Arcade RGB monitor input signal color temperature correction

Off-topic Chatter
1

Hello! :-)

The following is a question concerning how to adjust the following monitor's default color temperature (≈9300K) down to the more typical ≈6500K industry standard: a legendary Wei-Ya M2929DC-62 arcade monitor factory preset by default to typical arcade saloon bluish ≈9300K lighting, with no way to adjust this parameter via its OSD interface.

A review of this monitor was written up by me, submitted to and published in the now extinct Retroblast arcade site. I still have the original review document submitted back in 2005 to Retroblast's web master, though I cannot remember if I sent him the file in its original “.sxw” StarOffice Writer document or a converted PDF file. Take a look at the photographs published back then, obtained with a cheap Benq 4Mpixel digital camera:



Aaah! What a memories! For the review I plugged the monitor to an Ultimarc's Arcade VGA of that era, which back then didn't supported 25KHz EGA modes. In order to display Super Sprint in its native 350 vertical lines' resolution I was forced to create a custom video mode with a special display tool whose name I do not recall now. The card or its drivers started giving me a hard time trying to sync at 25KHz or thereabouts, though I managed to stabilize a ≈27KHz 350 effective lines mode by increasing both front and back porch width. Seems newer Arcade VGAs do not suffer from such inconveniences, but all of this wasn't as mature back then.

I still have the monitor. Probably less than 20 effective hours of use, no joking! I focused on a big arcade machine project back then but in just a few months certain life changes led me to put all of that off, and it was never done. :((

I've been on a friend's home tonight, discovered an old Sony flat screen CRT TV in great condition. Its box's frame window diagonal measures almost 28", with 27+ viewable inches for the stock CRT. With ≈27.5" viewable area my old 29" LG-Philips tube monitor could fit perfectly. At 110+lbs of tube plus chasis weight hulk… we'll see how it goes, if it actually fits somehow. Got inspired!

With regards to the title question, I've used Tanner Helland convert temperature to RGB article. According to it, at ≈9300K versus 6500K adjusted blue gain would be ≈207 and adjusted green gain ≈222 (221 weighted to 6500K's 254 green level), with red remaining at 255. Tuning these gain values on the graphics card RGB output should lower the Wei-Ya displayed image temperature from ≈9300K to ≈6500K, if I am not mistaken.

Thoughts? Hope Maukka or some other experts see this. :-D

Cheers ^:)

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For your viewing :-D pleasure:

:-)

P.S.: some pictures missing, gonna look for them in my old comp… pictures :facepalm: missing, except for the following two… years later.

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This caught my eye from your old review:

:partying_face:

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Wellp, I got carried away some hours ago being able to open my “.sxw” document in my smartphone with AndrOpen Office.

Yes up to 768 lines in 4:3, but just 576 if you are to keep a 16:9 aspect ratio. However, such a display is better used for other purposes like all sorts of arcade games, classic PC games, emulators or RGB output game consoles with a custom cable. The effective screen resolution is more like half megapixel, though colors look great. :THUMBS-UP:

Wonder if my above temperature correction numbers are right, looks like it to me.

Cheers :-)

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I don’t know if your numbers are “right” or not. For me, the “right” temperature correction is whatever looks best!