first of all... a cable is simply a piece or pieces of wire that transfer a signal almost at the speed of light. Typical cable problems have to do with noise [rejection] or lack thereof. Be sure you are not looping your power cords in tight circles & then running your signal cables right by them. As far as the weird change such as the slow fading or slow illuminating of certain parts of the picture... I would think that would be either your TV/DVD player & how they process the information on one/both ends. also... if you are concerned about picture quality to the point where you are buying new cables... go ahead & do it right & get equipment that supports component video or even DVI/HDMI.
I went and got an S-video cable from Big Lots for $3.99. They look nice, with 24K gold contacts, dual shield (one braided), copper conductor, strain relief of the cable, etc.
I've tested it and compared to composite. I am disappointed. I see no improvement. I used several DVD's. There are two differences between the two setups. One the composite looks brighter a bit. S-video looked a bit darker and it does not seem to be because the colors are more saturated (Colors look like for the composite). No difference in sharpness of the image between the two either.
The other difference: I used wide screen DVD's. For S-video, when the movie switches from a bright scene to something with less light (or vice-versa) the top and bottom black bars change brightness from a dark gray to black. Or if the image changes from dark to something bright with more light then the bars change from black to something a bit lighter (a dark gray). Now this change happens with the composite, too. The problem is that with the S-video is more pronounced, and moreover it takes longer (like .5 seconds). It's like in slow motion. The scene of the movie has already changed its brightness but these bars are still in the process for another .5 second or so. With the composite it happens almost instantaneously. This is very annoying with the S-video.
Any expert can say if the S-video cable is the problem or is my TV/DVD player? I have a 32" RCA TV (late '90s model) and a Cyberhome CH-DVD 500 DVD player. Thanks.