EOS R6 Strange spider web like artifacts on long exposure shot

[frijsdijk]

This shot was taken with the R6 and the Sigma Art 35mm DG HSM (with the Canon EF/RF adapter). Observe the light reflections from the car on the grass 1:1 pixel. It's like there are spider webs there, but there were none and certainly not shaped like this. What are we looking at here? Looks like some sort of artefacts to me.

Edit: Google Drive Link: 

https://drive.google.com/file/d/1HIZLeD3MUJ_yBOouzYte9jDNxflON8iJ/view?usp=sharing

[frijsdijk]

Ok this didn't really get me anywhere, dissapointing.

[Waddizzle]

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@frijsdijk wrote:

Ok this didn't really get me anywhere, dissapointing.

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The image John posted doesn’t look like it began life as a single photograph.  Is it a composite of several images together, creating an ultra wide view?

If so, then the stitching process could have introduced artifacts in the end result.  I often shoot pano shots, and have had artifacts introduced in a few of my shots.  It happens most often on night shots or when the samples do not overlap sufficiently.

[frijsdijk]

Is that even a serious question? I mean, if I had stitched images together and get artefacts like that, I would come to a Canon forum asking for an explanation?

I even attached a RAW file. How do you even stitch RAW files together INTO a RAW file??

[Waddizzle]

Yes, it’s a serious question.  The image seems to have a nonstandard aspect ratio.  No, I have not downloaded your and don’t plan to. I can create composite RAW files in Photoshop.