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macgregor
05-06-2005, 03:58 PM
I found confusing information about frame rates of this camera.

Will the PAL JVC ProHD record on 720p at 50 or 60 frames per second?

Has anyone checked that at NAB?

thnks

thisiswells
05-06-2005, 04:05 PM
Yes.

macgregor
05-06-2005, 04:28 PM
I think it cannot record on the tape at 60 fps, only outputing it.

By the way:
How long does a tape last in 720p and is it a standard mini-dv tape?

Barry_Green
05-06-2005, 04:28 PM
No it will not. It will record at 25 or 30 frames per second.

It has no capability to record 50 or 60.

It can gather images at 50 or 60 fps, and you can view them on a monitor hooked up to the component outputs, but you cannot record 50 or 60 frames per second.

Barry_Green
05-06-2005, 04:29 PM
It uses standard DV tapes, and they last for an hour.

redindian
05-06-2005, 05:17 PM
No it will not. It will record at 25 or 30 frames per second.

It has no capability to record 50 or 60.

It can gather images at 50 or 60 fps, and you can view them on a monitor hooked up to the component outputs, but you cannot record 50 or 60 frames per second.


so what do they do with it ? I read the brochure where it says 720/60p "live output" - can u translate it ?

If we can see it, cant we record it ?

Barry_Green
05-06-2005, 05:31 PM
You can see it, you cannot record it.

It only allows recording 24p or 30p to tape.

For the 60p, they suggest you could record it uncompressed (which, of course, would require a computer, an HD-SDI capture card, and a RAID of hard disks that could support 166 megabytes per second, plus enough storage, because 1 gigabyte goes by in about six seconds).

In other words, it's not practical for anything, really, other than live switching in a studio environment. For recording, it's best to think of the JVC as 24p/30p only.

And, as has been said many times, I think it's a very, very big mistake, because it means there's no provision to record the "reality" look... but hey, it is what it is.

thisiswells
05-06-2005, 05:52 PM
so what do they do with it ? I read the brochure where it says 720/60p "live output" - can u translate it ?
You can output it to a HD 720p60 monitor or you can record it into a computer. That's it.


If we can see it, cant we record it ?
JVC used an el-cheapo MPEG encoder in the HD100 camcorder and it cannot encode 60p to tape.
It can output the data from the chips at 60p, pre MPEG encoding, but it cannot encode 60p and
it cannot record 60p to a tape. Period. It can record 24p or 30p to tape.

thisiswells
05-06-2005, 05:54 PM
Srry for double the info, Barry. CableModem down for last half hour. . .

macgregor
05-06-2005, 06:32 PM
I read this:

720p/24
720p/25
720p/30

576p/50
576p/25
576i/50


Does this mean it can record 50 complete images at PAL resolution? IN what format (mpeg2)? I donŽt get it. That would give a good slow motion in SD definition, isnŽit?

thisiswells
05-06-2005, 06:43 PM
While I can't speak for a PAL HD100 since I have never touched one, the NTSC version will not
record 60p to tape because of a cheap MPEG encoder JVC chose to use. It's only "fast" enough
to encode 30p or 24p and record that to tape.

PAL is likely 25p or 50i to tape. 50i is like 25 half-images per second. Hard to explain...
Definitely not the same as 50p... though you might have a point about SD slowmotion...
the "look" would be like the horizontal resolution of (imaginary) 360p50, but the full
vertical resolution of 720p50.. That's pretty much useless in my book.

Get an HVX200 if you want slo-mo.

Barry_Green
05-07-2005, 12:00 AM
Interesting -- 576p/50...

Well, the question you ask is a good one -- what does it use to record that signal? I don't know the definitive answer, but I can make a pretty good guess based on their prior camera. The JVC HD1 and HD10 had three modes: 720p/30, 480p/60, and DV. The 480p mode was indeed 60 full progressive frames per second, recorded in MPEG-2.

So, presumably, the new camera is using the same MPEG encoder, and would have the same capability -- standard def at 60p (or 50P in PAL territories), standard DV at 50i (or 60i), and then high-def at either 720/24p, 720/30p, or 720/25p.

Jonathan Smiles
05-15-2005, 05:48 AM
Hi All,

The camera head can output 720p 50p and 720p 60p (59.94) as analogue HD component, which you can convert to HD-SDI and record on a suitable computer, AJA and Blackmagic Design have suitable solutions.

To tape it records as MPEG-2 4:2:0 720p 30p (29.97), 25p.

Special cases:
24p to HDV tape , recorded as 23.976fps with repeat field flags (soft 3:2 pulldown) which gives a 29.97fps compatible stream. Your NLE (FCP with Lumiere HD) can strip flags and create a true 23.976fps file for editing. No bandwidth is wasted on storing duplicate frames.

E models for 50Hz areas "PAL" it also does 576p 50p to HDV tape , storing 50 720x576 progressive frames as MPEG-2.

For the 60Hz "NTSC" areas its 480p 60p to HDV tape, storing 60 720x480 images as MPEG-2.

xray
05-22-2005, 02:11 AM
To tape it records as MPEG-2 4:2:0 720p 30p (29.97), 25p.

E models for 50Hz areas "PAL" it also does 576p 50p to HDV tape , storing 50 720x576 progressive frames as MPEG-2.


Brilliant, all (almost all) we need is here. PAL signal with 50 progressive frames. Now I want PCM audio.

xray
05-22-2005, 02:39 AM
So, presumably, the new camera is using the same MPEG encoder, and would have the same capability -- standard def at 60p (or 50P in PAL territories), standard DV at 50i (or 60i), and then high-def at either 720/24p, 720/30p, or 720/25p.

As I understand it, it is not the same MPEG encoder, it is a new design.