Composite to S-Video Conversion

Discussion in 'Home Theater Projects' started by Bart, Sep 25, 2003.

  1. Bart

    Bart Stunt Coordinator

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    This might be a common question, but I could not find anything by searching the forum. I want to connect all of my components via S-Video, but my VCR only has composite outputs. Is there an adapter I can buy that will convert from composite video to S-Video? I realize I will not have a true S-Video connection from the VCR, but all I care about is that my receiver can switch all the video sources on S-Video. If such adapters exists, are they effective? Also, where would I be able to find one? Would they be stocked in an electronics store, or do I have to resort to the web. I use the term "resort" because I live in Canada and ordering from US websites is sometimes difficult (and expensive). I would appreciate any help you could provide.

    Bart
     
  2. Andrew Pratt

    Andrew Pratt Producer

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    Bart Radio Shack has such as device. Its a small adapter about the size of your thumb that has an S-video connector on one end and an RCA on the other. I have one running on mv VCR to do exactly what you want and they're under $20.
     
  3. Brian L

    Brian L Cinematographer

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    Andrew,

    How do these work? I assume that they are just passive devices?

    I have a very specific application for such a converter, and am curious if its the real deal. I would be interested to learn how they compare to a real s-vid connection.

    BGL
     
  4. ChuckSolo

    ChuckSolo Screenwriter

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    According to the package it is supposed to do a real upconversion from composite to S-Video. I have a VCR hooked to the S-Video input on my bedroom TV via one of these Radio Shack converters. It seems to work ok, but I didn't get the dramatic improvement in picture quality I thought I would. I would say the picture improved about 10% over normal composite. Curiously, when I watch TV via the VCR's tuner, it seems to work a lot better than when I watch a tape. There is definately an improvement in the picture as opposed to when I am watching TV using the Tv's native tuner via the RF cable connector.
     
  5. Bob McElfresh

    Bob McElfresh Producer

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    The $20 radio shack converter WILL do the job.

    But the quality is not great and not recommended for serious video use. It works fine for the occasional VCR use, or so the kids can watch that warn Vegi Tales tape.

    Background:

    Your television has a circuit called a "Comb Filter". It does 1 thing: convert composite to SVideo. It is nearly the most expensive circuit in your television. Televisions used to be rated on how good/poor this circuit was. To make a good one takes very pure and high-quality components, and some good instrumentation to tune and adjust them.

    The $20 Radio Shack converter will bypass your television comb-filter. Likely, the picture quality will not be nearly as good as feeding composite video straight to the TV.

    But it does make using the system a lot easier if every device provides SVideo to the receiver.
     
  6. Bart

    Bart Stunt Coordinator

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    Thanks everyone for the replies. I am not looking for quality here (at least not when using the VCR as a source), just the ability to switch everything on S-Video, so the $20 Radio Shack converter will do just fine.

    Bart
     
  7. Mark Murphy

    Mark Murphy Supporting Actor

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    I had the same dilemma and grabbed an adapter on ebay for $8. The radio shack adapter is $20. The adapter dld the trick, one less cable to run.
     
  8. Andrew Pratt

    Andrew Pratt Producer

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    Bob's correct in that you will not see any improvement in video..and in fact it might get worse but given its VHS to begin with I don't expect much anyway[​IMG]
     
  9. Matthew_V

    Matthew_V Stunt Coordinator

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    I´m glad I found this thread. It was the first time I had come across someone saying that there might actually be a (slight) degradation using one of these converters.

    My primary reason for replying to this thread was to ask about the difference between the Radioshack converter mentioned and this converter from partsexpress (part number 180-141). Why is there such a big difference in price ?

    Here is what would be my potential application for this converter. I have a vcr and Cox cable that I would like to connect to the input on the dvd recorder using a switch box (the switch box has composite and s-video inputs and output). The cable converter box has composite and s-video outputs. So, if I connected the the cable converter box to the switch box via s-video, then I would need one of these converters. But if, like one of the posters said, I am going to experience some video degradation using the converter for a vcr that I plan to use regularly for vcr-->dvd recorder recording, then I guess I should just use composite to connect to the switch box.
    Also, I wasn´t sure if using s-video for connecting the cable converter box to the switch box would be that big of a deal for when I am recording from cable to the dvd recorder. I compared the Cox cable using s-video versus composite and noticed just a *slight* improvement in picture quality.

    Thank you in advance!
     
  10. ChristopherDAC

    ChristopherDAC Producer

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    You say "cable convertor box". If this is standard CATV, then there will be an improvment in video quality using its S-video out if and only if the chroma filter circuit in the cable box is better than that in your TV, since the video is transmitted as a standard RF composite signal. If it is digital cable or sattellite, the video is transmitted as a component signal and therefore using the S connection will avoid several unneccessary stages of signal processing. VHS is a "colour-under" format, which means that you should always use an S-video connection if one is provided on the back of your deck; if none is provided, it is best to make the connection purely composite and not use one of these adaptors. This is particularly true since the comb filters in DVD recorders tend, in geneal, to be very good indeed.
     
  11. Allan Jayne

    Allan Jayne Cinematographer

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    >>> ... my potential application ...

    If you are feeding cable or satellite TV including digital into a DVD recorder it is likely that some channels (still analog) will record better via composite to the DVD recorder's likely better comb filter while the digital channels will always record better with S-video (or component video) connections skipping all comb filters.

    Video hints:
    http://members.aol.com/ajaynejr/vidcomb.htm
     
  12. Matthew_V

    Matthew_V Stunt Coordinator

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    I am very appreciative to the two of you for taking the time to both help me and provide detailed responses. I am at a beginner's level of understanding on all this and your replies were worded in a way that was easy to understand. And that is a fantastic link -- I'll save a copy of it.

    The cable service we're receiving from Cox is a notch down from digital service -- it's "classic cable". The cable converter box is made by Scientific Atlanta. I *believe* that there is a different type of converter box that Cox supplies to the customers with digital service.

    Also, I did a comparison test of the cable box connected to the tv via composite versus s-video, and the results confirm what you said -- the difference was so very tiny that it wouldn't be worth the expense of buying another s-video cable to connect the box to the switch box (the vcr will also be connected to the switch box) and then another s-video cable to connect the switch box to the dvd recorder.

    And the vcr is a several year old non-s-video Sony model.

    And you're right about the quality of the dvd recording (JVC DR-M10) from vhs and cable via composite -- At the right DVD recording speed I was stunned at the improvement in picture quality.
     

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