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Weird 5D artefacts


Well-Known Member
I hope someone can explain me what the heck is this about. This tourist shot was made by new Canon 5D camera with C/Y Distagon 2.8/21 attached (Fotodiox adapter):

I didn't do any processing in Photoshop. This is ISO 1600, so it's noisy. Anyway, center looks like it's supposed to look:

Now look at the corner:

I suspect that this is because of narrow angle of light coming to sensor's surface. Well, may be I should have my RTS III while travelling next time. Any othe thoughts?


Well-Known Member
At first sight I would have thought that those strange highlights were street lights affected by camera movement but the rest of the picture doesn't seem to suffer from that, so I don't know... strange.


Well-Known Member
Sergei, You're probably right in your explanation. Wide angles behave strangely in the corners with FF digital sensors. The highlights seem to be causing some sensor blooming which in this case looks like a star effect. Nothing to worry about if you ask me, the effect isn't ugly and even adds something to the photo.


Well-Known Member
No, this is straight CR2 file taken to Photoshop as is. Here is another corner:

Interesting that only bright light sources produce those "stars". Smaller ones look OK. Yes, this is most probably the result of light diffusion on sensor surface.


Well-Known Member
No, it's not. Take a look to the center. Camera movement would produce uniform shifts across the frame. I didn't have a tripod, but I managed to "fix" the camera in the grid surrounding this vista point on top of the "Eifel Tower".


Active Member
It depends on how you shake the camera...What I see it's kind of like a food tray effect. The stuff in the center shakes a lot less than the stuff on the corners of the tray. Take a similar shot at the same ISO with a tripod next time and I bet it would not be there....


Well-Known Member
Hi Sergei,

I agree that it is nothing to do with camera shake as the buildings and cars around those lights are pin sharp. It appears that the three pointed stars are only where the light source is white, as the blue and red lights do not seem to suffer to anywhere near the same degree. Could you email me the full size shot of the first picture for me to look at and drool over?
It would have been great to see a low iso shot of the same, as the 1600 one is quite something. That 21mm Distagon is something else!




Well-Known Member
It could be movement, I also thing it is mostly corner problem. But you are using the best combo already for this extreme situation. your RTS III could have better corner resolution, but the nothing beat 5D in hi ISO today.

Just imagine you shot this with Canon 16-35L, you would not be able to see any cars in the corner at f/2.8