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Trick with using PC CRT
Ginsu Victim:
--- Quote from: Ummon on July 15, 2008, 07:12:53 pm ---
--- Quote from: ahofle on July 11, 2008, 03:30:26 pm ---
--- Quote from: megaultrasuper on July 11, 2008, 12:55:28 pm ---One cool thing you can try with a pc crt is 31.5 khz modes. Several old CRT monitors can handle this.
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Isn't that what the OP is suggesting? (640x480 = 31khz)
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Yes, 640x480 is 31khz. Even at 800x600, these monitors will produce hardware scanlines. It's at 1024x768 and above that they don't. In any case, it literally takes seconds to try this out if you have a PC CRT hooked up to a computer with Mame32/UI: start it, select the appropriate properties in DK, and start the game. Exit, switch to vertical orientation, and start the game.
I don't know what resolution mega's running at. I'd like to see his rc file. Of course, these monitors will also go past 120hz, so there's that option, too. I don't prefer it because the blank lines are almost as thick as those drawn. It's a matter of dot pitch. The dot pitch on my 27" presentation monitor, of course, is round the same as any 27" monitor, hence 120hz produces the same type of display as 15khz@60hz does on 27" arcade monitors.
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Not getting scanlines. Exactly what should be on and off? I tried what you said in the first post and it didn't work for me. Could you post copy and paste what's in the INI?
RandyT:
--- Quote from: RayB on July 16, 2008, 10:45:03 am ---Xiau2, I'll agree there's more to it than the lines, but lines are pretty visible as one effect of RGB monitors, followed by the "blobby" pixel shapes, etc. A lot depends also on the focus setting of the monitor.
(Click image to see animation):
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One problem with your demonstration: The scan lines on Turbo are vertical. :) The horizontal lines you see are from the shadow mask, and the fact that they aren't very straight points to an issue there as well.
You just can't see the scan lines in the example due to some pretty significant focus and convergence issues with the monitor.
RandyT
RayB:
oh, I see what you mean. The red green and blue are not aligned.
Xiaou2:
Scan lines are more of an illusion. You usually see a monitor drawing when its
captured by a tv camera. The drawing is so fast, that you wont easily capture it on
camera.
What you see close up, (and even partially at a distance)
is the Shadow mask. Its a mesh screen that seperates the
red, green and blue dots. The lines look wavy... and it took me a while to realize
why. Turns out its an illusion as well. The bright colors bleeding and expanding
past the mask's borders, creates the illusion that there is no line segment in
certain spots. There is also the traditional illusion with bright colors and lines
which fool the brain as well.
What is also interesting... is that each R,g and B pixel area... can be lit up fully,
or in part. Thus, you see examples where 1/4 th the red pixel dot is lit - while the
rest of it is dark.
Interestingly, you would think that the colors should be Red, Yellow, Blue.
But the TV uses green instead! Why? When the green is lit to insane levels...
it changes appearance to yellow. Red can change to bright orange. Deep
dark blue can be very bright light blue. All this without the need for use of
2 colors, as would be needed for painting.
Another thing to consider is how different Dot pitch will make a display look
completely different. I believe dot pitch is the size of the r,g,b sections.
(or all 3 combined into one) Its very clear when you look at your pc monitor
how a small dot pitch changes the look of the output compared to your tube
TV. You can not even grasp a hint of a shadowmask... yet it is there, its just
amazingly small.
Similarly, there is more than likely a big difference in the low res monitors
made at the time of Turbo, than the ones made today. I believe the dot pitch
is smaller now.. and they use a form of scaling to make up the difference. Thus,
todays new low-res monitors would actually show very visible dark lines where
the extra unused pixels were.
The guns themselves may be more accurate.. as well as refined materials and
other technology to reduce bleeding and mixing.
(did you know that to make a menu look transparent on an arcade monitor -
they simply spaced the pixels out in a staggered pattern, like a diagonal mesh.
The mesh was thin and without a nearby pixel to boost its brightness power.. it becomes very dim, and appears to be translucent. )
As for my old monitor not being 100% accurate... thats only part true. Its also
a reality of the way most of us saw them in operation back in the day. Unlike
digital lcds... where when crisp detail is lost its very noticeable... these games were
drawn with the bleeding and mixing in mind. That the best display would
mix things... and even the dusty old display may even improve look.
Notice the pinkish color on the turbo car (pc monitor). Its clearly Not supposed to
look anything like that. However, when its outputted to the arcade monitor...
there is a big blending effect that simply causes a slightly lighter red highlight.
No Simulated lines are going to reproduce that!
Xiaou2:
more pics
1) Shadowcar = Better pic of car
2) Scanline = Shows with long exposure you can capture the drawing line.
However - at speed, your eyes simply can not detect this to any good degree..
else games would have been murder on the eyes.
3) Perfect shadowmask = These shots are VERY hard to accomplish, esp
without a top of the line camera. Another great shot showing the details of the
mask. Probably took 30 bad photos before I got that good one.
4) Magnify = Fooling around with a magnify glass, I held it up to the monitor.
If you look in the background, you can see the differences in looks that the
SHADOWMASK makes as its viewed from a distance. NOT A SCANLINE.