Posts: 2110
From: Loganville, Georgia, USA
Registered: Jun 2003
posted April 30, 2005 03:23 PM
Okay, here we go. I found this DVD player online that plays any DVD anywhere in the world. 110v or 220v. It will convert NTSC to PAL or PAL to NTSC. If I used a 25fps crystal sync(maybe Pedro's) with this unit, could I play an NTSC DVD conveted to PAL through the crstal lock sync and into a GS-1200 for recording a new sound track?
posted April 30, 2005 08:01 PM
My opinion? It just might work.
Really, even after thinking it through I can't think of any reason why it shouldn't - although it's interesting to note that while the effective frame rate of film on NTSC DVDs is 23.976fps, on PAL DVDs it's exactly 25.000fps, so when playing NTSC DVDs on a PAL TV, this player would have to slightly accelerate the sound in order to stay in sync. Which is exactly what you'd want it to do, in this case. So yes - I think it'll work.
I take it those of you with GS1200s in PAL-land re-record soundtracks at a quartz-controlled 25fps, but then screen your feature at the normal 24fps afterward which will slightly slow down the sound to its correct pitch again? Right?
-------------------- Call me Phoenix. *dusts off the ashes*
posted April 30, 2005 10:21 PM
Dan, remember I spoke about the effective frame rate for film stored on NTSC video. You're correct in that the actual NTSC video frame rate is 29.970fps (or 59.940 interlaced fields per second) but film is of course telecined to match the video.
The interesting part is: NTSC TV used to be a flat 30fps, back in the days of black-and-white - it was synced to the 60Hz AC mains frequency - but when they added color to the mix, they found that the chrominance (color) signal caused massive interference with the luminance (brightness) signal, and in order to solve that problem and make the two frequency carriers "jibe" together, the horizontal scan line frequency (and thus the frame rate) had to be adjusted. As a result, NTSC TVs no longer derive their sync from the AC power but from the video signal itself. There's more to it but it would go beyond the scope of this forum.
-------------------- Call me Phoenix. *dusts off the ashes*
posted May 03, 2005 02:36 AM
Bear in mind we use VHS, Laser Disc and DVD's here in the UK that convert NTSC to PAL but sync' doesn't work. The ESS Pulse goes hunting but can't find a signal to lock onto. It all comes down to the format (NTSC or PAL) the video was originally mastered in.
In summary, it doesn't work.
-------------------- British Film Collectors Convention home page www.bfcc.biz. The site is for the whole of the film collecting hobby and not just the BFCC.
posted May 03, 2005 03:49 AM
As has been said many times the ESS will only work with NTSC titles if the Sync Box gives out a 23.976 pulse. Pedro may now have an answer to this problem which could result in a box which will have a fully programable output giving any pulse from 16 to 25. It would be a case of setting the value required on a built in digital readout. In other words he's looking at possibly building a box round a fully adjustable oscillator. Lets be patient and see. Most so called machines which I have ever seen which supposedly convert NTSC to PAL convert it to what is called PAL 60. I dont know quite how this works but it would be interesting to see if it down converts to the 25 cycles UK frame rate.
Kev.
-------------------- GS1200 Xenon with Elmo 1.0...great combo along with a 16-CL Xenon for that super bright white light.
posted May 03, 2005 09:25 PM
Yup... PAL-60 is actually NTSC, but with the color portion of the video signal encoded according to PAL specs, rather than NTSC's. However you still have a 525-line, 60Hz signal for which you need a PAL-60 capable TV to display it - that is, a TV that can sync to the 60Hz refresh rate of a PAL-60 signal but doesn't have to know anything about NTSC color encoding. (PAL itself is a 625-line, 50Hz signal).
Now the thing is that that international DVD player which Dan found WILL playback NTSC DVDs with true PAL output. That means internal conversion from 60fps to 50fps, scanline interpolation to go from 525 lines to 625... and presumably a slight acceleration in sound playback because what was meant to be played at 23.976fps now comes out at 25fps. The same applies when going the other way - playing PAL DVDs but with true NTSC output.
That's the neat thing about that player - you do NOT need a multiformat-capable TV to go with it (like you do with typical multiformat VCRs) because it performs true NTSC/PAL conversion on the fly, the same process that photo/video shops use when you give them a videotape to make a converted copy of.
-------------------- Call me Phoenix. *dusts off the ashes*