View Full Version : Wavy video from HV10 & HV30


Tripp Woelfel
September 14th, 2008, 09:22 PM
I have an HV10 & 30 that I routinely use as locked off B cameras to shoot motor racing. Intermittently, the HV10 would deliver video with a slight ripple from top to bottom. This was shot in HD but captured in SD. This wavy video would persist through multiple long shots and would only seem to resolve itself when I changed tapes or power cycled the unit. As an aside, I know it's not the tapes as I use the same tapes in my XH A1 without problem.

Until today, I thought this problem was unique to the HV10. But in capturing tonight's footage shot by the HV30, the same problem appeared on that camera. Although shot with the HV30, I captured it with the HV10 which suggests that it may be a capture issue rather than a recording issue.

Needless to say, I'm as confused as old Nick about this. Anyone have a similar experience or, perchance, an explanation? All thoughts would be appreciated.

Chris Soucy
September 14th, 2008, 10:29 PM
Long time, no speak!

Guess you'll have to eliminate the impossible here and re - capture the dodgy (maybe) HV30 tape using the HV30, to see if it comes right.

Further info would be gleaned by re - capturing a sequence using the HV30 that was shot on the HV10, which, when captured from the HV10, showed the problem.

Can't say as I've read of anything like this before, gonna be a bugger of a fault to track down and no mistake.

I'll stay tuned for the next exciting episode.


CS

Tripp Woelfel
September 15th, 2008, 08:27 AM
Chris... Yep. Here I am. Out from under my rock. Nice to see you again.

I'm actually capturing HV10 footage on the 30 right now. Same problem. I'm also capturing HV30 footage on the HV10 on another system. Same problem there too.

As a test when I saw this phenomenon, I stopped both captures. Re-booted both systems. Power cycled both cameras including disconnecting the power from the wall. When everything came back up the problem was still there. What strikes me as funny is that the problem shows up on both cameras.

I'm now wondering if it's a power problem at the track. I generally shoot the last part of the last race of the evening on battery power, packing up the AC power connections when I get a break to speed my exit at evening's end. I'll have to check that footage when I get to it to see if the problem is still present.

This would be easier to suss out if the problem wasn't intermittent by clip.

Jack Zhang
September 15th, 2008, 07:51 PM
It's either the rolling shutter effect (which comes standard with all new CMOS camcorders. Read all about it here: CMOS Rolling Shutter (http://dvxuser.com/jason/CMOS-CCD/) )

Or a bad CA-570 power adaptor or one that's taking in dirty energy. Canon cameras are notorious at power problems.

Chris Barcellos
September 15th, 2008, 08:22 PM
Here is my diagnosis. Vibration coupled with rolling shutter. Vibration maybe caused by motor roar from cars ??? Or someone bumping camera or support, or crowd around it. Also, sometimes the steady shot feature will react to vibration and movement, and with interaction with rolling shutter that occurs.... I have this occur time to time with a Letus vibrating 35mm adapter.

Tripp Woelfel
September 16th, 2008, 08:00 AM
It's either the rolling shutter effect (which comes standard with all new CMOS camcorders. Read all about it here: CMOS Rolling Shutter (http://dvxuser.com/jason/CMOS-CCD/) )

Or a bad CA-570 power adaptor or one that's taking in dirty energy. Canon cameras are notorious at power problems.

Jack... I checked out the article and my symptoms don't fit any of the examples. The closest symptom is "wobble" but it happens on one axis (north/south) and if you think about the wobble as a sine wave, it goes through about 1.5 to 2 cycles in frame and rolls from north to south.
>>>>UPDATE: This previous description is incorrect. The wobble is on both the north-south and east/west axes. I cannot accurately assess the frequency but my previous assessment seems in the ballpark. For an example of this wobble, go here: http://www.vimeo.com/1745751

I am increasingly suspecting the power. The speedway is as old as I am (read very old) and I suspect much of the electrics are near original. I'll have to check the footage shot near the end of the race when running on batteries to see if it shows up there. This will not be definitive confirmation of the diagnosis as the problem is intermittent when plugged into the power grid.

Tripp Woelfel
September 16th, 2008, 08:07 AM
Here is my diagnosis. Vibration coupled with rolling shutter. Vibration maybe caused by motor roar from cars ???

I strongly doubt this as although the problem is intermittent, when the problem occurs it happens at a constant amplitude and is unaffected by the rise and fall of the engine sounds as they travel from the near to far side of the track and back again.

Or someone bumping camera or support, or crowd around it.

Again, don't think so. Both cameras are on sturdy tripods and I'm the only guy up on the roof.

Also, sometimes the steady shot feature will react to vibration and movement, and with interaction with rolling shutter that occurs.... I have this occur time to time with a Letus vibrating 35mm adapter.

Image stabilization is off on both cameras so I doubt this too.

I'm going to grab a piece of this tainted video and post it online. I think in this case some pictures will indeed be worth a thousand words.

Tripp Woelfel
September 16th, 2008, 10:58 AM
OK... I've posted short samples of video with and without the wobble. These were both captured on the same tape, on the same date. The camera was mounted on a sturdy tripod and plugged into AC power in both cases. There is a wide angle adapter mounted on the lens but I don't think this is particularly relevant since the wobble has previously shown up without it it place.

Nothing about the camera is different between the two clips. The clip with wobble was at 17 minutes into the tape on the first start/stop cycle. The clip without wobble was at about 50 minutes into the tape and in the 7th start/stop cycle.

HV10 Video Wobble (http://www.vimeo.com/1745751)
HV10 No Video Wobble (http://www.vimeo.com/1745778)

If anyone has any thoughts, I'm all ears.

Chris Barcellos
September 16th, 2008, 11:22 AM
My thoughts were suggestion that you apparently have covered.

That's the same kind of wobble I have run into occasionally with my HV20-- and I rarely shot with a power adapter connected. I usually trace it back to vibration issues. Right now, for instance, my HV20's tripod mounting plate has developed looseness that I can't seem to tighten up, and I get some looseness on mounting it to tripod, and in certain situations, the vibration can be set off. As I recall the HV10 is taller and more top heavy, and may have less mounting contact area on the base.

But your set up looks rock solid on the trouble free clip, unless on the roof you are shooting from there is some kind of vibration that gets set into effect occasionally. (Wind, slamming doors, moving crowd below ??? )

I have also wondered about the stabilizing system in the camera, and if sometimes in the off mode, it could still have and effect. (Like an element is still floating in the camera.)

I am curious as to what you eventually track it down to....

Tomas Chinchilla
September 16th, 2008, 07:00 PM
This might sound stupid and you might have already tried it.

Have you tried just capturing in HDV (HD)? I see that you are using the in camera down-sampling

Just a thought.

Tripp Woelfel
September 17th, 2008, 08:49 AM
Yes. I've captured the downsampled SD video and the original HDV. The problem exists in both.

I could try capturing in SD, but I doubt that would change anything.

The problem with sussing out this issue is that you cannot see the wobble in the LCD because it's too small so the first you know you have a problem is when you're capturing to computer.