Ok so I skimmed through the conversation here, but as an owner of both Nikon and Canon cameras, I do understand.
As long as you're using all manual settings on your Nikon (and I mean going through every single setting the camera possibly has and making sure it's all manual and all the auto things are off), then it's unlikely to be the camera. However, it could be, like Smeagol said, it's possible that its the shutter.
However, that's generally not the case, so I would say it's the lenses. You say you're using Nikkor lenses. Sure, they're primes and all, but they're still Nikons. All Nikon lenses (manual and automatic) have a little spring tab on the back that causes the aperture to spring all the way open by default when on the camera.
Here's a picture of the little spring:
Here's a picture of how the aperture opens all the way on the camera:
Whenever you press the shutter release button, it not only takes the picture with the shutter, but also drops the aperture down to your preset aperture at the same time. Then it pops it back to full open so you have a bright picture through the viewfinder. The issue here is that it doesn't do it to the same place every time.
To fix this (as far as I know) on a Nikon camera (using a manual lens), you have to just not put the lens on all the way so that camera doesn't spring the lens aperture.
So even with manual lenses on a Nikon camera, there can still be some issues with the aperture springing all the way back.
I know that when I got my first manual lens (not a Nikkor lens), the light flicker ceased all together in my videos because I had done everything else right with the lighting, clothing, reflections, and camera. But then I switched to Canon because I wanted to have some more flexibility with software (since the D3100 is super limited and not a great camera).
If you do decide to get a Canon, I can recommend the SL1 because of its size and because it's the only one I own. Like Smeagol said, any Canon is really fine as long as it works with the software. You may want to consider one with a flip out screen and a mic jack, though, if you plan on using it for video as well (I didn't think I would want to when I bought my DSLR but now I kinda want to haha).
I hope you solve this issue!
Edit: I made a video version if anyone's interested in sharing this to other Nikon users in need.
https://www.youtube.com/watch?v=QPOmHyL9Wtg
Last edited by rioforce (May 13, 2017 (06:44pm))
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