R5 Mark II a sensor defect?

[Leeuw]

My R5 MkII is almost 3 months old. Some time ago I noticed this small donut shaped spot on several of my images. I do a lot of bird in flight photography and the spot is very noticeable in an even area like a blue sky. I did not pay too much attention to this assuming it will be dust on the sensor that will disappear after a good cleaning. But what did strike me just recently is that the visibility and appearance of the spot is exactly the same at full aperture like f/2.8 and a smaller aperture like f/32 implying it is not dust on the sensor. After some test shots I can conclude that the higher the iso value the more the spot becomes visible (contrast) but keeping the exact same shape. However the appearance is totally aperture independent. I have looked back to the first shots with this camera and find the spot already to be there. So it was there from the beginning and must be a sensor defect. At iso 800 it is already clearly visible and becomes worse at higher iso.

The first example is a non post-processed iso10000 jpg. See the spot a little above the upper most bird. The second example is a iso1250 jpg. Look just above the wingtip. In RAW without noise reduction it looks much severe. See also the sequence of test shots (100% crop) with increasing iso, all converted from raw without noise reduction nor contrast enhancement.

What resolution would you expect for a three months old body with this defect at delivery?

 

[Victor Engel]

It's likely a drop of oil on the sensor. Time to clean the sensor.

 

[Fred Greaves]

I would send it back to Canon along with lots of images showing the defect and let them replace the sensor since it would still be under warranty. The fact that it is showing up with different long lenses but in the exact same spot would seem to indicate it is something flawed on the sensor since dirt or dust on the sensor generally isn't visible on longer lenses.

Have you put the camera into manual cleaning mode to see if you can see anything amiss on the sensor? Remember that the image is flipped in the sensor, so if the spot is showing up at around the top third of the image, the spot on the sensor will be in the bottom third (apologies if you already knew that!)

Sorry you're experiencing this with a three month old camera!

 

[Victor Engel]

I would send it back to Canon along with lots of images showing the defect and let them replace the sensor since it would still be under warranty. The fact that it is showing up with different long lenses but in the exact same spot would seem to indicate it is something flawed on the sensor since dirt or dust on the sensor generally isn't visible on longer lenses.

Huh? Dirt on the sensor is visible no matter the lens used. The best way to make it show up is to use the smallest possible aperture. Focal length is not relevant.

Perhaps you're thinking of dirt on the lens rather than on the sensor.

 

[Leeuw]

Thanks for your suggestions. Yes, I did look today at the sensor with good light from different angles but couldn’t see any dust, dirt or oil spots. I then did a careful cleaning with a swab and optical cleaning fluid. Unfortunately the spot in the image is still exactly the same. It seems to be not on top of the sensor. It it were, one would expect a difference in appearance depending on aperture setting.

 

[Victor Engel]

Thanks for your suggestions. Yes, I did look today at the sensor with good light from different angles but couldn’t see any dust, dirt or oil spots. I then did a careful cleaning with a swab and optical cleaning fluid. Unfortunately the spot in the image is still exactly the same. It seems to be not on top of the sensor. It it were, one would expect a difference in appearance depending on aperture setting.

Yeah - did you take test shots at different apertures? What you posted was different iSO settings. If a sensor cleaning shows no change, I would agree with the previous comment, to send it to Canon for warranty repair/replacement.

 

[KevinRA]

Interesting how it shows up more at higher ISO - not seen that with dust or oil.

If on the surface of the sensor it will look very different at f/2.8, f/8, f/16, f/40 etc... If looking very similar in shape and size then must be deeper in.

 

[Laqup]

Time to check your library for images with the sun in this exact spot. (Or shots with lasers)

Just to be sure.

 

[Leeuw]

Thanks for your suggestions. Yes, I did look today at the sensor with good light from different angles but couldn’t see any dust, dirt or oil spots. I then did a careful cleaning with a swab and optical cleaning fluid. Unfortunately the spot in the image is still exactly the same. It seems to be not on top of the sensor. It it were, one would expect a difference in appearance depending on aperture setting.

Yeah - did you take test shots at different apertures? What you posted was different iSO settings. If a sensor cleaning shows no change, I would agree with the previous comment, to send it to Canon for warranty repair/replacement.

Here are two with f/2.8 and f/22, 100% crop RAW to jpeg, no noise reduction, no other processing. Yes, I’m afraid only replacement can solve it. Thanks for your help.

 

[Leeuw]

Interesting how it shows up more at higher ISO - not seen that with dust or oil.

If on the surface of the sensor it will look very different at f/2.8, f/8, f/16, f/40 etc... If looking very similar in shape and size then must be deeper in.

fully agree

 

[Leeuw]

Time to check your library for images with the sun in this exact spot. (Or shots with lasers)

Just to be sure.

Thanks, very unlikely but I’ll do that just to be sure.

 

[Leeuw]

Time to check your library for images with the sun in this exact spot. (Or shots with lasers)

Just to be sure.

Thanks, very unlikely but I’ll do that just to be sure.

Was an easy check. On the very second image made with this camera I can see the spot. It is faint because of the low iso500 but after a small contrast boost it is clearly visible.
One lesson learned: at the arrival of a new camera always check the sensor for spots by taking a few picures out of focus with 1) high iso and 2) small aperture

 

[Laqup]

Time to check your library for images with the sun in this exact spot. (Or shots with lasers)

Just to be sure.

Thanks, very unlikely but I’ll do that just to be sure.

Was an easy check. On the very second image made with this camera I can see the spot. It is faint because of the low iso500 but after a small contrast boost it is clearly visible.
One lesson learned: at the arrival of a new camera always check the sensor for spots by taking a few picures out of focus with 1) high iso and 2) small aperture

That's unfortunate. Make sure to do a full "SW sensor clean" as well from the menu. Sometimes this is mapping out / correcting slight sensor defects by "calibrating" individual pixels and / or replacing dead pixels with average values of the neighboring ones.