Did a quick check, to check for noise patterns with long time exposure at decent ISO levels - just to see and understand the pattern.
I did a 30 second exposure at room temperature, no lens on the camera, cap instead, viewfinder closed where possible, dark room.
ISO set to 12.800. 3 cameras: D5, D4, D750
Basically all 3 camera have very low noise levels, potentially not seriously impacting in these condition image quality. Basically 3x dark frames with very low noise levels.
Just for visualization: Raised exposure compensation by + 3 EV with NX-D, NR=off, saved file to 1200x800, high quality
If someone is interested in downloading the NEFs <
click here>
Interesting to see the patterns. My interpretation:
1) The D4 has "balanced" red and blue chroma noise, amp glow on the left side of the recorded frame. Some horizontal banding.
2) The D5 has a rather red dominated chroma noise, blue noise is lower. The amp glow is on the right side of the frame
3) The D750 has the lowest noise level at this setting. Amp glow is on the bottom of the frame. Some horizontal banding.
(I did longer exposures as well, where the amp glow was much "better" visible)
rgds, Andy
1) D4, 2) D5, 3) D750