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October 31st, 2007, 07:43 PM | #1 |
Wrangler
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This is terrible -- this can't be right!
I just received my HV20 and took it out to shoot some test footage. I tried it in auto mode, program mode and "cine." I played back the footage via HDMI into my Toshiba Regza 42" HD television. Bear in mind that my basis for comparison is my standard-definition, 3-ccd Sony VX2000 camcorder.
I was shooting, primarily, trees in a park near my home. Basically, anything with high-contrast fine detail, e.g. leaves, strong verticals in bark, etc., looked just awful -- displaying the kind of motion and digital artifacts that I associate with Bayer-filtered sensors on inexpensive single CCD standard definition camcorders. These areas were, literally, vibrating with artifacts. What's going on here? Is this over-sharpening? Is this the best I can expect from a single-ccd machine? If so, it's going back and I'll wait until I can afford a Sony FX7 or a Canon AH1. The detail and color are fine, but I can't live with this kind of artifacting. This can't be right -- everyone is raving about this camera. Am I missing something here? |
October 31st, 2007, 08:10 PM | #2 |
Major Player
Join Date: Apr 2007
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could you post some stills?
I have a Hv20 and have shot leaves and other nature stuff with verticals and seems fine to me (i have an A1 to compare to) in Cine mode there is no sharpening of any sort so should be alot more smoother. |
October 31st, 2007, 10:01 PM | #3 |
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I captured some video into Premiere and exported it to a WMV9 file, thinking I'd post it as an example of what I was seeing. Now, this is weird: on my computer, it looks perfect! No artifacts. (Incidently, my 3 GHz P4 with 1 gig of RAM is barely up to editing HDV -- playback is jerky).
Now, I'm going to try a different test. I'm going to capture to my laptop and Premiere Pro, export to an AVI file and and play it from my laptop direct to my HD television (the laptop's docking station has a DMI port and I've got it connected to the TV with an HDMI to DMI converter). |
October 31st, 2007, 10:06 PM | #4 |
Tourist
Join Date: Apr 2007
Location: san diego ca USA
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I too was shocked at the pq. The color and sharpness of the HV20 is great, but pan on a tripod or track moving objects and I was disapointed with the artifacts.
In good light, I tested with a tripod and an open field of grass at the bottom of the frame and sky at the top. The horizon and sky look fine, but the blades of grass smear when you pan. Stay still and it's full color and sharpness. Move and it is a little jumpy and smeared. I take this to be a result of 2 things. HD pictures have more resolution and that sharpnes can be more obvious when the camera or subject moves. I think the biggest factor is the amount of compression needed to squeeze the HD picture into the mini DV tape bandwidth. Static pictures come through with a great picture, but a moving images show the limitations of how much data can be stored. I can be all wrong, but it was the conclussion that made sense to me. |
October 31st, 2007, 10:17 PM | #5 |
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I have the same problem when panning. There is tearing and smearing when panning. It doesn't look way too bad as .m2t at 60fps, but most NLEs will resample at 30fps and then it just looks bad, more than it should.
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October 31st, 2007, 11:31 PM | #6 |
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Well, some more mixed results -- my laptop isn't fast enough to play the rendered mpeg file in real time, so I still can't see the results on my HD television. This weekend I'll do some more experiments with sharpening turned off, 24p and component out from the camcorder to the television. We'll see, but I have a feeling this camera is going back.
Okay, I did one more test. I tried the component outputs and found that crawling and vibration is dramatically reduced, almost to the point of vanishing. I'm wondering if this isn't either an interlace issue or a pull-own issue. Oh well. More experiments later. |
October 31st, 2007, 11:45 PM | #7 |
Inner Circle
Join Date: Nov 2005
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Taking the camera back won't solve the problem. Plenty of people are getting fantastic images out of this camera. You need to learn a little bit about the camera.
In Cinemode, you can't actually control your shutter speed, unless you know a bit more about how to do it. In 24p, you want to be at 1/48 period. Try shooting in TV mode, and lock the camera at 1/48 shutter speed. You will lose the benefits of Cine mode, but gain more control. You can custom set the camera turning everything down to get close to a Cine mode look.. Second thing is that with any 24p camera, you need to extremely careful about quick pans or jittery camera movement. 24p needs a stable shooting platform.
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November 1st, 2007, 01:02 AM | #8 | |
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Quote:
I appreciate your suggestions, but I don't think they have anything to do with what I'm seeing. By the way, I have no interest in shooting in 24p -- I'm not trying for a film look. I'm quite happy with good, clean hi-def video. |
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November 1st, 2007, 08:11 AM | #9 |
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I was comparing my HDR-HC3 to my HV20 with moving video in this thread
http://www.hv20.com/showthread.php?t=3341 about post 9 I said I had taken my HC3 hiking and filmed while walking and the video came out fine, on a different trip I did the same thing with the hv20 and the footage was un-watchable. They were saying it is rolling shutter. I guess the sony cams are better for hand held stuff and the HV20 is a better tripod cam because it is sharper. |
November 1st, 2007, 09:15 AM | #10 |
Inner Circle
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Wow, my mistake, and my apologies. Somehow I got the impression you were shooting in 24p. I guess because you indicated you were using Cine mode.
Okay, there is no doubt this camera is touchier than my Sony's with respect to needing stabilization.... I don't know reason why technically. It definitely isn't a VX2000. Hand held, you have to have the stabilization on or you get some nasty footage. And stabilization should be off on the tripod. I leave it on with the monopod. In any HDV you face motion a issues that are accentuated by the codec, and add to that the additional sharpness of the image, and it all becomes more noticeable. I think my FX1, being heavier, is better stabilized. I also believe when stabilization is off on the Canon, something makes it more sensitive to bumps and sudden moves, than my FX1. As far as rolling shutter, I have occasionally experienced the jello like wobbly images in pans etc, but that isn't the norm. But lets face it, for now sub $1,000.00 HD camera, you will not beat the image and sharpness of this camera. Question: Do you have the same issue with component to your HDTV. And is it possible your settings on the TV are wrong. Other thing I suggest is actually editing capturing and editing in it to get a true feel for what it does. Don't dismiss 24p. It has a great feel to impart to your films...and handled right, this camera, at this price is a great entree into the 24p world.... and this is only reason I bought it.
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November 1st, 2007, 10:50 AM | #11 | ||||||
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November 1st, 2007, 03:19 PM | #12 |
Major Player
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Single cmos doesn't have anything to do what your describing. It sounds like your describing mpeg artifacts, but without any screencaps its hard to say. My hv20 produces beautiful images.
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November 1st, 2007, 04:02 PM | #13 |
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It's not the fact that it's a single sensor, but the fact that it uses a Bayer filter that can result in these kinds of artifacts. I've seen in standard definition miniDV camcorders which, of course, don't use mpeg or, for that matter, any form of temporal compression.
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November 1st, 2007, 10:28 PM | #14 |
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Okay, I've posted a frame that exhibits digital artifacts due to what I believe to be oversharpening. The artifacts are more visible if you zoom in a bit on the insets. It's particularly obvious on the cross-hatched palm tree trunks -- light, high-contrast areas have significant "zaggies" on the diagonal lines that are not present on the lower-contrast areas. The sharpening is most visible on the large palm trunk with the vertical striations. This appears to validate my initial impression that the artifact problem was confined to high-frequency detail. It also explains why the artifacts are more visible via HDMI than over component.
http://travelersvideo.com/hv20.jpg This weekend, I'll experiment with turning down the camera's internal sharpening. However, if it can't be eliminated or, at least, significantly mitigated, I'll probably return the camera. |
November 1st, 2007, 10:38 PM | #15 |
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Looks like good 4:2:0 HDV 1440x1080 HDV footage to me. What do I mean? I see MPEG compression artifacts, and interlace artifacts, and that be normal. This IS an HDV consumer camera, using the commonly accepted GOP technique to capture pseudo-HD. If you notice that on HDMI input, that's good - you're seeing more detail. From what I've read, it'll all get worse with a Sony HC7 as it sharpens the image even more.
I see nothing wrong. However, if you're not happy with a purchase, return it if that will let you feel better. Be prepared to fork out more dough for a higher end camera, or wait a year or more for a camera to offer more TVL/ph at a similar price point to still get good value on your dollar.
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