With any analogue transfer the key is the playback device. Most home VHS players are pretty poor in quality. Try and find one with:
- 4+ heads (90% of home units only have 2, professional systems can have up to 8).
- A good automatic tracking adjustment system.
- A 'HiFi' audio system.
- The same format as the tapes you intended to transfer. Some do both PAL, SECAM and NTSC, I cannot say if the quality is as good as format specific ones.
- S-Video output (if your capture unit supports it). It is significantly better than using RCA cables and less fuss (2 vs 6 things to plug in).
Once you manage to find a good one you will need to make sure that...
- The player's heads are clean (you can get VHS cleaning tapes).
- The cables from the VHS player to the capture unit are of good quality (preferably Gold), connected securely with no harsh bends and no longer than they need to be (signal degrades over distance).
- The power source for the VHS player and computer (and anything connected to either) is properly grounded and doesn't spike heavily.
- The VHS player is properly set up (doesn't display a PLAY message at the start, doesn't filter the video unnecessarily, doesn't mess with the colour balance etc...).
Then take the source VHS tape, check that...
- It doesn't have any twisted, stretched or break-on parts. You can iron out small twists (pull the tape out, and iron the underside). Really damaged segments should be carefully cut out and the tape glued back together (superglue worked for me).
- The plastic cassette is in good condition it's reels turn okay. To check this move both in the same direction at once (pulling only one round will stretch the tape!.) Jamming is what you are watching out for - it is normal for the movement to be 'clunky'.
- Isn't greasy/dirty. Carefully wipe anything off with some lens cleaner and a soft cloth. VHS tape cleaners do exist - can't say I have ever used one.
Once all this is done you are almost much ready to begin the transfer. Remember...
- Make sure that the recording program you are using has the video output set to the highest possible quality. If it allows you to select a lossless format, great. If its limited to MPEG-2/4 go for the highest allowable bitrate. For home products the hardware encoder is not going to be great. Also it won't know what bitrate is needed for the output video to fit on the target medium (i.e. DVD-R). Once the transfer is complete and any editing is done re-encode using a good quality multi-pass variable bitrate encoder (giving a perfectly sized output with the data optimally distributed).
- Make sure the computer is clean & the drives de-fragmented
- When recording don't do anything to resource-heavy on the computer.
- Don't move or knock the VHS player.