Vertical Banding?

[David Chapman]

I've read from some other forums about major problems with vertical banding. I took some sample stills from test footage earlier in the week to see what you guys think. Do I have a vertical banding problem?

I saw some noticeable banding in the orange/brown wall. I didn't see as much in faces, but then again, it might be there.

Here is a link to my sample stills. Just click to enlarge.

7D Test Footage

[Daniel Browning]

Originally Posted by James Chapman

I've read from some other forums about major problems with vertical banding. I took some sample stills from test footage earlier in the week to see what you guys think. Do I have a vertical banding problem?

Yes, you certainly do. I see strong vertical lines. The 7D has four different "banding" problems:

• Fixed pattern noise.
• Variable pattern noise (vertical lines).
• Offset and gain imbalance between green channels.
• Posterization.

My guess is that your problem is one of the first two. If so, then it would go away at ISO 800 (HTP disabled), as the amplified signal will be too strong to get a contribution from the pattern-noise contributers (whether amplifiers, ADC, or something else). If it doesn't go away at ISO 800, then it's the offset/gain imbalance problem, and some cameras don't have that issue, so you might get lucky.

[David Chapman]

I'll do the test again at ISO 800 and repost some photos. I read on another forum that Canon gave a guy a new 7D and the vertical banding was resolved. He had determined that it was a calibration offset dealing with the HTP. If that's the case, maybe I should contact Canon or return to Best Buy?

[Daniel Browning]

Originally Posted by James Chapman

I read on another forum that Canon gave a guy a new 7D and the vertical banding was resolved. He had determined that it was a calibration offset dealing with the HTP. If that's the case, maybe I should contact Canon or return to Best Buy?

Returning it to Canon would be great if that fixes it.

[David Chapman]

Here is a quick sample with HTP on and off.

I saw a test with the noise patterns and conducted one myself also. ISO 160, 320, 640, 1250 were the best to shoot video with. Here is the link:
Canon 7D ISO versus noise test images Marvelsfilm’s Blog

Tell me if you see any vertical banding anymore. I performed the 1.0.9 update and it might have gone away???
I was thinking the banding might have been caused by my Extreme III cards at 30MB/s, but I don't see how 45MB/s on Extreme IV will add anything if the rate is only 45Mb/s. But that's another topic already present.

[Benjamin Eckstein]

James,
I am finding it hard to see if there is banding with either of the 2 images you just posted. In fact the first pics you posted I could just barely see it. Maybe I am not looking at the right thing. But FWIW, what I did see on the first pics I see on my cam too, but I have only had a few days with the camera and assumed that was just part of the codec.

Haven't done the firmware upgrade yet.

But with the 2 you just posted I am staring and see nothing. Which leads me to believe if there is a problem it only comes up in motion or don't worry about it.

[Daniel Browning]

Originally Posted by James Chapman

Tell me if you see any vertical banding anymore. I performed the 1.0.9 update and it might have gone away???

I don't see any banding in either of those two images at all. I don't think the firmware update is supposed to address it. There may have been another difference that affected it, such as color balance of the light and/or white balance setting. (For example, banding is much more apparent in tungsten.)

Originally Posted by James Chapman

I was thinking the banding might have been caused by my Extreme III cards at 30MB/s, but I don't see how 45MB/s on Extreme IV will add anything if the rate is only 45Mb/s. But that's another topic already present.

I don't think that's it.

[Benjamin Eckstein]

I see banding slightly on my cam. Took it to the store and tried 2 other bodies at the same settings and dumped the footage into my laptop and seemed to see the same thing. So I kept my body (even though they offered an exchange). I felt like sort of a jerk trying to stare and point at these images to the salesman (who was quite knowledgeable...this was a real camera store) and show him what I was seeing, which seemed quite slight. It made me realize that if you have to stare that hard that it's probably not an issue.

So yes, maybe some cams don't have the problem but the 3 I tried do and I can see it (now that I am looking for it) on a lot of the Vimeo examples which leads me to believe it's on many more cams (at least at certain settings).

So I am just going to ignore it, because I can guarantee that 99 percent of the people watching this stuff won't be looking for it or see it. Sure it's not a perfect image, but we bought the cams knowing this.

B

[David Chapman]

Since I never owned the 5D Mark II, I started looking into the responses from that camera early on. There is an updated firmware that resolved the vertical banding in video mode on the 5DM2, but before it was available, Canon apologized and instructed to turn off Highlight Tone Priority until the issue was resolved. I've kept this off when shooting video and it seems fine.