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Old 24th July 2016, 23:47   #2  |  Link
johnmeyer
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Join Date: Feb 2002
Location: California
Posts: 2,691
First of all, laserdisc is simply analog NTSC video, so whatever techniques you have used for OTA SD captures and VHS/Beta/8mm analog video will also apply to laserdisc.

I still do laserdisc transfers, and am returning one today to a client. Here are the issues I have had to deal with in the past:

1. Sparkle. Laserdiscs often had white "sparkles," similar the white dropouts you get with VHS tape, but more circular. Noise filters or dust/spot removers work best.

2. Levels. Pay particular attention to your histogram or scopes and make sure the levels are correct. Laserdiscs always seem to be a little low on contrast, at least with my transfer technique.

3. Audio. You said that the transfer was done with high-end equipment. The S-Video output actually may be worse than composite. I remember all sorts of posts about this (in Compuserve forums) twenty years ago. I never totally bought into the arguments, but most of what people said was that, unlike VHS where there is a huge reduction in dot crawl and other composite artifacts, such was not the case with laserdisc. However, I'm sure your transfer is fine, and you shouldn't worry about it. The only real advantage to "high end" laserdisc players is that the later generation were able to extract the AC-3 audio, if the laserdisc had it. Most of the early ones did not, and even late in the laserdisc life cycle, many still did not. However, if yours did, hopefully you will have access to the better audio. Whether they were able to tap into the AC-3 output or not, they definitely should have used the digital rather than the analog channel. The differences are not as great as those between VHS linear and Hi-Fi audio, but they are still pretty substantial.

4. Sharpening. I have never felt that sharpening for VHS/Beta/8mm produce acceptable results, but if you have a really good laserdisc transfer, you might want to experiment with a little sharpening.

5. Noise. The noise on a laserdisc is usually much less than what you get from VHS, so you shouldn't need to do too much denoising. I usually use a scaled back version of my MDegrain denoising, although I think people here may be able to suggest a better option.

6. IVTC. The last two laserdiscs I did were both old sports films, so they needed IVTC. The client is really, really sharp, and he caught some pretty significant errors in the IVTC that I had missed. The problems were that I used the default TFM/TDecimate settings. What I found is that the matching was failing quite a bit, and I then looked back at my engineering notebook and discovered that the cthresh setting can make a HUGE difference in the outcome. In my case, setting cthresh=255 fixed all problems. I suggest you look into this and play around with the setting and see if you can spot places where the IVTC fails. What you will see when it fails is what looks like a dropped frame, i.e., the motion will jerk forward too far from one frame to the next, but only once in a great while.

I've got to leave now, but if you have specific questions, post again. Also, if you have some video to post, I'll take a look at it.

Others will have to chime in with suggestions about up-resn'g, although there are literally dozens of threads about that very subject, so you'll probably get more complete answers by just doing some searching.

Last edited by johnmeyer; 26th July 2016 at 17:08. Reason: typo
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