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How do you make an LCD image into a CRT image?

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rCadeGaming:
Ond, great post, but there's a problem with this here:


--- Quote from: Ond on July 15, 2013, 02:40:10 am ---To reduce flicker, CRTs produce only odd-numbered scan lines on the first vertical scan, then even-numbered lines on a second vertical scan.
Each scan is called a field.  Two fields make up a single full frame or image and the process is called interlacing.
--- End quote ---

It should be made clear that CRT's don't display an interlaced picture all the time.  They only do so when fed an interlaced resolution, and arcade games almost always use progressive resolutions, not interlaced.  The same goes for console games prior to the Dreamcast era.

Progressive just means that each frame is drawn completely, all at once, instead of alternating fields of odd and even lines.

Also, interlacing isn't meant to reduce flicker, it's meant to double the amount of lines that can be drawn at a given horizontal scan rate.  For example, a 15kHz CRT (whether it's a 15kHz/CGA arcade monitor or a standard definition TV) can display about 240 lines in progressive (240p), or it can display 480 lines in interlaced (480i).  Either way, each field is only 240 lines; but in 240p each field is a whole frame, whereas in 480i it takes two offset field to create what we perceive as a 480 line frame.  The upside to interlaced is more resolution, the downside is that there are only 30 complete frames per second, instead of the 60 you get with progressive (at 60Hz).  The other downside is that interlaced greatly increases flicker.


--- Quote from: Ond on July 15, 2013, 02:40:10 am ---A PAL Frame consists of 625 scan lines of which 576 lines are visible.  In the PAL standard a CRT produces 50 fields interlaced together, to form 25 frames  of video imaging a second.
--- End quote ---

Ok, this is true.  You also could mention the more common NTSC standard, but neither are relevant here, as arcade games don't stick to either the NTSC or PAL standard.  NTSC is 480i at 60Hz, PAL is 576i at 50Hz.  Most games in MAME run between 224p and 256p at a variety of refresh rates.

nadcraker:

--- Quote from: DickTurpin on July 13, 2013, 11:38:00 am ---You can get a graphics card that has arcade friendly resolutions. That way you can play them in their original resolutions so they look right.

This is what I mean, http://www.arcadeworlduk.com/products/Arcade-VGA-3000.html

A friend has one and the difference is certainly noticeable.

Edit: I am buying one of these next week> It says its guaranteed to run SF4 at 60fps with full detail and I like the look of the ArcadePerfect configuration utility

--- End quote ---

That card sounds awesome, can it be used with a Sony Trinitron Television? Or just an arcade monitor?

rCadeGaming:
It would work with a Trinitron, but there are better alternatives to an ArcadeVGA.  You could also use CRT_Emudriver and a compatible Radeon card:

http://mame.3feetunder.com/windows-ati-crt-emudriver/

An ArcadeVGA is more user friendly, but using CRT_Emudriver is much cheaper, more powerful, and much more flexible if you put in the work.

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