View Full Version : RGB looks terrible on my SNES and SNES Jr.
DaddyLongLegs
08-19-2010, 08:44 AM
Hi all. I have the very popular CVS287 to transcode SCART to YUV/Component since I live in the USA and do not have SCART inputs on my TV. I can get my SNES (and my SNES Jr. after I modded it) to display a picture, but the quality stinks. It's way too washed out. I noticed in games where the screen dims (like when you change a scene) it looks great for a millisecond.
I opened up the CVS287 and adjusted all the pots and could not get anything better. I am thinking 75ohms wasn't a good resistor to use for the SNES Jr. (maybe I should go higher to get a darker picture) but that doesn't explain why the original SNES looks terrible too. I know it's not the SCART cable because I literally have 5 of them (one of them is an official Nintendo one which cost me a small fortune) and I know it's not the CVS287 transcoder because I tried two of them. Any help would be really appreciated.
izarate
08-19-2010, 10:19 AM
What if you turn down the brightness on the TV?
DaddyLongLegs
08-19-2010, 12:21 PM
What if you turn down the brightness on the TV?
Doesn't help. Plus I'd hate to have to adjust my TV settings every time like that anyway. Just wondering why everyone gets miraculous results with RGB from their SNES and I don't.
I was thinking of just saying the hell with it and getting a SCART to HDMI converter that I saw. Only problem is I don't like the fact that it upscales to 720p. I already have a standalone upscaler (DVDO Edge) and I want everything native. But I can't figure out for the life of me why RGB looks so crappy on both the original SNES and the SNES Jr. which is supposed to be better.
Increasing the resistors (from 75ohm to maybe 100ohm) would make the picture darker, correct?
You have the wrong cable. There should be a set of 3 capacitors on the r, g, b lines, not resistors. Having 3 resistors would indicate it was designed for a PAL snes.
http://members.optusnet.com.au/eviltim/gamescart/snesntsc.png
I would get one from pcenginesales and ask that they modify it for a US/NTSC snes, or look for one that says its for a pal gamecube (those should have the 3 caps instead as well).
Emuaust
08-19-2010, 05:11 PM
You have a PAL SNES SCART RGB cable and thats your problem, what you need to do is buy a Gamecube RBG Scart cable and you will be fine.
DaddyLongLegs
08-19-2010, 05:21 PM
I'm using the proper SCART cable. The reason I mentioned a 75ohm resistor was because when doing the RGB mod to the SNES Jr., you need to put 75ohm resistors on the R, G, and B lines. Nothing to do with the cable.
izarate
08-19-2010, 06:21 PM
If I recall correctly, the mod mentions that you should use resistors between 75-125 ohms so I guess you could try with 125 Ohms and see what you get.
Increasing the capacitance will also dim the screen, if you want to try a higher amount on the r, g and b lines.
DaddyLongLegs
08-20-2010, 05:15 AM
Just ordered some 125ohm resistors. Hopefully it darkens the picture because I've spent so much money on these SCART cables and SCART to YUV transcoders. Thanks again guys. I'll report back how 125ohms ends up working for me. I'm not too hopeful though because it wouldn't explain why my old-style SNES looks poor on RGB.
Emuaust
08-20-2010, 05:38 AM
it looks poor because you bought a pal scart rgb snes cable, they give a different picture to what would be required to be a "snes ntsc scart" cable and im 100% sure this is your issue due to the lack of a resistor in pal snes cables, it would be much easier to grab a cheap ass PAL gamecube rgb scart cable and use that for your ntsc snes. It will give you the image you desire.
I have personally had this issue before with using your setup and I can go into detail why if you like.
theclaw
08-20-2010, 05:47 AM
ntsc scart cables? huh? I'm sure not aware of any ntsc country, where the average john doe would even know what scart is. let alone go through the trouble to use it in a place with next to zero compatible TVs available.
Obviously the topic creator is someone daring enough to find a way though.
Emuaust
08-20-2010, 06:35 AM
Im trying to dumb it down as much as possible for the topic creator, instead of being a smartass how about contributing something constructive?
Retromangia
08-20-2010, 03:44 PM
ok just to clarify... for SNES scart.... do you need to buy an NTSC Gamecube Scart cable, or a PAL Gamecube Scart cable?
- Retromangia
DaddyLongLegs
08-20-2010, 05:07 PM
I am 100% certain I am using a NTSC SCART cable. It is wired identically to that website with all the SCART schematics.
Emuaust
08-20-2010, 05:13 PM
ok just to clarify... for SNES scart.... do you need to buy an NTSC Gamecube Scart cable, or a PAL Gamecube Scart cable?
- Retromangia
What region is your SNES?
ok just to clarify... for SNES scart.... do you need to buy an NTSC Gamecube Scart cable, or a PAL Gamecube Scart cable?
- Retromangia
There is no such thing as an ntsc gamecube scart cable. The gamecube rgb scart cables on ebay are for PAL gamecubes, which happen to have the same / very similar wiring to what would be required for ntsc snes rgb output. If its specifically advertised for PAL snes, then it probably is designed for that (and only that).
http://members.optusnet.com.au/eviltim/gamescart/gamescart.htm
Just ordered some 125ohm resistors. Hopefully it darkens the picture because I've spent so much money on these SCART cables and SCART to YUV transcoders. Thanks again guys. I'll report back how 125ohms ends up working for me. I'm not too hopeful though because it wouldn't explain why my old-style SNES looks poor on RGB.
Did you try a higher capacitance on the r, g, b lines yet - if they are at 100uf, try 220 (they should be 220, a lot of cheap cables have 100). if they are 220, the next highest up I could find was 470, but those were oversized so you might need to find some online.
DaddyLongLegs
08-21-2010, 10:24 PM
Did you try a higher capacitance on the r, g, b lines yet - if they are at 100uf, try 220 (they should be 220, a lot of cheap cables have 100). if they are 220, the next highest up I could find was 470, but those were oversized so you might need to find some online.
I changed the 75ohm resistors on the R, G, and B lines and success! The picture is 100x better now! It's still a bit too bright, so I am going to go to 125, but at least I now know the root of my problem.
Not sure why the guide calls for 75ohm resistors but maybe that's for people hooking their SNES up to an arcade monitor. For my plasma it definitely looked terrible.