Here's a weird one!
Greetings from Finland! We had some lovely aurora last night, but you can imagine what choice words I was uttered when I looked at my pics on the laptop this morning .. all of them have these strange concentric rings in the centre. Anyone else ever had this? I've googled but nothing conclusive .. some say it's reflection from the UV filter (I don't think so - I've always used one and never had an issue) .. some say update the firmware (already done) .. really frustrating! Hoping for another dose of the green stuff so I can try another lens, just in case it's the camera :-(. Canon 5D Mk4 here ..
Great to know you've got those lights around! Make the most of them.
I've read that ANY piece of extra glass between your lens and the borealis will cause these rings. All to do with reflected light. Which leads to the question: why have a UV filter for this? Appreciate you've said it's not happened before but in this case, take the filter off and see the results.
Long ago, I bought the UV and skylight filters for the lenses I then had. I then read so many articles that make it clear that the less you have between your lens and your subject, the better. What do these actually do? Yes, grad and ND filters plus the always great polarising filter are all great when needed. Otherwise, why potentially risk your work with an unecessary piece of glass? Good luck and take off your UV 😁
The artifacts look a bit like a diffraction optics grating. You're not using a DO lens are you?
It reminds me a bit of experiments we did at school in the physics lab. Laser light (and perhaps aurora light) has such a uniform wavelength that it will diffract and refract into patterns like this. PS You're still sticking with Canon then!?
... which is probably what BC and DD are saying.