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-   -   All this for nothin'! (https://www.dvinfo.net/forum/jvc-gr-hd1u-jy-hd10u/21715-all-nothin.html)

Thomas Ferlauto February 21st, 2004 11:57 AM

All this for nothin'!
 
I have to commend you guys, the intelligence on this board is great. I have been lurking here for sometime learning how to move into HD. Yesterday I received my JY-HD10 at 2:00 p.m. By 6:00 p.m. I had shot sample footage, imported it into my mac with DVHSCap, demuxed it with mpgtxwrap, converted the video to Pixlet with mm2c, converted the audio with iTunes and iMovie, rejoined the audio and video in Premiere 6.5 (I have FCE, but not FCP), made some sample edits, output to 1280x720 pixlet, then converted back to .ts with Paul's droplet. The process is complicated but it all works!!!

However, I'm returning the camera. It does not work right. How can they sell a camcorder with a rotating grip that cannot under any circumstances ever be used in hand-held situations? The pictures were great (I didn't even have any complaints about the color) when using a tripod without a pan or tilt on stationary objects, but introduce any motion whatsoever, and the image quality drops off dramatically -- and no, it is not a film look. I imagine that it can create acceptable images if always used on a tripod, with slow camera moves and no zooms, but I expect more from a $2,700 camera.

The problem is the frame rate. I tested the 480p/60 mode and it improve the judder or jitter problem, but I bought this camera for its HiDef capability -- which does not work! I guess I'll have to wait until the 1080i versions come out. The 60 fields per second should make a usable camcorder. The moral of the story is: 720p/60 yes, 1080i/30 yes, 720p/30 no!

Once again, you guys were great. I learned everything I needed to know how to edit with this camera.

Sanjin Jukic February 21st, 2004 01:36 PM

XportHD ic coming....
 
Thomas,

This camcorder is more like an older film cameras, doesn't allow to much movements and need carefully chosen light conditions. About transferring your edited movie in m2t files to your "beloved" JVC camcorder or JVC DVHS deck you should look for Heuris (http://www.heuris.com/) solution HD Indie Toolkit and its app/QT-plugin XportHD that is coming up at the end of this month...

And if you really like a film-look like you should try out Apple Shake Compositing Tool and its filters for film grain look in many diverse EASTMAN KODAK granular customizable presets,


Sanjin

Les Dit February 21st, 2004 02:29 PM

How do those people making feature films get away with 24 fps?
Are you doing some extreme sports stuff, or ?
-Les

Sanjin Jukic February 21st, 2004 02:42 PM

PAL version helps....
 
Hi,

If you have a PAL version of JVC HDV Camcorder you can achieve P25 shooting mode in HD that is 25 fps and later with Apple Cinema Tools to "kick it of" one frame per second to get a famous 24p...no so bad option...try it out!

Sanjin

Thomas Ferlauto February 21st, 2004 04:04 PM

I know. Film uses 24fps and this camera does 30fps. So, if film looks good, so should this camera, because this camera has an even faster frame rate...

That is not necessarily the case. First, when film is projected, they repeat every frame twice so that there are 48 images per second. Second, and more importantly, with film each of the 24 frames consists of entirely new image material. With the MPEG compression, you get one key frame followed by several frames based on the prior. So, you don't really get 30 real discrete frames per second. you get 5 or 10 frames with the rest interpolated. (I'm not sure about the exact numbers) Anyway, 30fps is a low frame rate. This combined with the MPEG compression leaves you with a camera which is too unforgiving of motion (for a motion picture camera that is).

The 480p/60 looked really good though. I imagine it would make great footage for DVD's, but I want HiDef.

David Newman February 21st, 2004 04:34 PM

Your understanding of MPEG is a litte naive. MPEG is not the issue, as frames are not interpolated as you describe. Note: the 480P60 mode is also MPEG and it has twice as many frames between between keys (I-frames) as the 30P mode (480p60 has a GOP length of 12 vs 720p30 has a GOP of 6 -- the shorter the better for editing.) And you like the 480p60, yet it is has more interlopation (your term). There is nothing wrong with MPEG, given that all digital TV boardcasts and DVD are MPEG (15frame GOPs typically.) Also the analysis of the 48fps film presentation also doesn't hold up as 720p30 is always presented at 60fps on HDTV. So basically, you are simply not used to shooting at 24p or 30p, I understand it is tricky, but it is not a failure of the camera.

Note: 480p60 is bad for DVD creation as you have to discard vertical resolution to make it 60i or discard temporal resolution to make it 30p. 60p can't played from standard DVD. Now 720p30 is a good choice for DVD, the frame rate frame fits and the addition resolution provides oversampling to give the cleanest DVD output. This I highly recommend.

Geoff Pepos February 21st, 2004 06:39 PM

Thomas,

Try a shutter speed of 60 and you'll see much improvement...

(note: 24fps for film cameras is usually shot with a 180 degree shutter which means: 1/48th of a second shutter speed.)

g.

Thomas Ferlauto February 21st, 2004 06:39 PM

I'm not going to argue with an expert. I'm sure there is nothing wrong with the MPEG component of this camera. As I'm sure there is nothing wrong with a low frame rate of 30fps. However, it is my humble opinion that when you put the two together, you have a problem. One or the other by itself is fine, but together, in your image capture device, is a problem.

Les Dit February 21st, 2004 09:21 PM

Perhaps some people are more sensitive to mpeg artifacts than others. I didn't care for the compression used on some of the lower bit rate channels on Direct TV ( The history channel, for one ). The artifacts were objects with a slight amount of motion, like looking out a plane window, and parts of the image just staying static. The oddest one I saw was a news man in his dark suit, his suit stayed static for a while, and his head and neck were moving around in it, like some kind of puppet!
Lord knows how much politics there must be in thier bitrate allocation plans.

Mpeg does motion tracking of pixel groups, and uses redundancy in inter frame spans to just 'move those around', in layman's terms.
I really haven't noticed too many artifacts on the JVC, other than banding in the sky. I use 1/30 or 1/60 second speeds.

-Les

Betsy Moore February 22nd, 2004 12:47 AM

I was thinking the same thing as Geoff. Motion is almost unwatchable at 30 shutter speed but video-like at 60--I wonder if that was the problem. As for the rotator grip, I love the feel of the camera in my hand, it may just take getting used to. You might learn to love it. Maybe play around with it a little more before you return it.

Robert Jackson February 22nd, 2004 02:54 PM

<<<-- Originally posted by Les Dit : How do those people making feature films get away with 24 fps?
Are you doing some extreme sports stuff, or ?
-Les -->>>

I'm in film school right now and I have to say that getting used to shooting at 24 fps after years of working in video production has taken a lot of getting used to. The kind of motion you capture at 24 fps isn't really very dynamic. A lot of the results are terrible. The thing is, once you get used to shooting at 24 fps and get used to how it behaves then you'll start noticing how crappy it behaves in a lot of commercial films. Post-production sound really polishes up most productions and if the sound is coherent most people don't notice too much if the images aren't nearly as coherent. The bottom line (IMO) is that 24 fps is a really crappy frame rate for shooting film. 30p is a little better, but still behaves pretty similarly to 24p. I haven't had the experience, but I'll bet 60p is really nice.

Sanjin Jukic February 22nd, 2004 03:11 PM

read this...
 
maybe to watch on a small screen 60p looks better but a big "silver" screen needs 24p...no compromise!

please read this on the link below (need registration):

http://www.dv.com/features/features_.../2003/wilt1003


Sanjin

Sanjin Jukic February 22nd, 2004 03:17 PM

one example...
 
Richard,

Why 24 fps?


There's a general impression that 24 fps is the One True Frame Rate, and only 24 fps is capable of capturing dramatic material with just the right amount of unreality for storytelling. A slower frame rate is too jerky, but what about a faster one? Sixty fps (okay, it's really 60 fields per second, but the motion is updated 60 times per second whether it's interlaced fields or proscanned frames) is fine for news, and the immediacy of video, but useless for drama. It's too real, too immediate, and it "looks like television, not like film."

more you can read on:

http://www.dv.com/features/features_item.jhtml?LookupId=/xml/feature/2003/wilt1003

Sanjin

Robert Jackson February 22nd, 2004 03:28 PM

Re: read this...
 
<<<-- Originally posted by Sanjin Jukic : maybe to watch on a small screen 60p looks better but a big "silver" screen needs 24p...no compromise!
Sanjin -->>>

Actually, 24 fps was a compromise in the first place. As the author of the article you reference points out, younger audiences don't seem to have nearly as much trouble with 60 fps as older audiences. I'd bet that a lot of that is conditioning. Older audiences have been conditioned to respond to the "24 fps look" through years and years of theatric screenings. Younger audiences are much quicker to adapt to a new way of presenting moving pictures.

I watch a lot of 720p on HD cable that originates from video. It doesn't look like film, but it has a lot of appeal on its own terms. I think that clinging to 24p will fall away when enough people realize what higher frame rates can offer them.

Sanjin Jukic February 22nd, 2004 03:58 PM

maybe
 
Richard,

I must repeat again: it works for a small screen (60p on tv, computer, plasma or all electronic devices using a screen) but in movie theater 60p is too fast (by the way have you any real theatre experience?), for sure it is not about conditioning and it is about a nature and that is a human eye perception and human brain reception (that you mean to envolve conditioning) or maybe, i would say, you were perhaps conditioned to watch 60p, that's it...tv+computer games generation...

think about it once more...

Sanjin


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