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GrofLuigi · 25th January 2010, 18:26

Hi, I found this thread late and most of the things I would have wanted to say are already covered by other posters (and I agree with almost all of the responses), so I would like just to emphasize some points which I feel might be lost in the discussion, and (in my opinion and experience) are important:

1. As said, I would give up on USB capturing devices, since they mostly have poor quality and even worse A/V sync problems (usually).

2. The source of audio async is most likely the frequency drift of the audio cards' crystal oscilator, which varies slightly with time (48008 Hz, which I think it's just an average at the end, but it varies all the time). At the time I (and maybe others) were hunting for cards that didn't have this drift, but never could find one below the highest-end (most expensive) cards. But there's no need to, resampling audio is the way to go. No matter how much of a perfectionist one is (I am one too - up to a reasonable limit

), these few Hertz (or tens of, even hundreds of them) will never be noticeable. I am not sure how this drift is translated into the resulting audio when resampling, but I think it's not the frequency of the tone that's varied, but the sampling rate - you end up with few milliseconds of (very slightly) decreased "resolution" of your audio - so what? VHS is up to 10 KHz anyway (as far as I remember; just like SVHS's Hi-Fi audio track was 16 KHz).

3. Also, I suspect another capture card might not be needed at all. What I would do, first, is to determine the chip of the Pinnacle card and maybe hunt for a better driver (if it's BT8xx, it's no contest - BtWinCap is the way to go, maybe with Bt Tweaker).

4. If all else fails, I concur that the most pain-free solution would be to (buy)/(buy used)/(borrow from a friend)/(rent) a DV camera with pass-through (some of them don't have it). DV is way more than enough for VHS. I've heard both good and bad thing about Canopus cards and the like, and I suspect such a solution would be overkill. A DVD recorder might do the job too, but I personally would not use it because of limited re-editing and/or filtering possibilities. But again, it might be good enough for some uses, even with recompression.

5. If VirtualDub crashed on you, next time when you enter capture mode, hold SHIFT and it will not select a capture driver.

I had more thoughts, but I have to go now...

GL

25th January 2010, 18:26	#23 \| Link
GrofLuigi Member of a Library Join Date: Oct 2002 Posts: 463	Hi, I found this thread late and most of the things I would have wanted to say are already covered by other posters (and I agree with almost all of the responses), so I would like just to emphasize some points which I feel might be lost in the discussion, and (in my opinion and experience) are important: 1. As said, I would give up on USB capturing devices, since they mostly have poor quality and even worse A/V sync problems (usually). 2. The source of audio async is most likely the frequency drift of the audio cards' crystal oscilator, which varies slightly with time (48008 Hz, which I think it's just an average at the end, but it varies all the time). At the time I (and maybe others) were hunting for cards that didn't have this drift, but never could find one below the highest-end (most expensive) cards. But there's no need to, resampling audio is the way to go. No matter how much of a perfectionist one is (I am one too - up to a reasonable limit ), these few Hertz (or tens of, even hundreds of them) will never be noticeable. I am not sure how this drift is translated into the resulting audio when resampling, but I think it's not the frequency of the tone that's varied, but the sampling rate - you end up with few milliseconds of (very slightly) decreased "resolution" of your audio - so what? VHS is up to 10 KHz anyway (as far as I remember; just like SVHS's Hi-Fi audio track was 16 KHz). 3. Also, I suspect another capture card might not be needed at all. What I would do, first, is to determine the chip of the Pinnacle card and maybe hunt for a better driver (if it's BT8xx, it's no contest - BtWinCap is the way to go, maybe with Bt Tweaker). 4. If all else fails, I concur that the most pain-free solution would be to (buy)/(buy used)/(borrow from a friend)/(rent) a DV camera with pass-through (some of them don't have it). DV is way more than enough for VHS. I've heard both good and bad thing about Canopus cards and the like, and I suspect such a solution would be overkill. A DVD recorder might do the job too, but I personally would not use it because of limited re-editing and/or filtering possibilities. But again, it might be good enough for some uses, even with recompression. 5. If VirtualDub crashed on you, next time when you enter capture mode, hold SHIFT and it will not select a capture driver. I had more thoughts, but I have to go now... GL