Not refering here to something like ancient consumer TVs pre slot mask or whatever, but the standard shadow mask you get with most PC and some pro monitors (Ikegami etc.). The lowest figure I’ve seen is 600 TVL. Do some of these displays get in a more typical TV range like 450?
It looks like the original dot mask patent belongs to Zenith, which they commercialized under the brand name Chromacolor and used in some consumer sets circa 1973.
These apparently had TVL ratings in the 400-ish range.
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This is pretty good info. I think the original Death To Pixels *.cgp preset by @Birm might have been based on something like this. It was and still is a beautiful preset.
400 TVL sounds a bit much for sets that could presumably not do RGB. Unless they calculated it differently. The NEC XM29 Plus manual for example states 500 for video (i.e. composite) and 600 for s-video. I forgot to mention that was thinking only about RGB (max) figures.
I’m having trouble finding any manuals or spec sheets from the era, but they need that much to be able to show an NTSC signal, right? For the XM29+, I think they’re just talking about the signal itself, since the max TVL should be a hardware limitation, right? And I know mine can show 1024x768, no problem.
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The XM29+ manual states that 1024x768 is the max. resolution with RGB yes. I was thinking that the kind of signal functions essentially as a cap, so in theory you could have larger jumps in resolution from one display to another when you use higher quality signals.
Yeah, that’s true. There’s also a physical limit. I’m not sure what all goes into it other than the horizontal sync rate, but the physical max TVL is apparently related to how sharp/defined the scanlines are and how big the gaps between them appear with low-res signals.
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