This page (origianlly written before the release of the Doctor Who DVD) shows the vast differences between different VCRs and for serious VHS to DVD, how it is worth investing in quality equipment. I have got a JVC HR-S7965; this has a Digital Noise Reduction/Time Base Corrector within it, so that the picture quality reproduction of VHS tapes is greatly improved. Judge for yourself from the screen shots below (all three were captured using an ADVC-50; see the Video Hardware Set-Up page).
The image used is taken from the BBC's 1991 VHS release of "Genesis of the Daleks"; one of the Tom Baker Doctor Who classics.
The first screen capture is taken from my old Panasonic NV-HD90, bought about 1994. I have been using this for all of my VHS conversions until I bought the JVC and it had been a very reliable machine.
Regards the picture quality, there is a fair amount of Chroma noise (this is the colour that can be seen in the plain areas: in this case particularly the brown area to the right of Davros) and the colours are a bit washed out. However, the detail is fairly good.
View the full size version here
The second screen capture is from a newer Panasonic NV-HV61 which I bought in 2004 - just before DVD recorders became available - and was my "tape the programmes that I don't want to miss" VCR until I bought a DVD Recorder.
The colours are better than in the first screenshot, but the Chroma Noise is far worse. The image is also a little fuzzier than the first; overall a very grainy picture.
View the full size version here
The last screen shot is from my JVC HR-S7965EK. This machine was a little difficult to find (and expensive) but I think that the search was worth it. A very clean playback; the colours are very rich and the detail very clear too. There is a little Chroma Noise, but one has to look very closely to see it.
The chances are that the only place to find a machine in this range would be second hand on ebay.
View the full size version here
Needless to say, the better the original VHS capture, the better the end product, however, even though playing a tape on a VCR with a Digital Noise Reduction/Time Base Corrector greatly improves the playback, there are limitations to what it can achieve. A VHS picture will be much improved, but it will never be DVD quality and if the tape is in a particularly bad state, the JVC may not be able to do much with it either.