Large Rings or Circles in previews. 5D3

Hello Everyone,

I was shooting yesterday with my 5D3 and Sigma 85mm f1.4. Towards the end of the shoot I noticed concentric rings or circles in the previews in back of the camera. The images below is what I see in back of the camera's LCD window.

The rings/circles also show in Mac Lightroom's import window but once the images were imported into Lightroom the rings/circles were gone.

Media Pro's show the rings/circles with both thumbnail and full image preview.

Interestingly previewing in the latest Bridge the rings/circles would show briefly as the thumbnails were built. But once built the circles/rings were gone.

Using the Canon DDP 4 software there were no circles/rings at any time.

I shot over 500 images and the circles/rings didn't appear until the end of the day on about twelve images.

Thanks for your help!

Bizarre - they are obviously in the embedded jpeg that is used by MediaPro, the import windows etc. However, Lightroom and bridge will use that while they do their own raw conversion from the .cr2 and then use that for the future. The processed raws don't show it, so it's related to the in camera jpeg processing. No clue as to what might be happening there

Very strange ... never seen or heard about those ring ...
Look like it start on the first over exposed picture, perhaps start the search around there, like what did you do exactly just before to take that first "ringed" picture ?

Like said before, it's in the preview thumbnail, DPP ignore it, LR see it but built it's own after few seconds, your camera show it ...
Hum ... very curious ... is the CF/SD card faulty instead of the camera ?
May be a CF/SD card format can solve it ? ( just some suggestion )
Did you try with another CF/SD card ?

Thanks guys. I was using both CF/SD card slots in duplicate/backup mode. Files on both cards matched each other.

Yeah I'm not sure why I over exposed those frames. I think I was adjusting the f-stop to shoot wide-open and didn't compensate for the shutter speed. Only been shooting for 35+ years... I'll get it right some day!

Tomorrow morning I'm gonna take a ride to the Canon Service Center here in New Jersey. The camera is a month out of warranty. Hopefully they won't charge me for the repair.

I do agree it's only in the embedded jpeg preview... luckily.

Thanks again.

Update!

Just got back from the Canon Service Center here in New Jersey and they couldn't reproduce the effect with either my Canon 50mm 1.4 or their Canon lenses. They suspect it's my Sigma 85mm that's causing the issue by sending some kind of bad info/signal to the camera. I kinda agree also. In retrospect I should have given them the Sigma lens to test.

The Sigma stays on my 5D3 95% of the time and it's been months since I removed it. It's a wild guess but maybe just the contacts needed to be cleaned. I'll do some testing of my own.

Even though my camera was 1 month out of warranty they still covered it with free warranty service that included cleaning/adjusting and attached was my Canon 50mm 1.4 that's over twelve years old, they cleaned and calibrated it for free. Gotta love Canon!

It looks like "Lens Aberration Correction" algorithm gone bad, maybe a dodgy firmware.
Try disabling that option in the camera.

adas wrote in post #17082830
It looks like "Lens Aberration Correction" algorithm gone bad, maybe a dodgy firmware.
Try disabling that option in the camera.

Oh Yes ! not a bad idea / path to search !
i will add, may be the camera try vignetting/light fall off correction, "thinking" it's a Canon lens ...

Well it wasn't until a few months ago that I found the culprit. The setting Peripheral Illumination Correction (PIC) was ON and causing the problem with the Sigma 85mm. I sent the lens back to Sigma in Long Island and they updated the firmware. All is well now but I keep PIC off just in case.