4 ms·

Can’t you still just use a real CRT? Or is it then just back to the latency question?

by mikepurvis 1y ago

treve 1y ago
For me they are weirdly hard to obtain. Don't show up in second hand shops. Ebay shipping is prohibitively expensive.
- reverius42 1y ago
  They are truly dying out. Wish I'd kept my color c64 monitor -- it would probably be worth a lot now (or at least would be awesome to use for retro purposes).
- mikepurvis 1y ago
  Interesting. I still have a bunch showing on my local Facebook Marketplace, but who knows what shape they’re in plus it probably varies a lot from city to city. I can well imagine that it’s gotten expensive finding a quality one (eg trinitron) of reasonable size.
- mark-r 1y ago
  They don't show up in second hand shops because their value is essentially negative. If it doesn't sell, you have to pay to dispose it.
Telaneo 1y ago
CRTs wear out with use, so they're only getting rarer by the day. The electronics can mostly be fixed, but the tubes can't. You can extent their lives a bit, but you're only delaying the inevitable. When it's gone (too low brightness, burn-in, bad focus), there's nothing that can be done about it to get it back to the way it was when it was new.
- actionfromafar 1y ago
  That's almost true, but just almost. Behold: https://colorvac.de/service/ https://colorvac.de/service/
- trollbridge 1y ago
  Every small city used to have a repair shop that could fix them.
  - bawolff 1y ago
    Were there really companies repairing the phospher wearing out? Repairing the tvs, sure, but i find it hard to believe there were repair shops for the issue parent was mentioning.
    - numpad0 1y ago
      No. Repairing phosphors require complete removal of phosphor layers and re-application using basic multi step deposition for RGB strips, on the inner surface of the tube. That's not a shop repair.
  - a96 1y ago
    Re-adjust, not fix.
- ssl-3 1y ago
  There was some repair available. At very least, the neck could be cut off, and the electron gun bits replaced with new. According to the Vintage Television Museum near Columbus, Ohio, the last company in the US to be able to do this closed in 2010, and the last one remaining in Europe closed in France in 2013. (I myself don't know if there are any in some other corner of the world.) The museum did succeed in getting a bunch of the repair equipment from the shop in France, and one person involved was even trained there, but it's been a very long process. Currently, the equipment seems to be in Maryland in the care of a person named Nick Williams. The last update I can find from him[2] is a few years old, and expressed concern about the war that had recently begun in Ukraine affecting the supply of electron guns. tl;dr, it may still be possible to repair some aspects of some CRTs, and doing so is apparently not a completely-lost art -- yet. [1] https://www.earlytelevision.org/crt_project.html https://www.earlytelevision.org/crt_project.html [2] https://www.earlytelevision.org/nick_report_5-1-2022.html https://www.earlytelevision.org/nick_report_5-1-2022.html
  - actionfromafar 1y ago
    Colorvac.de is in Germany
numpad0 1y ago
Who's spreading that CRT latency thing? Latencies for CRTs are in nanoseconds.
- mikepurvis 1y ago
  Right but you still have the latency of frame buffers inside the emulator, plus more again when that’s converted out to analog, especially if an HDMI connector is still in the mix— ideally you’d do this on original hardware or at least a PC with a graphics card that has native s-video or VGA outputs.
  - numpad0 1y ago
    You only need one pixel worth of RAM to display HDMI input into a CRT. You don't need to buffer the whole thing, at all. Especially if you were driving the tube with your own driving circuit.
    - mikepurvis 1y ago
      Most monitors and TVs do buffer at least a whole frame because of the processing, scaling, etc that they're doing: https://www.rtings.com/monitor/tests/inputs/input-lag https://www.rtings.com/monitor/tests/inputs/input-lag That said, yeah, in the special case of an HDMI-driven CRT that was specifically designed with ultra low latency in mind, you could buffer way less than a frame— though I imagine you'd probably want to buffer at least a line at a time just for sanity with the timing of driving the electron gun. And obviously this would depend on the HDMI picture resolution exactly matching that of the CRT.
      - numpad0 1y ago
        HDMI is RGB plus clock in 4 differential pairs. Fundamentally you just need 3 shift registers with reset tied to clock. Out comes the signal and you wire that to RGB electron guns through an E24 resistors assortment pack. LLMs probably don't know enough about them to be useful in this discussion. Classic Google Search would be better. Yours fixating on pixels shows that.

Can’t you still just use a real CRT? Or is it then just back to the latency question?

treve 1y ago

For me they are weirdly hard to obtain. Don't show up in second hand shops. Ebay shipping is prohibitively expensive.

reverius42 1y ago
They are truly dying out. Wish I'd kept my color c64 monitor -- it would probably be worth a lot now (or at least would be awesome to use for retro purposes).
mikepurvis 1y ago
Interesting. I still have a bunch showing on my local Facebook Marketplace, but who knows what shape they’re in plus it probably varies a lot from city to city. I can well imagine that it’s gotten expensive finding a quality one (eg trinitron) of reasonable size.
mark-r 1y ago
They don't show up in second hand shops because their value is essentially negative. If it doesn't sell, you have to pay to dispose it.

Telaneo 1y ago

CRTs wear out with use, so they're only getting rarer by the day. The electronics can mostly be fixed, but the tubes can't. You can extent their lives a bit, but you're only delaying the inevitable. When it's gone (too low brightness, burn-in, bad focus), there's nothing that can be done about it to get it back to the way it was when it was new.

actionfromafar 1y ago
That's almost true, but just almost. Behold: https://colorvac.de/service/ https://colorvac.de/service/
trollbridge 1y ago
Every small city used to have a repair shop that could fix them.
- bawolff 1y ago
  Were there really companies repairing the phospher wearing out? Repairing the tvs, sure, but i find it hard to believe there were repair shops for the issue parent was mentioning.
  - numpad0 1y ago
    No. Repairing phosphors require complete removal of phosphor layers and re-application using basic multi step deposition for RGB strips, on the inner surface of the tube. That's not a shop repair.
- a96 1y ago
  Re-adjust, not fix.
ssl-3 1y ago
There was some repair available. At very least, the neck could be cut off, and the electron gun bits replaced with new. According to the Vintage Television Museum near Columbus, Ohio, the last company in the US to be able to do this closed in 2010, and the last one remaining in Europe closed in France in 2013. (I myself don't know if there are any in some other corner of the world.) The museum did succeed in getting a bunch of the repair equipment from the shop in France, and one person involved was even trained there, but it's been a very long process. Currently, the equipment seems to be in Maryland in the care of a person named Nick Williams. The last update I can find from him[2] is a few years old, and expressed concern about the war that had recently begun in Ukraine affecting the supply of electron guns. tl;dr, it may still be possible to repair some aspects of some CRTs, and doing so is apparently not a completely-lost art -- yet. [1] https://www.earlytelevision.org/crt_project.html https://www.earlytelevision.org/crt_project.html [2] https://www.earlytelevision.org/nick_report_5-1-2022.html https://www.earlytelevision.org/nick_report_5-1-2022.html
- actionfromafar 1y ago
  Colorvac.de is in Germany

numpad0 1y ago

Who's spreading that CRT latency thing? Latencies for CRTs are in nanoseconds.

mikepurvis 1y ago
Right but you still have the latency of frame buffers inside the emulator, plus more again when that’s converted out to analog, especially if an HDMI connector is still in the mix— ideally you’d do this on original hardware or at least a PC with a graphics card that has native s-video or VGA outputs.
- numpad0 1y ago
  You only need one pixel worth of RAM to display HDMI input into a CRT. You don't need to buffer the whole thing, at all. Especially if you were driving the tube with your own driving circuit.
  - mikepurvis 1y ago
    Most monitors and TVs do buffer at least a whole frame because of the processing, scaling, etc that they're doing: https://www.rtings.com/monitor/tests/inputs/input-lag https://www.rtings.com/monitor/tests/inputs/input-lag That said, yeah, in the special case of an HDMI-driven CRT that was specifically designed with ultra low latency in mind, you could buffer way less than a frame— though I imagine you'd probably want to buffer at least a line at a time just for sanity with the timing of driving the electron gun. And obviously this would depend on the HDMI picture resolution exactly matching that of the CRT.
    - numpad0 1y ago
      HDMI is RGB plus clock in 4 differential pairs. Fundamentally you just need 3 shift registers with reset tied to clock. Out comes the signal and you wire that to RGB electron guns through an E24 resistors assortment pack. LLMs probably don't know enough about them to be useful in this discussion. Classic Google Search would be better. Yours fixating on pixels shows that.