blocky artifacts in some rgb video?

[acem77]

i bought some scart connectors online and modified them to the japanese 21 pin rgb standard for my xrgb2 plus.
i have some problems with some of them. for the most part it seems simple enough to rearrange the pin outs inside the cables.
i have had luck with the snes and dreamcast cables getting nice sharp video with no artifacts.
the sega saturn and sony psx/ps2 cables all seem to share the same problem.
for most games the picture looks good but if you look closer you can tell there are some rapidly moving square artifacts.
games that run in a high resolution and or 60 fps mode really show these ugly square artifacts.
some games i have tried
saturn games dead or alive, vr fighter, fighter mega mix, wide dome in saturn bomber man.
ps1 games turbo prop racing, ridge racer 60 fps bonus disc, ehrgeiz.

i have seen these artifacts in the snes cable before i change the original scart cables wire on the snes side.
they had the (pin 9)composite video as the sync . i switched it to just the (pin 3)composite sync.
now the picture is perfect.

i double checked the saturn scart cable pin out and it is (pin 1) the true composite sync.
so i dont see how i could improve the picture and remove the artifacts.

the psx/ps2 cable i added the lm1881 circuit to pin 6 to filter the true sync signal but the picture still has the artifacts.

i wonder if there is away to get a better picture from those systems?
is the problem i have related to the fact that i am running the rgb to an xrgb2 plus then to the vga port on my hd dlp tv?

i also run my neo-geo, genesis/32x(cdx, and nomad all work)turbo duo+amp, super grafx+amp and super nova to the xrgb2 plus and they all work prefect.
with this many systems working great i cant see it really being a limitation of the xrgb2 plus.

[Aidan]

Which bit of the picture shows the artifacts? The dithering is the most obvious on the background.

[Vertigo]

Erm, yeh, it's called "shit graphics" and is a symptom of 32-bit 3D mate
I have RGB cables for both systems and have no such problems apart from the obvious crappy texturing that you get out of them. It's most likely that now you're not looking at them through blurrydotcrawlvision you can actually now see just how horrid the 3D is from the Saturn and PS/PS2.
By the way, it's hard for us to see "rapidly moving square artifacts" in a still shot but from the clarity of those red edges (best seen where white or black is the next pixel) I'd say you're definitely getting RGB out of the system.

[Endymion]

Looks like a perfectly working Saturn game to me, although you are stretching the aspect ratio by playing it fullscreen in your wide TV so that almost always makes things look a tad weird with games drawn for another ratio. Nothing wrong with the cable or system.

[acem77]

"all of the little squares jitter around almost in an up ward pattern.
i know what dithering is but this is some different. almost every little square in the picture jitters and moves.
i get the same thing if i use composite video as the sync on my xrgb2 plus.
as in my snes example."




all works great now for the saturn and psx/ps2. !!

long story saturn...
i did some testing with a cable i made earlier to let rgb work on my tvs vga port directly.  to do that i had to short/smash  pin8(composite video) to pin4 (+5v) in the saturn side of the cable.
then that let me use the composite video wire as a +5v wire instead since i have no need for composite video.
i had to do this because they left out the wire to give me +5 volts to run the chip in the cable i made to hook up rgb to my tvs vga port. that tested out good no more blocks jittering. so i went back and tied my xrgb one more time and the jittery block disappeared!!!!...


short story saturn
i removed the composite video from the scart cables.
the composite would noise bleed over to the other wire carrying the sync signal intern creating the pixel crawl effect you normally see when just using composite video:P

for the playstation i used pin 5 (S-Video Y ) for my sync signal.
instead of pin 6 (Composite video). this helped big time.
then i had to remove the composite video from the scart cable to get the picture perfect.

moral of the story dont let the composite video signal ride in the same cable when
doing rgb video mods.
maybe if every wire had a separate shield you could but i have no need to so i ll never test that out.


thanks for the help. but...
if you guys thought the 1st pic was a good example of rgb working correctly and it looked good you should all recheck your cabling.
because that 1st pic i posted looks like ass with all those artifacts.
and after seeing the new pic i posted you can really see what it should look like with out the noise induced artifacts.
maybe my head ache can help a few other people.






new rgb to xrgb2 pic all is good!

[NFG]

Wow, that made a hell of a difference.  Nice work.

[Endymion]

Well the thing is, this could easily be something that is only affecting the display you used, my guess is that it's partly due to the upscan. It does look better but there's still some evidence of it there. I notice you removed your pictures with the s-video comparisons, but the s-video still has the hatched pattern across the score/status bars. The RGB/VGA image you just posted is still missing this. You did alleviate your problem somewhat, but not everybody necessarily has problems like that with their setup.

[acem77]

the jittery/crawling pixels are gone.  those artifacts were caused by the composite video running through the cable no ifs ands or buts.
the artifacts are completely gone anything left is the true output from the system.
the svideo and xrgb picture show completely different issue. but can live with that.
i removed them to uncomplicate the real problem of the jittery pixels since it had nothing to do with it.

i have seen enough to know those artifacts are cause by the composite video out put of the system.
i have tired every thing possible to prove it. if you have a xgrb2 and use the composite video from any system as the sync signal or if you even just leave the composite wire in you will see the same thing.
if you are using a xrgb remove anything that has to do with composite video.

[Vertigo]

Yeh, if you had crawling pixels you weren't getting RGB, but it's very hard to tell from that top pic on it's own whether you were getting the right output. Removing composite in order to force RGB or nothing was the right solution, so yeh, well done
Incidentally, I find that the most reliable way to stop a cable or tv having confusion over which to display is to use a SCART switcher box with a RGB on/off switch on, it saves faffing about in TV menus all the time and means that you can just leave RGB switched to on, so that if you're not getting it you get nothing. That's what I use anyway, picture degradation is not noticable for me.

[Endymion]

Dude, chill out. You solved your problem, but did you use this with any other display? Including a PC monitor for that matter? All I am saying is that the problem you had was caused by the video line when used on your TV. I'd be careful before declaring it the absolute that you are. I don't think we've had a rash of XRGB2+ users complaining about this problem before, and it goes without saying that your TV is quite a bit different from the animal that the XRGB2+ was originally made to sync up with. It is the nature of this stuff that you're going to find some finicky equipment that doesn't play well with others from time to time, I've not had your problem with my XRGB2+ though, and that the dither remains jailbars seems to point to something that your TV is doing that the upscan does not expect. Don't you think Lawrence himself would have noticed something like that years ago?

In the interest of science what TV is it that you are using?

[acem77]

chill?i was not heated just stating the facts for my problem and what solved it.
i have tried two pc monitors they both displayed the same artifacts until i remove the composite garbo..
my main tv is a 56" dlp samsung hl-p5674w

[Vertigo]

Your main TV though probably also does some fancy picture processing crap which in my experience actually makes non-prog-scan pictures look like shit at a price which makes you feel like shit. It's for this reason that I'm sticking to my Panasonic CRT until flats and plasmas actually give out a decent picture at a price that isn't a kick in the bollocks.

[acem77]

i know i am part of a very small percent that has this many systems hooked up to a nice large tv with such clarity.
i am 101% happy with the picture i have now.
when it looks as sharp as an emulator running on my pc monitor i just know that is many steps closer to perfection.
yes it is blocky but that is the nature of the beast with legacy game systems.
if i really need to i can add scan lines, blur or shrink the picture or all of the above.
i dont like to add an artificial camouflage to cover up the pixels that are truly there.

[Paper]

Dude, chill out. You solved your problem, but did you use this with any other display? Including a PC monitor for that matter? All I am saying is that the problem you had was caused by the video line when used on your TV. I'd be careful before declaring it the absolute that you are. I don't think we've had a rash of XRGB2+ users complaining about this problem before, and it goes without saying that your TV is quite a bit different from the animal that the XRGB2+ was originally made to sync up with. It is the nature of this stuff that you're going to find some finicky equipment that doesn't play well with others from time to time, I've not had your problem with my XRGB2+ though, and that the dither remains jailbars seems to point to something that your TV is doing that the upscan does not expect. Don't you think Lawrence himself would have noticed something like that years ago?

In the interest of science what TV is it that you are using?

He is absolutely right.

I now have some personal experience in this as I tried my Mega Drive RGB cable, which exhibits interference from a yet undetermined source, on multiple displays when looking for a TV set.

On a Samsung and a JVC the interference was excessive to a horrifying degree, whereas a Blaupunkt did not show it that much; and a Philips did not show any interference whatsoever.

Same cable and Mega Drive in every case.

[acem77]

He is absolutely right.

I now have some personal experience in this as I tried my Mega Drive RGB cable, which exhibits interference from a yet undetermined source, on multiple displays when looking for a TV set.

On a Samsung and a JVC the interference was excessive to a horrifying degree, whereas a Blaupunkt did not show it that much; and a Philips did not show any interference whatsoever.

Same cable and Mega Drive in every case.

not the case with the the artifacts i had. it showed up on every thing i tried and went away after i redid a few things.
cause and effect simple.

jailbars seems to point to something that your TV is doing

they have to do with the xrgb2 plus and nothing with the tv. it does the same thing on a vga monitor. its something to do with how the saturn goes in to its high rez mode and how the xrgb2 plus works.

in the end that has nothing to do with many squares crawling up the screen. as in the 1st pic...

that is the problem i had and solved.

why cant most of you be more like Lawrence

Wow, that made a hell of a difference. Nice work.

why do i have to battle my point when i did some thing that worked?
it worked for me and most likely will work for someone else.

[atom]

You guys are really overcomplicating things. He found the problem and fixed it. As a rule of thumb, if you dont need a line in your cable, dont use it. Always shield your cables.  

[Vertigo]

Always shield your cables.

Yeh, this bit to Paper.
I will have to re-do my Megadrive RGB cable at some point too coz the guy who did it made a real mess of the innards, used crap sellotape instead of shrink tubing and etc and had problems which were fixed by jiggling coz the right speaker wire was actually touching the green wire inside.

[Paper]

Vertigo:
Aye, rewiring is my first priority.

acem77:
I think this is merely a misunderstanding related to difference in mother-tongue.
Let me explain what my post means.

It is an illustration and confirmation of Endymion's post. A post which was completely factual and accurate, but a post which was dimissed out of hand for no reason whatsoever. This needed to be recified.

I have never touched a Saturn, nor do I even know what a XRGB2 looks like. I am not qualified to express any comment whatsoever on your problem.

I do not see why you think you need to "battle". This thread seems to be completely civil as all other threads on this forum and is full of worthy and sincere advise.

[Vertigo]

I find it somewhat humerous that we're arguing about clarity of expression in a thread about RGB.
We're all happy modding friends here.
Except Lawrence. He's a miserable git

[fragment]

could you clarify want you meant by the following:

i have seen these artifacts in the snes cable before i change the original scart cables wire on the snes side.
they had the (pin 9)composite video as the sync . i switched it to just the (pin 3)composite sync.
now the picture is perfect.

I have a SNES S-video cable and it looks terrible (blocky).


Erik