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Sony HVR-Z1 / HDR-FX1
Pro and consumer versions of this Sony 3-CCD HDV camcorder.

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Old August 23rd, 2005, 05:59 PM   #46
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That may be true, I can't say, but then how do you explain the problem demonstrated with both my postings, and Boyds? What have they done to mount their camera's..? Maybe the pitch of the engine doesn't have that low rate vibration that seems to set the problem off. This problem is not in our imaginations, it's real.
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Old August 23rd, 2005, 05:59 PM   #47
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Ken, I did those tests so we'd have something concrete to discuss and also because I have a Z1 and am curious as to its limitations. I'm curious to see how others react to these as well. I'm not sure that I share your conclusions however. To make a better comparison I'd need to use the VX-2000 on that same very bumpy road at the same speed. As I suggested, the images from that camera are a few years old and I was trying to minimize camera shake whereas I tried to maximize it with the Z1.

However, the doubled image of the mirror that you point to doesn't strike me as having anything to do with HDV or MPEG. It looks just like what I'd expect from a big jolt to an interlaced scan camera. In other words, that's how much everything moved during the 1/60 second between the capture of the odd and even field.

Have you ever seen the examples at this site? http://www.100fps.com/

They are all SD images and I see the same kind of things there caused by vertical movement, like this one: http://www.100fps.com/bigger.jpg

Douglas Spotted Eagle replied to your post, but somehow it ended up in the wrong thread when Chris was splitting things, did you catch this?

http://www.dvinfo.net/conf/showpost....78&postcount=4

I'll be curious to hear how others react to these examples. Personally, I'm not seeing anything which would rise to a "major problem with HDV format". Instead, it seems more of a "major problem with interlaced video." With the VX-2000 example, the 16:9 is created from only 360 scan lines which means you have something very soft to begin with, and my sense is that this minimizes the problem because you don't see so many discrete interlace artifacts.

Getting back to something Chris mentioned, I wonder if you wouldn't be a lot happier with an XL-2 or a DVX-100a. Aside from the 16:9 issue, they both shoot true progressive scan so you wouldn't see this sort of image doubling. However, I suspect that what you would see is just a big blur which encompases the full space between each of the "ghost" images in my example, since all 480 lines are captured at the same time.

Regardless, I'm glad that I've helped form your opinion even if we don't agree on the interpretation. Sharing information is really what we're about here at DVinfo. And no, I don't have anything against you but I think we just have a little different view of the world :-)
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Old August 23rd, 2005, 06:04 PM   #48
 
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Quote:
Originally Posted by Ken Eberhard
That may be true, I can't say, but then how do you explain the problem demonstrated with both my postings, and Boyds? What have they done to mount their camera's..? Maybe the pitch of the engine doesn't have that low rate vibration that seems to set the problem off. This problem is not in our imaginations, it's real.
Ken, I'm not in the least suggesting it's in your imagination. I would suggest that you're overreacting to what could be any number of problems. Frame rate set really high? That wouldn't help things much. Mounting got any absorption? that would be a problem. Steady shot on/off? Set to what setting?

To take the question the other way, how do you explain NASCAR and others using the format successfully?

Vibration on any compressed format is going to have some negative impact, but it's no where near as egregious as you're suggesting, IMO.
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Old August 23rd, 2005, 07:38 PM   #49
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This is all quite odd. If it was just an interlace issue, wouldn't it have been as prevalent in the PD150 or VX2000 or whatever Ken used prior to the Z1?

Even so, with the degrees of steadyshot available on the Z1, it would certainly seem possible to isolate and eliminate vibration-induced footage problems.

From the title of this thread ("Sony admits fault with HDV format" or whatever) I expected it to be an announcement about the format itself, such as this one:
http://www.sonydigital-link.com/dime..._tape.asp?l=en

That's a blanket admission that 1/2-second dropouts are happening in, and peculiar to to the Sony HDV format and are sometimes unrecoverable.

Ken, have you considered using something like the CineSaddle? I would be surprised if it didn't absorb the vibration and deliver glass-smooth footage.
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Old August 23rd, 2005, 08:04 PM   #50
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I don't fully understand Ken's situation, and since I'm not ready to upgrade to QT7 yet I can't watch his video.

However in the test I did, the issue wasn't "vibration." It was big bumps that caused the camera to shake up and down. I was trying to create a worst case scenario. Frankly I was surprised because even in that worst case I just saw pretty normal looking interlace, and not big blocky MPEG artifacts like others have complained about. I think the vibration is being well handled, as shown in this image where I was also driving down the same sand road at the same speed between bumps:

http://www.greenmist.com/hdv/dvbumps02.bmp

If I get time tomorrow I'll take the VX-2000 down that same road and shoot a few seconds for reference. But watching the video from the Z1 at 1280x720 on my 22" LCD, it really looked about the way I would expect from a bumpy road with no stabilizer....
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Old August 23rd, 2005, 08:30 PM   #51
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Quote:
Originally Posted by Barry Green
This is all quite odd. If it was just an interlace issue, wouldn't it have been as prevalent in the PD150 or VX2000 or whatever Ken used prior to the Z1?
I would think because the HDV format is capturing more detail, it would be more noticeable, where that sort of movement might register as blurry on SD.

What was the shutter speed?
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Old August 23rd, 2005, 08:50 PM   #52
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I can understand all the different feelings around this issue. Again, I want to state that I am way down here in lower Baja. I only have what I have. I have a PD 170 mounted on a GlideCam mounted on a Quad doing wonderful video, and unusable footage with the FX-1. Really, the GlideCam looks like it's doing it's job beautifully. When I first look at the extended end of the lens while in motion. It looks like a bird in flight. I have to bend over and look with my glasses on to see if there is any vibration at all. It is microscopic. Yet the picture is distorted. The same exact mount with the PD 170 is as it appears to the naked eye, it flies right along like a dream, it's a lot of fun to shoot with. Up rugged terrane and over washboard dirt roads. I am taping some of the most beautiful areas on the planet. I am building a wonderful new studio with 360 degree views of the ocean and the mountains. I have several hundred grand into my set up. This is a small item to replace on the grand scale. I'm just frustrated from being so far away from service and options. You can't import anything into Mexico without a 32% import fee. So the only way to get anything of value here is to either fly in and out with it in your hand, of drive the Baja's full length with it. It takes time to get things resolved down here. I have a lot of good things to look at, about the time my new studio is finished, I'll have resolved my camera issue one way or another, for me it's another format, and get on with documenting one of the most pristine area's left on the planet. I don't feel sorry for me. I'm the luckiest man I know..

My final thought is that the compression is unable to handle the extra data that happens when the lens is vibrated at a very minor level. It just doesn't have the capacity to develop all that tiny detail and resolve it like an uncompressed format.

In any case, that's all I know... I have the two cameras and the difference is one is usable, one is not.

Thanks, and sorry for my limited perspective. Ken
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Old August 23rd, 2005, 08:57 PM   #53
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One question: are you shooting with builtin 16:9 mode on the PD-170? If so, the camera is taking 360 lines and up-rezzing them to 480. On the FX1 it takes takes 1080 lines and down-rezzes them to 480....
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Old August 23rd, 2005, 09:16 PM   #54
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No, I'm using the 170 locked down on manuel focus, manual zoom, full wide angle with a wide angle adapter. No steady shot, it will leave artifacts even on the 170, but only a pros eyes will see them in most cases. The same with with FX-1, fully locked down, no steady shot. Steady shot really looks bad, the greater the setting, the worse it looks. Really, I've tried it all and discussed it all with a lot of people. And again, I'm kind of trying to sign out of this thread. I've covered all these issues in previous postings. And if you had looked at the posting of the PD-170 you would see I am shooting in 4x3. No offense meant, this is a long thread and it's hard to get it all. The 16x9 footage on the one posting is the FX-1 footage shot on a tripod, (beautiful by the way) with the PD 170 4x3 composited over the 16x9. Later in the video you see the PD-170 full screen in many different terranes. It really works great.

so you don't have to go search, one more time..

Good footage: http://homepage.mac.com/kene3/QuadHeaven.html (no problems here)

Thanks again.. Ken
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Old August 23rd, 2005, 09:45 PM   #55
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Sorry, I can't watch the video because it needs Quicktime 7; can't upgrade to that because it will break other stuff on my system.

Good luck with your project, it sounds very cool.
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Old August 23rd, 2005, 09:49 PM   #56
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All I can say on the matter is...

The samples look exactly like what I'd expect. I certainly wouldn't use my FX-1e in similar circumstances without making sure that ALL vibration regardless of it's frequency was totally eliminated, regardless of the sort of camera I was using.

To suggest that the 'effect' seen is a major problem with HDV is somewhat of a leap, given that it's more of a problem with eliminating the specific vibration that appears to be the cause of this seeming issue. If the problem was one with HDV in general, it would show up for you at all vibration levels - but you've even stated that it is at a specific vibration frequency.

For my 2c worth; that means the problem is with the vibration frequency and how it causes the whole camera system to perform/compensate for something I'm sure the designers never envisaged as a common usage condition. As for putting my FX-1e on an operating clothes dryer to see what sort of image I'd get compared to a similarly set-up SD camcorder...that wouldn't be something I'd do because I know what I'd see, and it would be beyond the standard operating conditions for either camera. If I did so, I would do so knowing that I have pushed the boundaries of each cameras' terms of use - and I'd need to take my own precautions to ensure the unit operates as close to those intended, and be aware of my responsibilities in doing so.

Hopefully you will be able to test one of the newer HD/HDV camcorders under the same circumstances, however I suspect that serendipity will play an essential part in finding a HD/HDV camcorder that will perform adequately under the same conditions/scenario.
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Old August 23rd, 2005, 11:32 PM   #57
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Just a quick observation...

To me, the HDV clip that is used as an example to my mind actually gives a more accurate impression of the reality of the vibration to be experienced on your ATV, than the SD stuff in your promo video. As the clarity is also greater in the FX-1 clip, the overall image quality is also superior - despite the vibration. I'd bet the ATV really does vibrate that much through it's rev range. I can see that such accuracy could be a bad thing.
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Old August 24th, 2005, 09:36 AM   #58
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As you can see, I'm not out of here yet... Boyd, I am loading a WMV file to my site now. Although I have to warn you, it's 45 megs compared to the 16 meg QT file. My experience with QT7 has been great. I even upgraded before I got FCP 5. It worked great even when I didn't have QT Pro... I did lose some export options that you may find you can't live without. Then again, for thirty bucks you can upgrade to pro without buying FCP 5. I did it because we use iChat video a lot with our family in the states and it's a significant upgrade. FCP 4 worked fine with QT 7, none pro version. I'll post the link when I get this huge file uploaded. I hope you have broadband... OOPs? I just got it loaded and it wont play. Do you have iChat working. We can exchange large files that way.. my iChat address is ...

"All I can say on the matter is":

I have done as you suggested. Again, the GlideCam is fantastic. All visible vibration is eliminated by that wonderful device. And again, consider my perspective. To me this is a huge problem. It eliminates almost every application I would want to use it for. Not only the Quad video's that are my bread and butter now. But I am also planning on going out on fishing expeditions after Marlin and game fish. The problem would eliminate my ability to use a tripod on a fishing boat. Only hand held or vest mounted GlideCam would work, doable, but to lose a tripod shot would present it's challenges. So for me to use the term "Major Problem" is an absolute truth.

2c worth: Yes, the problem is with vibration frequency. Like a slightly rumbling car, a boat, a helicopter, and yes an ATV. Yes, my use is beyond what they designed the product for... However, if I had the camera here now, I would go out and film the camera in motion with my 170 and show you how smooth this mount is. My concern has never been about the tinny vibration, I never saw it until I had the problem with the FX-1 and I bent over with glasses on to see it. It's about dust, or an accident. I know I am taking chances with the camera. But even in the worst case I crash and destroy the camera completely. Well, if I make twenty grand or more with the product, it works out. I never would have put a fifty grand camera in the same place. The FX-1 cost around the same as my PD-170. A reasonable risk for such gain. I am aware of the fact that I am pushing the accepted boundaries of the camera. Again, I wasn't going to send this camera in for repair. I was going to accept it and move on. But this forum came to the conclusion that the camera had a repairable problem. So I sent it in, and that takes months for me to do from down here. And no, I will never buy another HDV camera again. The MP2 encoding has it's limitations, according to me. I feel confident that a none compressed HD would work fine. And with the new panasonic coming out with a price range of an acceptable risk, I'll buy one and do it with it, after I test it that is. Besides, I'm having fun doing these video's. I've got a list of projects waiting for me to do for the QuadMan who runs a big business down here. It's profitable. Although at this point in my career, I don't want to work much for others. I like being my own producer. But it's fun and I'm making money doing it.

Steve, I have to disagree with you about the clarity of the HDV stuff under the vibration. It appears as a mushed up mess. It looks like the auto focus is running amuck. It's completely unusable. The 170 has a great picture, and yes, the resolution of the HDV is fantastic. I love the quality of the pictures on a tripod. It's truly a great breakthrough. HD at SD data rates, wonderful. But be aware, according to me, it has it's limitations.

Adiós, Ken

Last edited by Ken Eberhard; August 24th, 2005 at 02:09 PM.
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Old August 24th, 2005, 11:04 AM   #59
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<< I never would have put a fifty grand camera in the same place. >>

Fear not Ken, I myself have flown cameras worth five times that amount in exactly the same way. ATV Steadicam mounts are very common, been around for years and assuming they are properly rigged and secured and the driver is responsible, perfectly safe to operate.

Not to say accidents can't happen, of course; it's a small motorized vehicle! I myself had a component break in my arm during a particularly strenous set of G's about 5 years ago and the rig was thrown off the back. Insurance covered the damage and I got some shiny new parts for my rig. C'est la vie.
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Old August 24th, 2005, 12:28 PM   #60
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I knew someone who was shooting on-board sport bike footage with a low-end z-something canon who was getting pretty nice shots. He then upgraded to a Panny GS400, a camera that I personally own and love, and got complete garbage out of it on his bike. The vibration made it completely unusable. In the end, he discovered that OPTICAL stabilization on the GS was a big part of the problem whereas the electronic stabilization on the Z cam actually worked much better. He ended up returning his GS because the only options on that cam were optical or nothing, and niether worked particularly well. He went back to cheesy cam with electronic and actually got better results. This probably has nothing to do with your setup, and I know nothing about the 170, but I thought this was worth mentioning in case it helps in any way.
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