Ok I will explain myself - In my case disc space is not an issue. Why ? Because I usually record one program at a time on DVD. The DVDs I produce for myself and the companies I deal with are 2 hours or less and my own VHS transfers are usually SP 2 hours. The fact I use a PC with a professional hardware encoder, I get excellent quality at low bit rates compared to consumer encoders, so why would I use lower resolution anyway ? I am not in need of the space or the extra quality since I will get none. Now, where it is efficient to use Half-D1 is, say you are recording material over 2 hours or you want to fit multiple programs on a disc, this is where you need to squeeze as much material in the space given, so you will use half resolution and a lower bitrate, but which will be doubled in efficiency. Example, you have try to fit a 3 hours VHS onto 1 DVD, you would use Half-D1 resolution (352x480) @ 3.5 mbit/s (example)...... given you have half the data to process and half the data being used by the given bitrate, your 3.5 will be just as good as a 7mbit. In case of stand alone DVD recorders you have no choice, anything lower than SP is recorded in Half-D1 automatically, you cannot change that (that's how it works on most consumer dvd recorders and even professional ones). On the PC however, I have the choice to change capture resolution at ANY given bitrate. If you are using a DVD Recorder then the resolution is taken care for you.
I hope it is not too confusing.
What I found was that at the lowest bit rate and 352X240 settings, ALL of the computer solutions were inferior to the standalones!!!. Im my opinion, this lowest bitrate setting pretty much matched the standard tv pictures. Still frame captures do show a quality difference but this difference is unnoticeable to me in day to day viewing.
Don't use still frames as reference - Your brain cancels most of this out during motion anyways.
I would NEVER recommend recording at 352x240, that is the lowest resolution used and if I am not mistaken, it uses MPEG-1 (which is also part of the DVD specs) (only at that resolution). I would not go below 352x480 for VHS. Cable broadcast uses a higher resolution than a typical VHS which is 240lines, so you might want to try and experiment and see whcih is suitable for you.
STILL--I'd like to make some quality recording now for later viewing on High Def tvs. And to do that, my original question stands==ie, recording a high def signal that has been downconverted to standard ntsc makes NO SENSE to me and yet that is what all the vendors are advertising???
I'm looking for a capture card that will sample the high def signal directly to the 720x480 format. I think some solutions <might> do this but the advertising copy just doesn't give that information. Thanks again Greg==I think we are pretty close. ///bobbo.
I am not sure I am understanding you here. The current DVD specifications uses standard definition content only. So for now if you have capturing from a hi-def source you have no choice but to use 720x480. By hi-def source you are talking about high definition right ? I hope you are not confusing with S-VHS,DV, etc...
There are some DVD players that will upconvert a standard definition DVD to allow a better picture on your future (or current) high definition capable TV. It is NOT a replacment for true hi-def but on quality players and sets it can get quite decent results.
You might get away at using low bit rates on your regular TVs, but try viewing those on future large screen TVs and they will look ugly, which is why ultimately you want to use the highest bitrate whenever possible, since on a 3 hour VHS (for example) it is not possible, then using half resolution will allow double the efficiency of the low bit rate you will use. That is the point I was trying to make, but I hope this is not too confusing.