XnView Software

Thanks for confirming.
I guess I need to wait for libraw to add support for Nikon HE/HE* RAW, or shoot in 'standard RAW'

Sorry - here's another:

https://we.tl/t-ZmIXJ3s7al

Yes I left that setting turned off (the default)

Yes, set to default. But the same happens even if I convert to JPG.

I think the issue is with reading the file, not converting it.

I'm not sure libraw supports Nikon HE/HE* RAW format (which is what these are saved as). This might explain why it doesn't work for me, but not why it does work for someone else ...

That's very weird .. it doesn't do it for me, I just get the rainbow output. Just tried with another file from the camera.
I get the same corrupt-looking file if I try and convert to another format such as jpg.

If I try and convert raw files from my Sony camera, it works just fine.

Does it use ...

I have some RAW (.NEF) files from a Nikon Z6iii which I'm trying to convert to TIFF.

When converted the TIFF files seem corrupt:
I've uploaded one of the NEF files in case you needed to test: https://file.io/Rm4dpVEAHwcS

Thanks