Canon 5D Mark IV: Is this normal?

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I just purchased a 5dM4, and think I am observing a peculiar issue with banding in exposure times over about 6/10's of a second or more.

A prominent horizontal banding displays that can not be seen on shorter exposures, like 1/30th of a second.

To most easily visualize this, I took two dark frames, one at 1/30 and one at 1 second. In Lightroom the only alteration is set the white point clipping to the same value for both exposures and turning off NR & sharpening for both exposures.

Is any one else seeing this horizontal banding? I am not expecting perfect shadows, but this is surfacing on exposures around a second and greater, and not on short exposures.

This problem notwithstanding this "brickwall test" is showing up in more normal edits too, places where my 5dM2, with its not so great shadows seems to be better than this issue, as this banding appears to be large streaks of chroma.

I tested this out dark frame scenario on my older 5dM2, and the results while different, are not this dramatic.

Note I resized these to 1024px wide to keep within the file size attachment restriction.

[Rado]

There's a long thread about this over at canon rumors forums

http://www.canonrumors.com/forum/index.php?topic=31076.0

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Thanks Rado for the link, not sure these are the same issue (they might be) but quickly viewing the examples they posted these are for rather quick exposure times. In my case, I am noticing a discrepancy in image quality between short exposures and longer exposures that show off a marked degree more banding.

[Bart_van_der_Wolf]

I just purchased a 5dM4, and think I am observing a peculiar issue with banding in exposure times over about 6/10's of a second or more.

A prominent horizontal banding displays that can not be seen on shorter exposures, like 1/30th of a second.

To most easily visualize this, I took two dark frames, one at 1/30 and one at 1 second. In Lightroom the only alteration is set the white point clipping to the same value for both exposures and turning off NR & sharpening for both exposures.

Hi,

Well, a black frame should be black, so did you brighten the result (Exposure/Levels/Curves)? Have you tried converting with another Raw converter, e.g. Canon's DPP (without noise reduction), or RawTherapee? I suspect that Lightroom plays a role in this (e.g. how it handles the Blackpoint), but it would need to be compared with something else to make sure. Canon should know how to optimally convert the Raws, so I'd use that (Digital Photo Pro, DPP) as a benchmark.

Is any one else seeing this horizontal banding? I am not expecting perfect shadows, but this is surfacing on exposures around a second and greater, and not on short exposures.

The effect on slightly longer exposures (don't know where the automatic NR kicks in on the 5D4, maybe >2sec.), with long exposure noise reduction enabled, should look different if the phenomenon is Random. If the amplification differences are not random but systematic, it should look similar.

Cheers,
Bart

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Hi Bart, the white point was increased, this is to show the effect I am seeing. The large bands of green crop up during basic shadow lifting, only on long exposures (around a second or more), NOT short exposures of say 1/30th. This happens irrespective of the scene. I understand the frames should be black, but by changing the white point on the dark frame I can more easily show the issue to you. My lightroom workflow on the 5DmarkIV is the same for my 5DMark2 images, though the 5DmarkIV appears to exhibit a horizontal chroma banding.

[Chris_Brown]

Try a test using DPP for raw file processing.

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Spoke with Canon technical support who indicated I should not be seeing this type of behavior and suggested I just return to vendor.