Wobbly image?

[Norbert]

I have recently got my HV20 and I love the image quality. However, I'm trying to figure out if there is something wrong with my camera because as soon as I move the camera I get an extremely wobbly image that resembles a jelly, even at full wide. Not even the OIS takes care of these wobbles.

Here's a handheld clip full wide with OIS ON where I am walking up a hill: http://files.filefront.com/7340877
Should it wobble like that?

I put the camera on a home made stabilizer device and tried it with both OIS on and off, but that did not take care of the wobbles either. Here's a clip with stabilizer and OIS on: http://files.filefront.com/7340999

I have an old Sony DV handycam with EIS that produces far better results even with the EIS off. I've also owned a DVX100 with OIS which did not behave like this either. I've never seen anything like it before.

Am I just spoiled? Is it supposed to behave this way? Or is there something wrong with my HV20?

[Mal]

Can't check the footage as the download is way too slow.

Something seems odd though, as I have not noticed anything weird about the HV20's OIS.
Generally speaking, if you have the cam in a moving motion (walking handheld, moving stabilizer, or panning on a tripod), you'd want to turn the OIS off, as you will get jerky movement/jitter.
Of course, you are saying you get this odd behavious with or without OIS. so it does seem off.
Are you sure you are not seeing the jitter caused by wrong framerate/pulldown?

[Norbert]

Smaller files uploaded on Filefront. First post edited. ^^
The strange thing is I don't see these wobbles when I take my old Sony for a walk, with or without EIS.
It's not a pulldown problem either, I have the PAL version. I see these wobbles when I connect the camera to my tv as well.

[ib84]

I can see it, it´s indeed very strange...
can´t figure out a reason for this with the things you said, but most likely something is wrong with the OIS controll, like the arrestation of the moving lenses. I would send it back...

you could try for the hell if there is even wobble when you have the cam completely still and just filming moving objects... this could indicated a software error

I am very interested in this one, as i am about to buy me the HV20 in PAL-land too...

good luck

[Norbert]

It doesn't show any of this behaviour when I shoot moving objects with the camera being still. It's when I start moving the camera this happens. I tried panning slowly on a tripod and I don't think I saw any jerkyness there. The problem is I don't want to be restricted to a tripod, so I will return this camera and get a new one that hopefully doesn't behave like this.

[ib84]

i am afraid this is not a single case:
here is a guy complaining about the same thing, i guess. look at the
video, it´s the same kind of wooble image.

And another video in which you can see the wooble... (restricted access on listvideo)

so is this normal and all the others just don´t see?!?!

I am disappointed this exist also in the PAL-version...

[Norbert]

Yeah I saw those earlier but I thought the problem was fixed now or that their units were just defective because no one else seemed to complain about it. I'm sure some people out there are okay with this problem, thinking that the camera is supposed to behave like this. I would probably be under that same impression too if I hadn't used my old Sony from which I can get a far more stable image.

I have seen footage that doesn't show any of this wobblyness however so I guess there are just a few cameras that have this defect. I really hope to get one back that doesn't have this issue.

[Mal]

Norbert,
I must be thick, because I am still not fully understanding the problem.
From what I gather, you can walk handheld with a Sony cam and it has usual "shaking" from walking, but with the HV20 it is much worse and wobbles?

I just tried two shots, one with a Sony MiniDV cam, the other with the HV20, and they are both equally bad, I'd say.

I watched your clip, and although I can see the shaking, it doesn't immediately strike me as MUCH worse than what I'd expect from walking handheld.

WAIT, I see you used a home made stabilizer? Darn, yeah, that should be better then.
I guess a comparison to another cam would of helped.

In any event, I'd really like to know what exactly is going on here, and if some of the cams are simply defective, or what.

[Mal]

Okay...doing some own testing now...results in a few minutes....

[Mal]

Okay, seems this is indeed something that's going on with this (or other HDV cams as well). I can duplicate it somewhat, but not as bad as Norbert's footage.

I haven't pin-pointed the exact problem yet; it may be CMOS/HDV/shutter speed related.

There was a site that posted stills that had vertical lines all warped. Anyone remember where that was? Might be something completely different, but I recall it had to do with how the CMOS was exposed when the cam was moving.

This is obviously something that needs to be solved or at least have a workaround, even if it means we can't move fast with this cam.

I've quickly uploaded NORBERT's footage with the original file, and one that is corrected slightly with STEADYHAND - a software program). This was done so I could see what was going on while having the "normal" shakyness removed. On DV footage, this program works very well, however, on Norbert's footage this is what it looks like:
http://hv20.info/yopu/wobble2.mov
(1.7MB, Sorenson3 MOV file)

[Mal]

Well (I THINK) I can confirm what's going on now.
This seems indeed to be this vertical-line-getting-warped problem during fast pans. I wish I'd remember where I'd seen those stills...

A simple test should illuminate this problem, and be duplicatable:
take the HV20, hit record, and wave it side to side, while trying to keep the cam as straight as possible (don't TILT the cam, just waive it left to right to left).
Then import that footage, and what should be vertical lines comes out all bent like.

Now, although this sounds grave, it might not be, especially if this might be completely avoidable with some adjustements.

Has to be further investigated....

[24Peter]

My take on the issue (from the other forum)

"For me I've chalked it [wobbly image] up to three factors that are NOT IMO defects (at least defects that can be fixed) of the camera: 1) small, lightweight cameras are inherently more difficult to hold steady. I'm coming off a DVX100. With all my stuff on it, that camera was around 5 lbs with that mass spread around a much larger camera. The HV20 is tiny in comparison. It weighs close to what my extended life battery weighs on the DVX - just the battery! 2) HD(V) resolution - most of us are used to standard DV resolution. The HV20's resolution is 2 1/2 times greater. Thus small camera movements appear greatly amplified. While a camera shaking 1/8" in either direction is still 1/8 for DV or HDV, to me at least it looks much more pronounced in my HDV footage. 3) CMOS sensor - I'm not an engineer and others are probably much more knowledgeable than I on this, but my understanding is fast camera movement on a CMOS sensor shows up as kind of diagonal sheering of the image. To me at least this makes camera movement much more noticeable (subject movement, on the other hand, appears the same to me on the HV20 as any other camera). But I can get literally seasick watching some of my HV20 handheld stuff where I moved the camera in a jerky fashion to begin with.

Canon's OIS works quite well IMO. But any lens stabilizing system has it's limits. (BTW - I leave it turned on even while on a tripod to "absorb" any bumps - may turn it off for lots of panning as supposedly it has a negative effect on pans though I have yet to see it.) But based on 1)-3) above, I've come to the overall conclusion that I can't do a lot of handheld shooting with the HV20 esp at the long end of the zoom. I recently got Canon's wide angle adapter - WD-H43 or whatever it's called - hoping that 1) shooting wider would make my shakey camera moves less noticeable and 2) the added weight of the adapter would make the camera more stable. But no go. On 2) all the adapter does is make the camera noticebly front heavy. All that weight on the front acts as a lever (remember high school physics?), amplifying the stability issues of the camera (for me at least).

So... I've resigned myself to shooting a lot more with a tripod with this camera and looking for some other means to stabilize the camera when shooting handheld. But I think shooting while walking is definitely out for me with this camera!"

[Mal]

Well, 24peter, I was with you on all points, but looking closely at Norbert's footage; using my own comparisons with the HV20 and a MiniDV Sony cam; and with watching the HV20 footage AFTER the usual shakyness was removed (with Steadyhand software); I can conclude, that what Norbert is talking about....

has nothing to do with 1) nor 2) of your post!

#3 however, yes, that's indeed what's going on.

Now, I don't want to discount your 1) and 2) completely, as they will naturally effect the outcome of the resulting footage. But this is DEFINITELY not what Norbert is so upset about.

It took me a while to see this, I admit; and I needed to take away the normal shakeyness first. Check that clip that I uploaded; it's an eyeopener!

(Not trying to be smart about this, just trying to get to the bottom of it....)

[Norbert]

I would like to get to the bottom of this also. Maybe I should load the battery for my HV20 again and make a direct comparison between that and my Sony minidv camera, both on my stabilizer, before I return the HV20.
I should be able to get a far more stable image from the Sony. I'll be back with clips ASAP.

[Mal]

Yes, that would be great, Norbert.
If possible, remove the "normal" shake with Steadyhand (trialversion).
That way you should be easily able to identify the wobble.

Wobble, by the way, is the perfect description of what's going on.
Unfortunately your identified problem easily gets dismissed as usual handheld shakeyness, which it isn't. Running the SONY DV footage and the HV20 footage through Steadyhand will easily show the difference.

EDIT: by the way, to make it easier, I reduced both the HV20 footage, and some Sony footage to SD (DV) for import to Steadyhand, in a quick test I did yesterday.

[Norbert]

I will do it first thing tomorrow.

When this wobbly footage gets dismissed as just usual handheld shakyness I start to wonder if everyone has this problem with their HV20 without realizing it's a problem. If that is the case I hope someone will contact Canon and convince them that this is a problem that needs to be fixed.

[Mal]

...I hope someone will contact Canon and convince them that this is a problem that needs to be fixed.

I agree, unless it's simply something inherent with a CMOS and HDV?
Canon won't be able to solve that one easily.

Since I am now convinced (maybe erroneously) that this will only happen during fast horizontal movement, one could argue of course, that using a stabilizer of some sort will eliminate the problem.

Also, it would mean that [horizontal] pans would have to adhere to below certain speeds. But given that we are forced to do these low speeds anyway if we use 24p (or 25p), that one is not such a big issue at all.

[Norbert]

Is the HV20 the first HDV camera to use a single CMOS?

I think you'd have to define a fast horizontal movement. I don't have to walk fast at all to make the image wobble. As soon as I take the first step even with the stabilizer on a plane surface like a floor, the image starts to wobble, no matter how fast or slow. Heck, I got a more steady image out of walking with my old DVX100 over large rocks and fallen trees in the woods using only a tripod as a stabilizer.

The kind of stabilizer I have built will reduce horizontal movement but it doesn't reduce vertical movement just as good. It's like the FigRig only without the ring. Still, I can get pleasing results (to my eye) with my old Sony on that stabilizer but not with the HV20.

I haven't had any problems with pans on a tripod however. I will try a really fast horizontal pan tomorrow as well.

[Mal]

Okay, let's break this down REAL SIMPLE.
One thing at a time.

Let's forget the whole handheld thing; I think that is unnecessarily complicating & confusing the matter.
It happens to be where this was "discovered", but we shouldn't look at this from that point of view.

So here's a little experiment:

HV20 (USA model) from 5 minutes ago.

HV20 on a TRIPOD.

Sturdy.

Level.

Now, this is what it looks like panning slowly or standing still:


This is a screen capture of what it looks like panning fast:


So, this line obviously should stay vertical, not bent like that. The faster the pan, the more bent that gets.
This is well illustrated with a vertical line; but of course there's the same thing going on with any subject.
That's why when you look at Norbert's modified clip I posted, you will find it all wobbly/spongy.

I believe shutter was at 1/100th sec, in 24p mode.

Here's a movie of this experiment slowed down to 30% (THIS MEANS THAT THERE WAS A SIGNIFICANTLY FASTER
PAN BACK AND FORTH THAN THIS. Sorry, don't mean to shout, I just don't want anyone to think
that this was the ACTUAL speed. It wasn't.):
http://hv20.info/yopu/shakey.mov
(about 1,7MB, Sorenson 3 MOV file, not pretty, terrible shot, but it's the wobble that counts!)

So, this is what's happening.

[Melachrino]

Mal: Nice test. Sacrebleu!

Is this a 24p processing artifact ?

I went to my local dealer a couple of hours ago and re-tested the HV20 for the wigglies and the diagonal lag. Nice vertical and horizontal references, good lighting in the store. Indeed, panning showed the effect desribed to some degree. However, the camera was in HDV24 mode. I switched it to HDV and the wigglies were gone, and motion rendition was as good as expected. I could not test in low light to check for shutter/iris processing artifacts causing the wigglies.

(In addition, I retested the OIS and worked excellent for my conditions. Turning it off, showed all my usual shakes and rolls... The three focusing methods also worked marvelously. Instant focus, a plus, normal focus very good if you do not want the focus jumps, and manual focus with focus assist is a winner in my book.)

There is another possible cause of the diagonal rendition and it may have to do with any form of noise reduction or any other use of field or frame memory to produce a picture. When the recirculation factor is set high, to reduce noise or combine stills, you get lag and ghosting. I cannot think of any mechanical or correctly done MPEG2 processing that can do what you show. That is why I am suspicious of the 24p mode you show in your test. Can you try it at 60i to prove me wrong ? (That is how I learn...)

[Mal]

That is why I am suspicious of the 24p mode you show in your test. Can you try it at 60i to prove me wrong ? (That is how I learn...)

Sacré bleu is right! (used spell check to get that right ---> my french isn't THAT good! )

I can tell you ARE wrong. I just did the same test and at 60i it does EXACTLY the same thing. To PROVE you're wrong I'd have to upload the footage, and it's too late for that, so you just have to take my word for it.

Funny, because I thought you might be on to something there....so I was a little disappointed when the same crooked lines showed up...

[24Peter]

My understanding is the whole diagonal sheering effect is just the nature of the beast right now with the CMOS sensors. Hopefully, they'll come up with ways to compensate for it in firmware. Or else in future versions of the camera.

[Mal]

Yes, I think that's exactly it.
I honestly think for most stuff, this is NOT going to show anyway.

[Norbert]

Mal: I think you nailed it pretty much with your test. I haven't done the comparison yet but I don't think it's necessary now?

I agree it will not show for most stuff, but I want to be able to do steady shots with my stabilizer like I did with my Sony, so if the HV20 can't work better than this right now then I will wait.

Someone should definitely contact Canon and ask what might be causing this problem instead of doing all this reverse engineering.
If it appears to be caused by the CMOS censor, then shouldn't all Sony HC cameras have the same issue also?

EDIT: I did a comparison of the HV20 and my old Sony, both on a stabilizer just for the heck of it. As I expected, the footage from the HV20 looked far more shaky because of this issue we are having. However, shooting DV with the HV20 shows less wobbles if no wobbles at all. 25p HDV seemed to wobble a little bit more than 50i HDV, but my tests are not made in a controlled enviorment by a machine so it says nothing really. One thing is for sure though, out of all the test runs I did I always got more stable footage from my old Sony.

[nana ban]

he norbert

i was wondering with the amount of people having this same problem
did you return your camera do any of the dealers know about this i am
going to contact mine and find out if anybody has mentioned this in uk
and send e-mail to canon uk and see if any reply but i would love to know if faulty batch of cameras or is per normal for this new camera.