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Vector only MAME cabinet
RandyT:
Here's something that I have long suspected, but just now found verification of.
The following was taken from the Sci.Electronics Repair FAQ.
Chapter 2) How does a Vector monitor work?
Vector monitors, also referred to by Atari and others as "XY" (ick) or "Quadrascan" (double ick) monitors, are available in black and white or color. A black and white picture tube has one electron gun that lights just one type of phosphor (usually, but not always, white). Color tubes have 3 electron guns that, when the yoke and neck magnets are aligned properly, each hit their own phosphors only, either red, green, or blue (RGB). Something called a shadow mask is used so each gun hits only one set of phosphors. There is no inherent difference between the tubes used in vector monitors and the tubes used in raster monitors; only the control circuitry differs. That is not to say that you can use any tube in any monitor; there are several different neck pinouts that have been used for picture tubes so you have to find a tube with a matching pinout first. If you have a lot of screen burn, you can replace a color vector picture tube with any compatible "off-the-shelf" 100 degree in-line picture tube that is also used in raster-scan displays.
I always thought I could see a color mask on those color vector monitors.
So this means that while the scanning method is different on the color vector monitors, the actual picture produced by them will have a dot pattern based on the dot-pitch of the color masks.
In other words, aside from a couple of nuances like flickering and possibly intense brightness, there should be very little difference between the image on a color vector monitor and a hi-resolution (better than 1024x768) color PC monitor.
My calculations, based on a 19" monitor and .31 dot pitch (I doubt they were using .25 in those days), give me a horizontal resolution of about 1227 and a vertical of about 920. So in essence, a PC display of 1280x1024 on a .25 - .27 dot pitch display would actually have a higher resolution than a color vector display.
Now what would be interesting is if someone could find a hi-res mono-vga and see what one looks like with a B&W vector game. Anyone?
RandyT
Xiaou2:
I think thats the point. Its the intense brightness that is most important to making the vector monitors highly desireable to any who have seen them in action.
I hadnt seen one in a long time... but after seeing again, realized how cool the effect was - and would really like to have the same effect in my machine somehow.
Frostillicus:
Yes it is well known that vector tubes are the same as raster tubes, it's just the type of and number of guns that are different (apart from the control circuitry and signal type, obviously). A vector monitor will always look superior to raster due to the fundemental differences in producing the image: point-to-point vector vs raster horizontal scanning. I agree games look decent on hi-res vga monitor but they don't approach vector monitor quality, IMHO.
Tailgunner:
--- Quote from: Xiaou2 on February 15, 2004, 03:45:23 pm ---
Well... i myself have been thinking about this latly.
While its true... you can get ok results from a high res pc monitor... theres really a huge difference, mostly in brightness. If the pixils are small enough (like in asteroids bullets)... they glow so brite that its like looking at the sun!
There are a few ways to simulate this artistically... but still will probably come up short..
However... there is a fairly simular technology that could probably do the same effects the same or Better than a vector monitor:
LASERS! ^_^
There was a site about a project called Lasermame. Was a modified version of mame that only played vector games using a laser as a display device. It looked incredible.
The cost of lasers have really come down... and even the complex controllers too. Ive seen laser light show devices on ebay that are arround 100$ to 250$ that have a huge array of features.
If we could convince a company to make a laser projector for us mame peoplee... i think there would be a huge demand for them.
Imagine playing tron in your cab... then exiting... and starting up a game of tempest. The main monitor would go off... and the laser would pop the display right on top of the darkened monitor. (maybe mount the laser overhead and behind the players?)
whats great about the lasers.. is that you can project onto any surface... and scale it to almost any distance...
--- End quote ---
What I'd rather see would be someone building replacement vector arcade monitor chassis boards like the ones 8-Liners imports. Or better yet, a combination vector/raster monitor chassis, since there isn't any difference in the tubes. That way you could play both vector games and raster games on the same monitor, and still have both look correct.
RandyT:
--- Quote from: Frostillicus on February 15, 2004, 09:02:56 pm ---Yes it is well known that vector tubes are the same as raster tubes, it's just the type of and number of guns that are different (apart from the control circuitry and signal type, obviously). A vector monitor will always look superior to raster due to the fundemental differences in producing the image: point-to-point vector vs raster horizontal scanning. I agree games look decent on hi-res vga monitor but they don't approach vector monitor quality, IMHO.
--- End quote ---
The type and number of guns are identical. There is still a "grid" pattern on a color vector display due to the shadow mask. Only the circuitry that controls them differs in that instead of scanning left to right, top to bottom, it paints the image like a laser light show would. The flickering is due to slow refresh rate and the "trails" are due to the long persistance phosphor, which is used to help tone down the flickering.
Granted, the image on some color vector monitors may be brighter. I can't say for sure because aside from my trusty B&W Vectrex here, I haven't seen a true vector monitor in quite a while. But I honestly don't recall them being that much brighter. In fact, some of the machines were downright dim, but they could have been turned down or failing. One would think that the brightness would be decreased due to the slow refresh rate and flickering. Sure, you can crank them up, but they aren't very pretty that way (usually they start showing the connecting traces when you do that). They are also more prone to burn in because the electron beam doesn't paint the surface evenly. So there's another reason not to keep them cranked up super bright.
One thing that is markedly different is contrast. On a raster monitor, the eb gun is scanning the entire surface of the screen, even the "black" areas. This causes the phosphor in those areas to glow slightly (very dark gray). On a vector monitor, the phospor in the unused areas is, for the most part, dead. So there is a level of contrast that is virtually unachievable by any other display technology (other than lasers at midnight with no moon).
But I guess my point really was....if you use a grid that is 1280x1024 (PC resolution) and one that is 1227x920 (color vector resolution) and then draw a thin point to point line on each of them, you would likely find very little discernable difference in the sharpness of the image. Factor in less than perfect convergence and focus, and I'd expect it to be moreso.
Someone with a real Star Wars machine needs to do a "side-by-side" comparison. :)
RandyT