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Tempest
08-26-2009, 04:50 PM
I originally posted this over on AA, but there are probably more Sega CD fans over here that might be able to help.

I have a Sega Genesis model 1 hooked up to a Sega CD and a 32X (yes it also forms Devistator). I was playing Popful Mail all weekend when I noticed something amiss. The graphics and colors appear to be correct, but it would appear that the 'dithering' isn't working correctly. By this I mean I see all the pixels and they don't seem to blend right. For example look at this picture (taken from an emulator I would imagine):

http://4.bp.blogspot.com/_JdoOOej8rx8/SiQE5SjQQfI/AAAAAAAAAdw/5fGEL87eGQs/s400/Popful_Mail_Sega_CD.gif

Notice how the word MuttonHead is in gold and the border around the status bar is all one color and piece? On my TV the gold colored words are hard to read because they're all pixilated and I can see that the border is made up of individual little pixels and not one solid piece. It's like things aren't blending in right for some reason. I also get the problem in the boxes around the character portraits. I might expect this kind of thing with S-Video and older games, but not composite.

For what its worth I'm using an 6 or 7 year old JVC i'Art CRT TV with all the settings at default (the sharpness isn't turned way up or anything). I tried using a model 2 Sega CD, a model 2 Genny, and a Laseractive unit, but I had the same problem.

Has anyone else had this problem? At this point I'm ready to chalk it up to my TV being too large and me sitting too close to it (32" and 3 feet).

Tempest

todesengel
08-26-2009, 04:55 PM
If you have access to another TV try it on that and see if you get the same problem. I don't think it would be the size of the TV because a friend of mine has a 32inch JVC CRT as well and we never had that type of problem with any of the older games on it.

ccovell
08-26-2009, 07:47 PM
Does the coloured text/border have a dithered pattern kind of like this?
http://www.disgruntleddesigner.com/chrisc/gotRGB/screenshots/ng_blu1_comp.jpg

If so, welcome to the world of shitty Genesis composite video. The Genesis is one of the worst out there.

The technical reason is this: Composite encoders generate colours by modulating a video signal at different frequencies (or phases) of a sine wave. Going from black to a certain colour is not so tough, and you hardly notice any distortion (except for the usual composite artifacts). But in that picture of yours, the video signal has to go from encoding the signal as blue, to spinning the phase around to gold (red+green), and the frequency of the colour carrier is not fast enough to change colours instantaneously & without seeing smearing/inteference on-screen.

(More here: http://www.disgruntleddesigner.com/chrisc/gotRGB/screenshots.html )

Tempest
08-26-2009, 09:30 PM
Yeah that's pretty close to what I'm talking about. Damn. Looks like I'll have to deal with it. :)

Tempest

Black_Tiger
08-27-2009, 08:59 PM
If you haven't already, run the video from your 32X. I know it works with cart games...