60fps video Showing Composite vs S-video vs RGB

[Fusion916]

I'm in the process of making a SCART/RGB switch with multiple simultaneous outputs, gave me the opportunity to capture the differences between composite, s-video, and RGB right next to each other (selecting between each with a sony PVM). Decided to make a quick vid and post it to show the dramatic difference.



Here is the video

https://www.youtube.com/watch?v=-4CnjzQ3GiQ

I haven't looked at s-video in quite awhile but it's amazing the difference between Composite and S-video. I don't remember the difference being that dramatic

Composite looks completely unplayable

[Dochartaigh]

What S-Video cable are you using (I've had bad luck with non-thickly shielded ones)? Since S-Video and RGBs share the same luminance? signal? (which also gives what we would call the same sharpness?), the only difference between those signals should be color then, correct?...but is it my imagination or do the scanlines get thicker on RGB? Possibly even a sharper image on RGB which I thought all the pros say shouldn't happen (I'm assuming the video sequence goes Composite > S-Video > RGBs?).

[Xer Xian]

Actually, RGB doesn't have a dedicated luma signal. S-video shares the same luma signal with composite, the difference is it just travel on a separate channel and is not meshed together with the chroma portion.

While an S-video signal can probably never be 100% as good as RGB, I never find myself longing for moar quality whenever I hook up a console to my TM-H150CG through (official) S-video cables. Here's a LttP shot on a 1CHIP SNES through S-video:



Colors are a bit muted but it's due to the camera. They are probably still 5% off with respect to RGB, but honestly, for 15kHz-only sources I wouldn't mind sticking S-video at all (but this is on my setup - who knows, other monitors may behave worse with it).

[Dochartaigh]

Actually, RGB doesn't have a dedicated luma signal. S-video shares the same luma signal with composite, the difference is it just travel on a separate channel and is not meshed together with the chroma portion.

That's what I get for quoting another member of the forum! (even wrote it down in my notes!). I thought the "Y" (Luma) in S-Video carries the luminance and sync? So a RGBs cable, using Sync on Luma, would be how I described it then? (a la PS1/PS2 - maybe others but those are the only Sync on Luma onces I know off the top of my head).

So on regular RGBs, which uses composite sync, where is the luminance signal carried? (couldn't find that on the Wiki and a few other pages I read).

While an S-video signal can probably never be 100% as good as RGB, I never find myself longing for moar quality whenever I hook up a console to my TM-H150CG through (official) S-video cables. Here's a LttP shot on a 1CHIP SNES through S-video:

Lol, that's the same monitor (and it's bigger brother the 750 TVL S-Video only TM-H1700G) that changed my mind about S-Video as well. KILLS my 600 TVL Sony's over RGB...

[Ryoandr]

RGBs doesn't exist (I think ?). Putting the s in lower case means it's embedded in the previous signal letter ; capital S means it travels on it's own cable, either pure or embedded in another signal.
The most common signals are
RGBS (with sync being alone or carried with composite or luma)
RGsB aka sync on green, the PS2 does this when forcing 480p
RGBHV, typical PC VGA signal.

As for s-video / composite luma signal, it's theoricaly the same, except on composite it has to be low filtered because of the 3.57/4.43 mhz colorburst. With s-video luma has no filter and chroma is carried for the entire length of the scanline (the colorburst is still here, that's why you can do a crude composite adapter with a cap on the chroma line).

And yeah, JVC monitors do wonders in S-video.

[FinalBaton]

I can't see your pic when I click on it, Xer Xian : (

[Harrumph]

So on regular RGBs, which uses composite sync, where is the luminance signal carried? (couldn't find that on the Wiki and a few other pages I read).

You're mixing up two different things. RGB does not use luminance because brightness is determined by the sum of the three colours. Like with sync on composite video, when using sync on luma for RGB, only the sync is utilized and the other information is ignored

[Xer Xian]

@Dochartaigh:
RGB just doesn't need luma - this excerpt from Wikipedia sums it up well:

zero intensity for each primary gives black while full intensity gives white. [...] When the intensities for all the components are the same, the result is a shade of gray, darker or lighter depending on the intensity. When the intensities are different, the result is a colorized hue, more or less saturated depending on the difference of the strongest and weakest of the intensities of the primary colors employed.

To my understanding, splitting the information into luma and chroma was a trick devised to 1) retain compatibility of color TV broadcast with monochrome sets (along with some other gimmick that escapes me) and 2) allow to reduce the signal bandwidth by subsampling the chroma portion (ie not full 4:4:4 but 4:2:2 or 4:2:0). Mind you, that's cursory knowledge - you would be better off reading actual books (linky) rather than me or another random forum member.


@FinalBaton
Maybe here it's better? -> https://ibb.co/fArQWG
Here's an older one - DDP on the same monitor, still S-video: https://postimg.org/image/8vr6gd28f/

[Xer Xian]

you would be better off reading actual books (linky) rather than me or another random forum member.

Quoting myself because after re-reading I realized that this bit might come off as condescending to Dochartaigh or others - I had no intention. There are lots of very knowledgeable people around here, and reading posts is a great way to learn stuff. In some cases though (like when there are reference textbooks available on the matter), skipping to the direct source is a better and quicker way to find answers. Peace to all

[Dochartaigh]

you would be better off reading actual books (linky) rather than me or another random forum member.

Quoting myself because after re-reading I realized that this bit might come off as condescending to Dochartaigh or others - I had no intention. There are lots of very knowledgeable people around here, and reading posts is a great way to learn stuff. In some cases though (like when there are reference textbooks available on the matter), skipping to the direct source is a better and quicker way to find answers. Peace to all

You didn't in the least. I find people around here to be pretty darn friendly. But I'm still not going to read an 800 page book... lol

[tjstogy]

Fusion have you sent one of these to Voultar for testing yet? Or retrorgb have you?

[Fusion916]

Fusion have you sent one of these to Voultar for testing yet? Or retrorgb have you?

Are you talking about the board(s) in the OP? If so no, it’s still under development. Will probably be available soon though.

[tjstogy]

The scart to component converter?

Fusion have you sent one of these to Voultar for testing yet? Or retrorgb have you?

Are you talking about the board(s) in the OP? If so no, it’s still under development. Will probably be available soon though.

[Fusion916]

The scart to component converter?

Fusion have you sent one of these to Voultar for testing yet? Or retrorgb have you?

Are you talking about the board(s) in the OP? If so no, it’s still under development. Will probably be available soon though.

Retrorgb has reviewed it on one of his videos. Don't remember which sorry.

[tjstogy]

The last thing he said about your converter was:

EDIT: Through further testing, it seems there are some scenarios where there are color issues. I'll keep testing.

[Fusion916]

The last thing he said about your converter was:

EDIT: Through further testing, it seems there are some scenarios where there are color issues. I'll keep testing.

Where was this? I have not had any reports of color issues from anyone who have purchased the converter (over 100 people). I'm willing to bet side by side (same monitor) the colors look nearly identical (RGB vs Component).

[tjstogy]

viewtopic.php?f=6&t=58955&start=60

Also-- Guspaz pointed out features your converter is lacking:

What IC is the Shinybow using, I wonder, that it works with both sync-on-green and composite video sync and csync? Could this IC be used in homebrew products?

I'm trying to uphold some accountability.... Just because a forum member here manufacturers something, doesn't inherently make it a good product. As was suggested in the other thread by Voultar, you should send him one of your converters to see if the thing is actually any good. To someone who doesn't know any better, even the CSY clone is fantastic. You've stated in the other thread that you would send it for free to someone just as long as they have a good youtube following and can post a (good) review. (In this case, maybe Adam Koralik can help..... )

Again, maybe your product rocks, but maybe it sucks.... so dancing around people's critiques and offers to test your products unless it's for free promotion.... not kosher, IMO.

The last thing he said about your converter was:

EDIT: Through further testing, it seems there are some scenarios where there are color issues. I'll keep testing.

Where was this? I have not had any reports of color issues from anyone who have purchased the converter (over 100 people). I'm willing to bet side by side (same monitor) the colors look nearly identical (RGB vs Component).

[Fusion916]

Accountability? I'm completely transparent with my products. I've always stated it doesn't support sync on green and don't plan on making any modifications. Only composite video and composite sync.

I've already sent one to Rob and hes reviewed it. I'm confident in the product and had zero complaints on color or any other incompatibilities so I'm fine not sending out anymore free products to people for reviews. Again, I've sold over 100 of them, many people buy multiplies (repeat customers), so everything is good for me as is.

[BONKERS]

You are welcome to buy one and test it yourself if you really have such doubt. (Or the other person)

Take one for the team.
Or you know, you could sift through RetroRGB's videos to find the one that satisfies your curiosity.

[Fusion916]

You are welcome to buy one and test it yourself if you really have such doubt. (Or the other person)

Take one for the team.
Or you know, you could sift through RetroRGB's videos to find the one that satisfies your curiosity.

In addition to this I offer full return policy in the ebay auction (or if you buy them from me on here).