Crt centering device possible?

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Rock Man
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Crt centering device possible?

Post by Rock Man »

Is there a device out there that let's me center my crt display without going into service mode? I ask because we got upscalers, downscalers, and even scanline generators for flat panels. That made me wonder if it's possible a device to center the source exists?

I'll understand if this is not a thing. Worse case scenario I can default to the overscan button. Only trade off is it shrinks my picture too much.
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Fudoh
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Re: Crt centering device possible?

Post by Fudoh »

RGB Shifters are a thing, yes. Usually just horizontal centering though. Getting both axis is rare. Some Extrons did have controls for both horizontal and vertical centering like the RGB 203 rxi.
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buttersoft
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Re: Crt centering device possible?

Post by buttersoft »

There's one on aliexpress that does horizontal and vertical. It's talked about in the h-shift control thread - https://shmups.system11.org/viewtopic.php?f=6&t=67642
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Rock Man
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Re: Crt centering device possible?

Post by Rock Man »

Fudoh wrote:RGB Shifters are a thing, yes. Usually just horizontal centering though. Getting both axis is rare. Some Extrons did have controls for both horizontal and vertical centering like the RGB 203 rxi.
This is going to do wonders for my MiSTer. Sick of always having to ravage settings in the ini file for weak results.
buttersoft wrote:There's one on aliexpress that does horizontal and vertical. It's talked about in the h-shift control thread - https://shmups.system11.org/viewtopic.php?f=6&t=67642
I'll look into it thx
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Guspaz
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Re: Crt centering device possible?

Post by Guspaz »

Just keep in mind that while horizontal shifting can be done with mostly just sync signal trickery, without touching the video signal itself, AFAIK (and maybe somebody can point out if I'm wrong here) vertical shifting can only be done by buffering video data, and running through an ADC and DAC (with all the non-optimal sampling quality loss implied), adding some degree of lag. Only a little lag if they're just time shifting a few scanlines, a bunch of lag if they're lazy and just using a framebuffer.
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Fudoh
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Re: Crt centering device possible?

Post by Fudoh »

no way the Extron 203 does a double conversion. To my understanding the same sync adjustments done to the horizontal signal, can be done to the vertical one just as well. Basically the active 480 lines just get moved up or down inside the 525 line carrier signal, while the front/backporch areas get minimized/maximized.
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