Wobbly image?

I hope you guys can get your PAL lands 25p cameras fixed so not so wobbly/shaky. Could there be any electronic part of the image stabilising that is coming unstuck in 50Hz mode(s), as the code was probably written for 60Hz - just putting some ideas out there, I have no real idea why it is happenning.

I sincerely hope that the HV20 50Hz 'wobbly' is not going to be a problem like the recent Sony 25p HVR V1E color debacle, but that alone got me scared enough to buy a 60Hz 24p HV20 (even though based in the UK) - because of my following thoughts: like in the world of video game consoles, these cameras are developed in NTSC lands - and any PAL compatability is an afterthought. Is that too strong a statement? Not if based on my video game console analogy - a multi million pound buisness where PAL was repeatedly shafted. I hope I am not dismissing the ability of these camera to do their 25p job, but the examples are stacking up of something wacky in bringing these camera to 1080 50Hz worlds...

GAME'S GUIDE TO 60Hz GAMING
 
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jenningsp said:
i've got it now. how would i test it?
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Take it for a walk at full wide-angle, put it on a simple stabilizer if you have one. If you have the same problem I have with wobbly image you will notice it sooner or later.
Also, shoot some really poor light footage so the camera has to add lots of gain and look for a blue vertical line a little to the left in the picture. If you have this problem you will even see this line in the display when you are recording.
 
so does this just seem to be a 24p low shutter speed thing? maybe just a few bad cameras? I read a post and the guy said at 1/48 24p everything was ok.
 
hi norbert

heard any info on this "wobbles" is this just the way of the camera cmos hdv
ois etc or is this faulty cameras i am contacting my dealer in uk to see if anymore complaints regarding this issue cant seem to get any info from
canon uk as i would like to know your thoughts and everbody elses does
the ntsc version have the same"wobbles"or is it in pal land only and are people returning them for exchange etc


thanks
 
here is my test of trying to walk as smoothly as possible and keeping the camera steady with two hands. you can hear my heavy breathing as proof that i tried really hard to get a smooth image :)

CINE MODE - F/5.6 - 1/50 shutter

http://www.box.net/shared/g9fxc3xs9n

it seems that this is just an inherent issue with the bayer filter on the camera, all bayer filter cameras suffer from it (PAL and NTSC), it's not a fault. here are some other discussions about the same thing.

current
http://www.dvinfo.net/conf/showthread.php?t=92486

older
http://www.dvinfo.net/conf/showthread.php?t=89865
 
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I had a different opinion before. After downloading all the files (or almost), my guts are:

There's some with these PAL version units -- too much sensitive in terms of roller shutter comparing with other units. Austin Meyers' sample, for instance:

http://dvinfo.net/conf/showpost.php?p=668760&postcount=15

Is there better example?

The question is:

Is there or not a noticeable difference between NTSC vs. PAL versions regarding the roller shutter issue?

Taken these examples I'd say: YES.

To notice that there is a similar problem with the NTSC version units, it's to put a mask on it. 'cause of course the CMOS is there too, the roller shutter as well. But taking both examples (Norbert vs. Meyers) there's a great difference.

What's up? Defective units? Or "just" a defective PAL manufacturing?

Unless, other units may prove this conclusion as a wrong conclusion.


Norbert, I'm waiting for your feedback on your replaced unit. If you'll have the same result with a quite different serial number, I'd advise any future PAL user (going to 25p route) if the NTSC wouldn't be better to the progressive purpose and speed-up 4% from the 24p all the shooting material (there's a problem under the fluorescent lights flickering that I'm not sure if it has solution since there's no 1/50 shutter speed or am I wrong?)


[Canon should present an urgent satisfaction to the PAL customer on this. They shouldn't be silent 'cause we won't.]
 
The rolling-shutter image artifact is well known, and yes it skews lines on horizontal pans. There are some nice extreme examples on dvinfo that show when the rolling shutter becomes more of an issue such as shooting a ceiling fan, etc. None of that really matters too much in actual practice; I mean, how many times will you shoot a ceiling fan or desk fan?

Where it could be a problem is under circumstances like flash photography, especially with lots of flashes going off; I would think maybe something like red-carpet interviews would be a worst-case scenario for a rolling shutter system.

That said, I can't see how the wobbles exhibited in Norbert's first clip would be rolling shutter. It just looks like the stabilizer was off and he had a case of the DTs while shooting. My HV20 has a rolling shutter and on full wide and handheld shot it is quite stable. So indict the rolling shutter for the things it is guilty of, but don't be so quick to blame it for things that may not be its fault.
 
The strange thing is that someone on dvinfo had the same problem (wobbly image like mine) with his NTSC HV20 a while ago when it had recently been released. So, are we talking about a few defective cameras from both worlds? Since it seems that not everyone has this problem.

A little update: I tried recording some DV footage with the HV20 on my stabilizer yesterday and it looked a lot better than the wobbly HDV footage I'm getting. Could it be a problem with just the HDV side of the camera?

I have yet to return my camera but I will get back to you on this as soon as I have tried the new one.
 
I completely agree with Barry. I've had my NTSC HV20 for about a month and the rolling shutter for everyday use is not a problem but could be in the scenerios he described.
 
Barry_Green said:
The rolling-shutter image artifact is well known, and yes it skews lines on horizontal pans. There are some nice extreme examples on dvinfo that show when the rolling shutter becomes more of an issue such as shooting a ceiling fan, etc. None of that really matters too much in actual practice; I mean, how many times will you shoot a ceiling fan or desk fan?

Where it could be a problem is under circumstances like flash photography, especially with lots of flashes going off; I would think maybe something like red-carpet interviews would be a worst-case scenario for a rolling shutter system.

That said, I can't see how the wobbles exhibited in Norbert's first clip would be rolling shutter. It just looks like the stabilizer was off and he had a case of the DTs while shooting. My HV20 has a rolling shutter and on full wide and handheld shot it is quite stable. So indict the rolling shutter for the things it is guilty of, but don't be so quick to blame it for things that may not be its fault.
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OK Barry and thanks for your reply.

But compare the Norbert's finding with these two Austin Meyers' samples:

http://file.meyersproduction.com/hv20/hv20 issues 720p.mov

http://file.meyersproduction.com/hv20/hv20 steady.mov

On the 1st it's the same thing but on the 2nd? There's no "the" same outcome. Why?

The most confusing is that we can't say the same when Norbert tries to smooth from his stabilizer. Still...from a slower move (comparing with Austin Meyers). It doesn't make sense at all.
 
Norbert said:
The strange thing is that someone on dvinfo had the same problem (wobbly image like mine) with his NTSC HV20 a while ago when it had recently been released. So, are we talking about a few defective cameras from both worlds? Since it seems that not everyone has this problem.

A little update: I tried recording some DV footage with the HV20 on my stabilizer yesterday and it looked a lot better than the wobbly HDV footage I'm getting. Could it be a problem with just the HDV side of the camera?

I have yet to return my camera but I will get back to you on this as soon as I have tried the new one.
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Are you talking about this one?

http://dvinfo.net/conf/showpost.php?p=668509&postcount=7

In his opinion, it's not a defective unit problem.

'cause if it is about Austin Meyers, compare your sample with those links one post before and you'll agree that if it appears on the first one, the same doesn't occur on the 2nd one. But not on yours. Yours is frankly worst. Why? (here's the question)
 
This is the thread I was talking about: http://www.dvinfo.net/conf/showthread.php?t=89865&highlight=stable
So yes, it was Austin Meyers. Look at the sample clip he has posted in the first post. It shows the same kind of distortion that I'm getting.

Austin Meyers said:
i am doing my best to hold it steady, but you'd think at full wide one should be able to hold the camera (the way it's meant to be held) and have it render useable video.
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This is what I would say too. No matter how hard I try I can't get useable video, but everyone seem to dismiss his footage as just regular shaky handheld footage. I really hope this issue is not normal for this kind of camera.
 
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Yeah, I agree. That's the same link I posted two posts above. However, his stabilizer footage (2nd link) doesn't show it. Why?

When will you have your new unit, Ron?
 
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