My Gen RGB out is not centered (vertical stripe on the right): Is yours too?

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09-11-2010, 11:20 AM
ebo0763

My Gen RGB out is not centered (vertical stripe on the right): Is yours too?

I use a RGB scart out and I noticed that the screen is shifted to the left of about 5% but the most obvious sign is the vertical stripe on the right side. The stripe will be of different color depending on the background.

None of that happen with AV and RF out.

I just want to know if I'm the only one experiencing that. Let me know!
09-11-2010, 11:35 AM
Jorge Nuno

Thats what happens when you use composite video as a sync signal for RGB... The thing is that the composite video is always delayed a bunch of pixels in relation to the RGB signal (because it's derived from it), thats why the cable should be using the /CSync signal instead.

About the stripe, thats all around the display and it's normal, you don't see it on composite/RF because its offscreen, and if the cable was properly made, you wouldn't see it in RGB neither(though it depends of the TV deflection settings).
09-11-2010, 11:42 AM
mick_aka

It's called RGB shift, I have the same issue on my dreamcast :-(
09-11-2010, 11:53 AM
ebo0763

Wow, ok. Is there a way around this? BTW, I use a RGB Scart to component adapter.
09-11-2010, 11:56 AM
Spaced

Does this affect light gun games in any way, or is it true and I "can't hit the broadside of a barn" as I keep getting told
09-11-2010, 11:57 AM
ebo0763

Quote:

Originally Posted by TmEE

most game consoles have RGB shifted to the left... the reason is that it takes time to convert RGB to composhit/s-video and majority of people will use those, so they make RGB start earlier so that composhit.s-video image is centered.

I have made "simple" fix for it, but it breaks 32X compatibility

How do you do that? Any link?
09-11-2010, 12:12 PM
KillerBean2

I'm thinking about building me one of these:

http://playoffline.wordpress.com/cable/rgbshifter/

It should work with all consoles outputting RGB.
09-11-2010, 01:27 PM
Devil N

I simply calibrated my TV through its service menu to make all RGB games perfectly centered. Of course this shifts composite and analog TV signals, but since I hardly ever use those on my CRT TV, I don't really care. I don't think many TVs will allow you to do this though...
09-11-2010, 02:42 PM
ebo0763

Quote:

Originally Posted by Devil N

I simply calibrated my TV through its service menu to make all RGB games perfectly centered. Of course this shifts composite and analog TV signals, but since I hardly ever use those on my CRT TV, I don't really care. I don't think many TVs will allow you to do this though...

Yeah... mine doesn't. :(
09-11-2010, 02:44 PM
TmEE

Here's my sync shifter :

Click for full size

I works ONLY for MD, and it will break 32X compatibility (MD and 32X images get shifted out or roll around).
09-11-2010, 03:34 PM
ebo0763

Quote:

Originally Posted by TmEE

Here's my sync shifter :

I works ONLY for MD, and it will break 32X compatibility (MD and 32X images get shifted out or roll around).

Ho... only for MegaDrive... Thanks anyway!
09-11-2010, 04:34 PM
TmEE

MD/Genny, does not matter, but if the 32X is in the mix it will not work.
09-11-2010, 06:03 PM
ebo0763

Quote:

Originally Posted by TmEE

MD/Genny, does not matter, but if the 32X is in the mix it will not work.

Ok, well that's good. But there are a lots of things I'm not sure about in the schematics: what kind of transistors, what does the 250 kohm graph means, the ends connect where exactly... I know I need a lot of info here but, I hope someone will be willing to help. :confused:

Thanks in advance.
09-12-2010, 08:03 AM
TmEE

Transistors I used were 2SC945 (I love those suckers :P), and 250kohm one is a potentiometer / adjustable resistor / trimmer resistor, which you use to adjust centerness. too much/too little results in rolling+scrolling image. 150kohm is the value I recall using on my old TV.
09-12-2010, 08:16 AM
fr@ser

Quote:

Originally Posted by TmEE

Here's my sync shifter :

Click for full size

I works ONLY for MD, and it will break 32X compatibility (MD and 32X images get shifted out or roll around).

Can you not make the circuit toggle And where is the 1K emitter resistor going to ?
09-12-2010, 11:40 AM
TmEE

1K goes to ground.....

and toggling is of course possible, just cut it off with switches :P
09-12-2010, 08:23 PM
ebo0763

Quote:

Originally Posted by TmEE

Transistors I used were 2SC945 (I love those suckers :P), and 250kohm one is a potentiometer / adjustable resistor / trimmer resistor, which you use to adjust centerness. too much/too little results in rolling+scrolling image. 150kohm is the value I recall using on my old TV.

Allright. Now, did I miss something? ...because I don't see any 150kohm here...
09-12-2010, 09:35 PM
Jorge Nuno

He meant the actual value of the 250k potentiometer (60% of the full scale)
09-16-2010, 08:37 PM
Segasocks

Quote:

Originally Posted by ebo0763

I use a RGB scart out and I noticed that the screen is shifted to the left of about 5% but the most obvious sign is the vertical stripe on the right side. The stripe will be of different color depending on the background.

None of that happen with AV and RF out.

I just want to know if I'm the only one experiencing that. Let me know!

No this is totally usual and can in my experience depend on which tv your using.I did find that when i made my megadrive multi region that running in 60 htz mode did centre my RGB output.