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Scanlines on vector games?
protokatie:
--- Quote from: RandyT on October 05, 2008, 12:00:43 pm ---
--- Quote from: Ummon on October 03, 2008, 07:53:42 pm ---Yes, as I've been finding out in particular with the new AAE emulator. So, particularly as I've not seen the answer anywhere: WHY is a vector display so bright?? (Gimme as technical as you like.)
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Vector displays are bright because the duty cycle for the beam drawing the graphics can be much higher than with a raster monitor. The vector monitor literally draws the individual objects on the face of the CRT, so depending on how many objects there are, the amount of "on" time to "off" time can be greater than with a raster monitor. Of course, this also tends to make the objects "shimmer" because the brightness is always changing and more on-screen objects means more flicker. The phosphor on a vector CRT also tends to be of longer persistence (at least with the mono screens).
I tend to believe that a raster monitor with a very high refresh rate, and the output cranked, could actually approach the brightness of a true color vector monitor. The mono ones will always be nearly impossible to duplicate. They don't have shadow masks in them.
RandyT
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I prefer to call this the "oscilloscope" effect. Since an oscilloscope is essentially a vector monitor with long lasting phosphores... erm I mean, just like a vector monitor (Except with different control circuits to move the beam).
Your explanation is more in depth tho.
Matthew Fisher:
--- Quote from: RandyT on October 05, 2008, 12:00:43 pm ---
--- Quote from: Ummon on October 03, 2008, 07:53:42 pm ---Yes, as I've been finding out in particular with the new AAE emulator. So, particularly as I've not seen the answer anywhere: WHY is a vector display so bright?? (Gimme as technical as you like.)
--- End quote ---
Vector displays are bright because the duty cycle for the beam drawing the graphics can be much higher than with a raster monitor. The vector monitor literally draws the individual objects on the face of the CRT, so depending on how many objects there are, the amount of "on" time to "off" time can be greater than with a raster monitor. Of course, this also tends to make the objects "shimmer" because the brightness is always changing and more on-screen objects means more flicker. The phosphor on a vector CRT also tends to be of longer persistence (at least with the mono screens).
I tend to believe that a raster monitor with a very high refresh rate, and the output cranked, could actually approach the brightness of a true color vector monitor. The mono ones will always be nearly impossible to duplicate. They don't have shadow masks in them.
RandyT
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I hadn't thought about the duty cycle issue before, and that is undoubtedly a very large part of the equation, but I would like to add one more observation. The brightness of the "vectors" on the raster monitor wouldn't be the big problem, in my view, it would be the contrast. To me, much of the visual appeal of the vector monitor comes from the difference between the laser-like vectors and the blackness of the background. And it is truly black, as no electron is hitting those phosphors. In a raster, all of them are getting hit with every refresh, even if they are supposed to be black. I would be surprised if you could ever get a raster bright enough while still maintaining anything close to true black in the background. Just my two cents...
RandyT:
--- Quote from: Matthew Fisher on October 06, 2008, 10:13:52 am ---I hadn't thought about the duty cycle issue before, and that is undoubtedly a very large part of the equation, but I would like to add one more observation. The brightness of the "vectors" on the raster monitor wouldn't be the big problem, in my view, it would be the contrast. To me, much of the visual appeal of the vector monitor comes from the difference between the laser-like vectors and the blackness of the background. And it is truly black, as no electron is hitting those phosphors. In a raster, all of them are getting hit with every refresh, even if they are supposed to be black. I would be surprised if you could ever get a raster bright enough while still maintaining anything close to true black in the background. Just my two cents...
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While I fully agree with you regarding the contrast being another difference, I don't necessarily believe that high contrast and high brightness need to be mutually exclusive on a raster screen. And IIRC, some of those old color vector monitors used a gray phosphor, which meant a tinted window or exterior light control was a real necessity to give you that dark screen.
But considering where we are in the current state of technology, a raster CRT discussion is kind of moot anyway. High resolution LCD panels (for now) are going to be the thing that gets the closest for a couple of reasons. The first is that the LCD pixel just turns on and stays on until told to turn off. This is, in essence, a 100% duty cycle. Second, contrast ratios and brightness can be, and usually are, very high on LCD screens. While the blacks aren't as intense on an LCD, the brightness and contrast levels open up the possibilities of using optical filters, like tinted glass / plexi, to tweak the output in order to get those dark blacks, as well as very acceptable brightness. As the black level specifications get better, either through technology advancements in LCDs or totally new technologies, I think we'll see displays that, with the proper software to simulate the phosphor trails and flicker, can approach or even surpass what the color vector monitors can deliver.
RandyT
Ummon:
--- Quote from: Matthew Fisher on October 06, 2008, 10:13:52 am --- As the black level specifications get better, either through technology advancements in LCDs or totally new technologies, I think we'll see displays that, with the proper software to simulate the phosphor trails and flicker, can approach or even surpass what the color vector monitors can deliver.
RandyT
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I suspect so, too. Same for native-like display on raster games, 15khz glow and all. However, until then, it's a matter of how determined one is.