HV20 flaw... Digital Ripple - Rolling Shutter problem? in the Vimeo Cameras Forum

Mutcluck 4 months ago

as anyone had problems with the HV20 having digital ripples run through the footage? That was a big problem for me with my John Muir Trail footage. It kept popping up in the editing process and I had to edit around the worst ruined footage.

I keep thinking I see it in other people's work too, but no one else seems to notice or say anything. Am I crazy, because my HV20 was stolen in Africa and I don't think I'm going to buy a new one for this reason alone. Maybe I had a faulty one, but I'm worried its an artifact from the rolling shutter, which even scares me off of the spendy new Sony XDCAM EX1 and the Red Camera (can't afford that though) Am I offbase with my worries or are they valid? If this is a potential artifact on all camera's with rolling shutters, I won't buy another one.

This is the best example of what I was seeing in my footage. Ignore the person's DOF adaptor and the fact that it's not 16 by 9. Focus on the digital ripples.

vimeo.com/765723
Watch from 13-36 seconds and you will see a ton of what i'm talking about.

Do you see the ripples and the flickers in the content. I just downloaded his original file, unfortunately my computer was too slow to really play it, so I can't be sure it's not the encoding etc. but this is the kind of thing that was in my original content that I was editing in FCP. These ripples and flickers in the moving image is the problem I had. The whole purpose of video cameras is to record moving objects, something it seems this camera or at the very least my camera and this guy's camera has problems with. I'm trying to get to the bottom of this problem before buying any new camera. Any thoughts, help, or advice is appreciated. I'm not trying to rain on the HV20 parade but I was disappointed in this particular issue.

If there are any experts on this, please chime in. And if there are any other HV20 users with this problem, please join the thread.
Brian 4 months ago

Google up "cmos rolling shutter".

Did you have a slow shutter speed?

Video'ing lightning or flashing displays is also really bad.
Mutcluck 4 months ago

I was mostly shooting automatic 60i with the cinemode on. That was it. I've seen and read about the typical cmos rolling shutter issues. Jello effect, partial exposure, and the, problem with fast movement and making vertical objects appear slightly bent. This is something entirely different.

I can actually see a line ripple up the footage. It's as if I can see a faulty scan/exposure line that somehow moves up the image. It seems to occur with slight camera movement, but the shot might be relatively stationery with some movement when handheld. It absolutely ruins the footage for me.
Brian 4 months ago

When I looked at the video at work (on LCD monitor), I saw a ton of what you were talking about.

When viewing at home on CRT monitor, I see a great reduction of the problems. When playing full screen, I see maybe 1... When I downloaded and playing with Creative Media Player or WMV player, I don't see any rolling shutter.
Mutcluck 4 months ago

Hey Brian,

Check the link below under forager's comment. This one is confirmed to have the digital ripple in the original footage as well. Maybe its a better example.
forager 4 months ago

The rolling shutter problem is
absolutely real.

The HV20 does not like any form
of direct mechanical vibration.

Also it does not like being buffeted by wind etc.

I found all this out whilst hanging
outside a chopper
on the second day I had the HV20.

The best solution is to hand hold rather
than to attach the camera to a mount which is
attached to a mechanical device such as a car.

This is a weakness of the camera
and some say of all
cmos sensors.
Mutcluck 4 months ago

Thanks for the reply. I've been only hand holding my work and the digital ripple occurred in tons of my footage. While the jello, partial exposure, and slanted vert issues due to CMOS rolling shutters aren't great, I don't notice it as much and haven't seen it in very much footage that isn't intentionally trying to cause them. The digital ripple I'm talking about jumps out and corrupts the image and shatters the illusion of watching "reality". That's a more serious issue for me. I hope I'm crazy, but I think I've seen it in EX1 footage too. Hopefully it's not true, cause I really want it to be my next camera, but I won't buy it, if it might produce the digital ripple problem. Here's one that has the problem in a couple spots. Here it is.

vimeo.com/774692

digital ripples in the footage of the woman in orange at 2.12 - 2.22 and at 3.12 with the kids sliding down the handrail. The creator confirmed it's in the source material when I messaged her.
Brian 4 months ago

i can see the horizontal scan line go through the middle at work on my lcd.

i'll see what it looks like at home.
Brian 4 months ago

Yeah - I don't see it on my CRT monitor at home.
Mutcluck 4 months ago

Not in the one I put up above? The creator said it was in her original footage at the two points I specified.