
I added a new picture that I have processed in which I noticed unusual noise around lower/right edge. Picture parameters: ISO 1000, 18mm, f/3.5, 1/20 sec.
Of course I understand that normally one wouldn't push the exposure up so much, to create so much noise, but just for illustrating my noise issue I did it anyway... :) The right side looks like it is burned out from the very edge, whereas all other areas seem to have "normal/regular" noise.
/edit2: I have been in touch with Nikon and there has been some back and forth but the customer service agent seems to be reluctant to acknowledge that this could be a sensor issue, even though I proved that it could not be the lense by exchanging my 18-55m kit lens for a fixed 35mm prime lense and seeing the same results:
Questions: Does anyone have any past experience with Nikon Customer Support? Is it unrealistic to expect that they will admit that it's likely an issue with the sensor? Also, is there any chance they will opt for replacing my camera body or would it be necessary for me to send it in for examining and possibly trying to repair? I have no past experience in this so I'm not sure what to expect. Any advice would be greatly appreciated!