How crappy of a TV do you need for composite video artifacts?

[Dogway]

Just read this line here, and thought it could be related to the rainbowing of the BW areas.

It is important to note that while the NES only generates eight (8) samples of NTSC signal per pixel, the wavelength for chroma is 12 samples long. This means that the colors of adjacent pixels get mandatorily mixed up to some degree. For the same reason, narrow black&white details can be interpreted as colors.

By the way, just a little bit lower they justify the use of the “FCC-sanctioned YIQ-to-RGB conversion matrix”

@Nesguy Found this on comb filters, no formulas but good explanations, in case you haven’t read it already.

[Jamirus]

Related, found this 2 page RGB-Composite comparison about the output of various consoles interesting - check out the Neo Geo at the bottom - composite looks terrible! Not entirely surprising because of the arcade origins, but there’s no S-Video on the homesystem either.

https://www.chrismcovell.com/gotRGB/rgb_compare.html

[Jamirus]

I got a new CRT - a 14" inch one which was supposed to be barely used. Compared to my old 20 inch one it looks a good deal sharper, and portability and rotation is a big plus. Testing the inputs, I got back to the Wii to check the composite. I was astonished again how good it looks , but this prompted me to think if I could maybe degrade the signal to make it closer to original systems without using any emulator filters. I had an unused DVD-Recorder around, so I plugged the Wii into the CAM AV input there and used the Recorder’s own composite output to plug into the TV. That made the picture significantly worse, way more blurrier. There still not much going on in terms of dot crawl or other things you’d associate with old composite outputs, but might be an interesting thing to try if you only have the modern stuff around.

I took some photos, but currently I also have to experiment with some camera apps on a custom rom’ed phone, still they might give a hunch of how it looks. First pic is always Wii directly connected, second via recorder.

[Nesguy]

Nice photos!

What’s the model number? I wonder what kind of comb filter it has.

[alexb3d]

“Curiously” youtube showed me this video after reading this post, it’s interesting.

Dithering on the Sega Genesis with Composite Video

[Jamirus]

This is an AEG CTV 4800 VT. Likely some cheap thing made at the end of the CRT lifecycle. But as I wrote, the selling point here was that the tube hasn’t seen much action. I was originally talking to someone for possibly getting a nice blue Orion, but that model was considerably older, and the guy couldn’t tell me if the SCART input accepted RGB, so that was a no-go. I’ll probably get another 14 inch one for aesthetics and comparison, and maybe a larger Trinitron if I find one in the 16"-19" range.

[DariusG]

That composite is only useful on some 8bit like Atari 2600 and Zx spectrum to hide the jaggies. Everything else looks way better on RGB. I have a Wii and a PC to Trinitron and I can tell you that for sure.

Some Megadrive games too with heavy dithering. Sometimes though I enable an ntsc shader on that systems to filter the image a bit to look authentic on CRT.

[Nesguy]

A lot of SNES games relied on composite video tricks as well. Basically anything from the composite video era should use composite video because the graphics were likely designed with that output in mind.

I use GDV and use a custom NTSC mode to minimize undesirable artifacts while still blending stuff that should be blended.

[Jamirus]

Took some photos recently for social media, might be interesting for some here as well: Wii composite can be very sharp. Still, notable difference with RGB. Third pic is with Blargg’s composite filter activated.

Now, I did get another, older CRT from around 1995, and the composite is notably worse (more color bleeding etc.), but it’s not entirely clear to me to what extent this is due to it’s condition, when I received it, the composite looked so bad I thought it was unusable. After some adjustments I managed to make it look ok, at least for my purposes - it’s an analog chassis (useless service mode), probably won’t mess around too much with the pots, at least for the near future.

[hunterk]

Indeed, the comb filters used to re-separate the individual luma and chroma from the composite signal got significantly better (and the best of them got significantly cheaper, making them available in more models) toward the end of the CRT era.

[Syh]

Lovely shots, what TV is it?

Nintendo makes solid AF cables as well which helps. (Cable quality matters, my wallet cries because of it

You can get component cables for your Wii and your wallet can cry too )

[DariusG]

Amiga with composite looks very sharp on early 2000’s Trinitron, of course still not as good as RGB. Still it blends dithering to a new color but nowhere near the blurriness of filters like blargg etc. It’s much more clear and almost no artifacts.

[Cyber]

@DariusG

Still it blends dithering to a new color but nowhere near the blurriness of filters like blargg etc. It’s much more clear and almost no artifacts.

I wholeheartedly agree.

To me most filters that behave like this including GTU Default Settings simulate a composite VHS Tape output signal and not necessarily a good composite signal coming from an NES, SNES or TurboDuo.

[Syh]

Honestly I feel like alot of people associate “shitty composite signals” with VHS/VCRs, unintentionally mind you. (I’m meaning alot of people went composite out of the console, into the VCR and out to the tv either with rf or composite; either way not good, you’re degrading the signal and filtering it additionally by running it through a VCR)

Tldr; People mistakenly think composite is worse than it is because of running it through a VCR causing extra filtering and signal degradation. Also shitty cables = equal noisy, unclear picture.

[Jamirus]

It’s the same as a couple of posts back (AEG VT 4800, 14-15" size, I haven’t measured it yet). I.e. this is something you would maybe pick up for a low price in a retail store (like Walmart maybe? don’t know about the US). From what I read, it is better to get something that’s essentially “fresh” rather than a CRT from a top-brand that was used thousands of hours. Budget CRT TVs are also supposed to have a potentially more “natural look”, because manufacturers started to shove more and more image processing into their products.

I do have in fact component cables (3rd party, no way I’m going to pay the ridicoulous prices for Nintendo stuff). They’re just pretty useless for CRT TV use in Europe. I got them for 480p LCD use. Funnily enough, 480p was screwed up by Nintendo as well, there was a bug discovered that degraded image quality only fixed via homebrew a few years ago.

[Syh]

Hopefully at the end of the month I’ll be able to test both my CRTs via all three of their inputs with my Mister, just waiting on a different video PCB for it and a component cable.

Should be able to test composite, S-Video, and component. (Just hope my composite/S-Video cable isn’t garbage ; bought a retrobit Saturn cable)

[theflyingape]

lol, “80s”? Most of us were still using the living room TV console from the 70s, because it was the only television in the house. That said, my first one was a cheap RCA 10" B&W “sportable” coupled with a VIC-20 in 1982 – but because it was B&W, it was very crisp.

But when I moved the VIC onto the (big) Zenith color TV, the “chroma noise”(?) it made on the display & speakers meant a LOT of manual adjustment to color / contrast / luma which “muddied” the picture some but was much more tolerable to watch & listen.

I remember there was a huge shortage / backorder of home computer monitors in 1983-1984 with price gouging, and I didn’t get my first one until 1985. But composite video from any set in the 80s were solid given VHS tapes & Camcorders were all the craze. It was the original RF modulator connected to the antenna for a UHF channel (pre-cable 70s TVs) made for the early 8-bit machines that these crappy video artifacts are emulating. The simple CRT Pi effect is enough and making it fit in a retro bezel is more important (to me):

[Jamirus]

Had an USB grabber around that I used for some VHS conversions, that gave me idea to try to grab Wii and PS2 emulation composite via that and then also see how output would end up on my 95er (Blaupunkt) TV set. Lots of issues popping up though.

Wii composite: Couldn’t get colour for the 60hz mode from the grabber (doesn’t seem to like PAL60 which the Wii outputs instead of NTSC). So I had to stick to 50hz for these.

TV

PS2 composite: None of the recent Retroarch builds with 240p support worked for me. So I had to switch to an FCEU derivate without palette support. Unlike the Wii, PAL-consoles output NTSC in 60Hz mode. But the TV can’t handle NTSC

Anyway, changing standards for the grabber works, NTSC:

PAL:

Looks like the emulator wrongly scales to 256 lines in the vertical direction instead of keeping it at 240 so you have additional scaling artifacts instead of composite ones

From TV:

There’s also a half decent C64 emulator in the form of a Vice Port, but it doesn’t change aspect ratio in NTSC mode. So it’s really worth it only for PAL anyway imho.

Grabs:

TV:

Differences aren’t earth shattering, PS composite looks a notch worse than Wii, I think it’s a bit more obvious on my other TVs. The 95er set isn’t that much worse as I initially thought, it’s good deal blurrier, sometimes more dot crawl, e.g. appearing in Wii menus that my other sets don’t have like that.

[DariusG]

Yeah that’s not blur actually but it’s like 10-20% opacity of the original raw image moving here and there like convergence or something. The Amiga can do pretty sharp composite too, blending dithering but still sharp.

[Nesguy]

The CRT shots look sharper than the raw captures, which leads me to believe that it’s something to do with how the CRT works that makes NTSC output on a CRT look sharper compared to any of the shaders I’ve seen.

Alas, here’s GDV at horizontal sharpness 15.00 and subtractive sharpness 1.50, NTSC blend mode = 2.

It seems like the CRT is still sharper, or am I crazy?

(also, my god that red )