Why do some prefer consumer CRTs over PVM|BVM?

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Guspaz
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Re: Why do some prefer consumer CRTs over PVM|BVM?

Post by Guspaz »

Einzelherz wrote:Maybe it's a dumb question but why couldn't you install a similar board between the YUV plugs on a modern CRT and feed the set RGB?
That board is converting from RGB to YPbPr, not the other way around. Although IIRC, Tim's board doesn't output the Y, since the NESRGB already does?
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Einzelherz
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Re: Why do some prefer consumer CRTs over PVM|BVM?

Post by Einzelherz »

Guspaz wrote:
Einzelherz wrote:Maybe it's a dumb question but why couldn't you install a similar board between the YUV plugs on a modern CRT and feed the set RGB?
That board is converting from RGB to YPbPr, not the other way around. Although IIRC, Tim's board doesn't output the Y, since the NESRGB already does?
And most consumer sets in the USA accept YPbPr hence using that conversion.
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Guspaz
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Re: Why do some prefer consumer CRTs over PVM|BVM?

Post by Guspaz »

Oh, well, in that case you're missing the luma. What I'd really like is a SCART or BNC input adapter for the HDR Genesis cable... so that you could use it as a generic final step in the display chain between your otherwise fully RGB setup, and your component-only display. For example, all your RGB consoles go through all your gear and probably end up in a PVM, well, you could run the RGB outputs of the PVM into your HDTV or projector directly using the HDR cable.

There are lots of other RGB-to-component solutions out there, but they seem to either be OK-quality CSY-2100 clones, or rather pricey.
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Re: Why do some prefer consumer CRTs over PVM|BVM?

Post by bobrocks95 »

Guspaz wrote:Oh, well, in that case you're missing the luma. What I'd really like is a SCART or BNC input adapter for the HDR Genesis cable... so that you could use it as a generic final step in the display chain between your otherwise fully RGB setup, and your component-only display. For example, all your RGB consoles go through all your gear and probably end up in a PVM, well, you could run the RGB outputs of the PVM into your HDTV or projector directly using the HDR cable.

There are lots of other RGB-to-component solutions out there, but they seem to either be OK-quality CSY-2100 clones, or rather pricey.
Still baffled there's no big hobbyist converter project out there for it. The Garo goes the wrong way!
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Guspaz
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Re: Why do some prefer consumer CRTs over PVM|BVM?

Post by Guspaz »

Well, I'm also considering the Garo to simplify the input side of my setup. I'll run all my component consoles into a component switch, run the output of the component switch into the Garo to get to RGB, run the output from the Garo into my SCART switch (which still has one input free), run the output of the SCART switch into my PVM, and then run the output of my PVM into an RGB-to-component converter and feed that into my projector. I've already validated that the projector (which is my main TV) detects 240p component as progressive, and skips deinterlacing, with only 33ms of latency.

That would mean component consoles would be converted to RGB and then back to component again, but it would save having to go into the PVM's menus to switch the signal type each time, allowing everything to be automatic (both the component and scart switches are automatics).

I've got a BNC to VGA adapter on order, just to see if the projector will accept a 15khz signal over VGA. That would save me having to do the final conversion to component.
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Re: Why do some prefer consumer CRTs over PVM|BVM?

Post by mvsfan »

Its not missing the Luma. I got it from the S-video pin on the multi-out. Works great.
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Re: Why do some prefer consumer CRTs over PVM|BVM?

Post by Guspaz »

mvsfan wrote:Its not missing the Luma. I got it from the S-video pin on the multi-out. Works great.
Not for your SNES install, he wanted it as a generic solution. The board doesn't output luma/sync, so it can't be used for arbitrary devices. Or rather the closest you could come would be to use it in a svid/rgb to component converter, and that might actually work in custom cables (so that you could get all the signals you need) for a variety of consoles, like the PS1.

In the end, though, the HDR cables with adapters would do that, and they work without the need for luma or csync.
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Re: Why do some prefer consumer CRTs over PVM|BVM?

Post by FinalBaton »

bobrocks95 wrote: Still baffled there's no big hobbyist converter project out there for it. The Garo goes the wrong way!
I can't wait for beharbros to make an RGB to component transcoder :)
the Kramer units are hard to find and quite expensive
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bobrocks95
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Re: Why do some prefer consumer CRTs over PVM|BVM?

Post by bobrocks95 »

Guspaz wrote:Well, I'm also considering the Garo to simplify the input side of my setup. I'll run all my component consoles into a component switch, run the output of the component switch into the Garo to get to RGB, run the output from the Garo into my SCART switch (which still has one input free), run the output of the SCART switch into my PVM, and then run the output of my PVM into an RGB-to-component converter and feed that into my projector. I've already validated that the projector (which is my main TV) detects 240p component as progressive, and skips deinterlacing, with only 33ms of latency.

That would mean component consoles would be converted to RGB and then back to component again, but it would save having to go into the PVM's menus to switch the signal type each time, allowing everything to be automatic (both the component and scart switches are automatics).

I've got a BNC to VGA adapter on order, just to see if the projector will accept a 15khz signal over VGA. That would save me having to do the final conversion to component.
Are you sure that's a simplification? Haha.

I can understand the appeal of making everything automatic though. Good luck figuring out what's wrong in the chain if something looks weird though...
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Einzelherz
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Re: Why do some prefer consumer CRTs over PVM|BVM?

Post by Einzelherz »

Guspaz wrote:
mvsfan wrote:Its not missing the Luma. I got it from the S-video pin on the multi-out. Works great.
Not for your SNES install, he wanted it as a generic solution. The board doesn't output luma/sync, so it can't be used for arbitrary devices. Or rather the closest you could come would be to use it in a svid/rgb to component converter, and that might actually work in custom cables (so that you could get all the signals you need) for a variety of consoles, like the PS1.

In the end, though, the HDR cables with adapters would do that, and they work without the need for luma or csync.
Why would I want to output luma or sync?

What I'm suggesting is that you install Tim's RGB->YUV converter into a TV as a simpler solution to converting the TV to RGB.
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Re: Why do some prefer consumer CRTs over PVM|BVM?

Post by Guspaz »

Einzelherz wrote:Why would I want to output luma or sync?
Because luma+sync are one of the three signals for component video, and Tim's board doesn't output it. RGB in, PbPr out. Without it, you will only have what his board outputs: PbPr, which is useless by itself.
Einzelherz wrote:What I'm suggesting is that you install Tim's RGB->YUV converter into a TV as a simpler solution to converting the TV to RGB.
This is not possible because you are missing the Y signal (luma) and the sync signal.

Tim's board was designed to be installed on his RGB boards where luma/sync was already available for s-video. The luma signal of s-video and component (the Y in YPbPr) is identical. Even those who are putting this board in the SNES are getting the luma from the SNES s-video out, and if you're installing this thing in a TV and expect to feed it RGBS and have it internally convert to YPbPr (component video), it can't do that.
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Re: Why do some prefer consumer CRTs over PVM|BVM?

Post by Einzelherz »

Why wouldn't the luma/sync pass through just like it does inside a console?
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Guspaz
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Re: Why do some prefer consumer CRTs over PVM|BVM?

Post by Guspaz »

Because not every console outputs s-video, and even those that do don't always have it on the same plug as RGB (like the NESRGB mini-din). SCART has no dedicated luma pin, so your proposed setup would only work with sync-on-Luma cables and nothing else.
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Re: Why do some prefer consumer CRTs over PVM|BVM?

Post by Einzelherz »

Does the Y channel have to be luma? Would a c-sync or composite signal not work? I could swear I've sent composite to the G plug on my TVs and I get a clean black and white luma-only image.
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Re: Why do some prefer consumer CRTs over PVM|BVM?

Post by Guspaz »

You'll see a black and white image with interference, because what you've got there is composite video without the colour signal being read. It'll technically work, but at that point why even bother if you're basing everything on the composite video signal?
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Re: Why do some prefer consumer CRTs over PVM|BVM?

Post by Einzelherz »

My point being you would still use the best sync signal any system would put out, you know, just like we do everyday with RGB. I.e. sync pass through + RGB - > PbPr conversion.
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Re: Why do some prefer consumer CRTs over PVM|BVM?

Post by Guspaz »

Uh, you'd be using composite video sync, the worst possible source for sync, and you'd be using a messed up video source for luma, with lots of interference. That will most likely look worse than s-video.
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Re: Why do some prefer consumer CRTs over PVM|BVM?

Post by Einzelherz »

Are you being intentionally obtuse now?
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Re: Why do some prefer consumer CRTs over PVM|BVM?

Post by BazookaBen »

No, Guspaz is telling you that you can't get a pure luma (Y) signal from composite video. Pure being the key word, there will be artifacts from the encoded color signal. Or at least that's how I understand it would work.
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Re: Why do some prefer consumer CRTs over PVM|BVM?

Post by Einzelherz »

BazookaBen wrote:No, Guspaz is telling you that you can't get a pure luma (Y) signal from composite video. Pure being the key word, there will be artifacts from the encoded color signal. Or at least that's how I understand it would work.
Yet most of us use a luma or c-sync signal already with our RGB setups. Why can't that just pass through into the Y channel?

And in my own experiments composite video into a green component socket receiving component looks clean since it ignores all of the chroma data (I think).
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Re: Why do some prefer consumer CRTs over PVM|BVM?

Post by bobrocks95 »

You can't just ignore chroma data, it's mixed into the signal. That's what comb filters are for, and the two channels can't be perfectly separated.
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Re: Why do some prefer consumer CRTs over PVM|BVM?

Post by Unseen »

Einzelherz wrote:Yet most of us use a luma or c-sync signal already with our RGB setups. Why can't that just pass through into the Y channel?
Luma is no problem, it is exactly what Tim's board was designed to take advantage of. Using C-Sync as the Y channel would give you a black picture because the signal does not carry any picture information at all, just sync.
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Re: Why do some prefer consumer CRTs over PVM|BVM?

Post by Ikaruga11 »

Unseen wrote:
Einzelherz wrote:Yet most of us use a luma or c-sync signal already with our RGB setups. Why can't that just pass through into the Y channel?
Luma is no problem, it is exactly what Tim's board was designed to take advantage of. Using C-Sync as the Y channel would give you a black picture because the signal does not carry any picture information at all, just sync.
Does Tim's N64 board output CSync?
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Re: Why do some prefer consumer CRTs over PVM|BVM?

Post by Einzelherz »

Unseen wrote:
Einzelherz wrote:Yet most of us use a luma or c-sync signal already with our RGB setups. Why can't that just pass through into the Y channel?
Luma is no problem, it is exactly what Tim's board was designed to take advantage of. Using C-Sync as the Y channel would give you a black picture because the signal does not carry any picture information at all, just sync.
Thank you, Unseen.
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