1. Join Now

    AVForums.com uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Poor PQ from RGB Scart - why?

Discussion in 'Cables & Switches' started by theo cupier, Jan 25, 2005.

  1. theo cupier

    theo cupier
    Active Member

    Joined:
    Sep 18, 2004
    Messages:
    1,649
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    63
    Location:
    Amersham, Bucks
    Ratings:
    +113
    I have my DVD player set to output RGB. It's doing so via a reasonable quality Scart lead (Monster Video 1, I think) into a Vivicano automatic scart switch.

    The DVD player is plugged in to AV4 on the switch box - because AV1 (the only socket labelled RGB on the box) is duff.

    The built-in Scart out lead from the switch to the AV1 Scart on the TV is not great quality.

    I noticed yesterday when I paused Star Wars II during the end credits that I was getting quite a fuzzy picture. The light blue text was blurred - not exactly bleeding into the black background, but not sharp.

    It remained at exactly the same (lack of) sharpness when I set the DVD to output composite instead of RGB.

    When I set the DVD to output S-video, the colour disappeared to leave a black & white picture but it was VERY sharp. I would have expected the RGB signal to be as sharp as the S-video signal.

    So, my question is: why is my picture blurred when the DVD is outputting RGB?

    Is it because I am (probably) not using an RGB-compatible socket on the Scart switch box? Would this down-convert the signal to composite?
    Do I just have unnatural expectations of PQ?
    Might it be the quality of the TV set itself?

    Any suggestions welcome.

    Thanks

    Theo
     
  2. nwgarratt

    nwgarratt
    Distinguished Member

    Joined:
    May 5, 2002
    Messages:
    26,393
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    166
    Ratings:
    +2,858
    I think you have answered your own question. It looks like the AV1 of the scart box is only RGB. As you are using AV4, the picture is converted to composite. It doesn't matter if you set it to RGB in the player. It is still composite.

    One way to check the cable is ok in RGB, is put the scart cable directly from the player to the TV. The TV scart has to be able to accept RGB as well.
     
  3. theo cupier

    theo cupier
    Active Member

    Joined:
    Sep 18, 2004
    Messages:
    1,649
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    63
    Location:
    Amersham, Bucks
    Ratings:
    +113
    nwgarratt

    Thanks for that. I didn't know what the switch box would do if I put RGB into a non-RGB socket. I had sort of expected it to do something more dramatic (like be only black & white as with S-Video). But if it is capable of down converting then that almost certainly explains it (cheap TV and rubbish scart lead notwithstanding).

    I was going to get round to trying the direct connection, but since all my leads & sockets are tricky to get to I wanted to see if that was where the problem lay beforehand.

    Looks like I need to pick up a new Scart Switcher, then... Might try the new vivicano 5-way which John Lewis and Richer Sounds are selling, since I've tried the Monster 3-way and found 2 of them not to work.
     
  4. MarkE19

    MarkE19
    Moderator

    Joined:
    Aug 10, 2002
    Messages:
    17,129
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    166
    Location:
    Rainham Essex
    Ratings:
    +2,392
    RGB is not downconverted to composite on a non RGB scart socket. The picture from an RGB scart is 'RGBs' where the 's' is the sync signal sent on the composite pin of the scart. If AV4 on the switch box is not wired for RGB then all you are getting through it is the composite signal with the RGB being left behind.

    Mark.
     
  5. nwgarratt

    nwgarratt
    Distinguished Member

    Joined:
    May 5, 2002
    Messages:
    26,393
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    166
    Ratings:
    +2,858
    That was what I was trying to say. It still means composite goes into the scart box.

    theo cupier,

    I use a Joytech AV scart box. It has four RGB inputs as well as digital optical sound, analogue stereo and S Video and compsite video. It comes in silver and black. It also has a remote.

    http://www.play.com/play247.asp?page=title&r=ELEC&title=171031
     
  6. theo cupier

    theo cupier
    Active Member

    Joined:
    Sep 18, 2004
    Messages:
    1,649
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    63
    Location:
    Amersham, Bucks
    Ratings:
    +113
    nwgarratt & MarkE19
    Thanks both. the long & short of it is that the signal goes in to the scart switch 'good' and comes out 'less good' since it's not using an RGB socket. this I understand.

    I think the Joytech box might be a little overkill since I don't need that many optical inputs etc. But on the other hand why aim low! Presumably I would also need to buy a Scart lead for the output from the switch box to the TV, or is one included?

    I notice it's manual switching - are these better than the auto-switch boxes? Reason I ask is that the box needs to be tucked out of the way to stop my kids' inquisitive hands from playing with it, so auto-switching is rather an advantage. If it improves the signal then I would need to give this some careful thought...

    Cheers again.

    Theo
     
  7. nwgarratt

    nwgarratt
    Distinguished Member

    Joined:
    May 5, 2002
    Messages:
    26,393
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    166
    Ratings:
    +2,858

Share This Page

Loading...