CRT Safe Area / Overscan?

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AmateurSegaDev
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CRT Safe Area / Overscan?

Post by AmateurSegaDev » Mon Aug 01, 2022 1:02 am

What's the general accepted "Safe Area" for important game elements when viewing a game on a CRT? I can test against my own CRT (a sample size of one is never ideal), but I would like to know general conventions.

I looked through this thread, and didn't really see a consensus, though I certainly may have missed it:
viewtopic.php?f=22&t=237&start=90

I thought I read somewhere it was in one of the Sega Technical Documents, but I didn't see it there either.

cero
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Re: CRT Safe Area / Overscan?

Post by cero » Mon Aug 01, 2022 5:34 am

It varies, no consensus. Nintendo guidelines from late NES era were two tiles at top and bottom and one tile at left and right.

AmateurSegaDev
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Re: CRT Safe Area / Overscan?

Post by AmateurSegaDev » Tue Aug 02, 2022 4:11 am

Hmm, okay. I guess I'll just roughly follow something like that or eyeball it compared to other games. Thanks for the reply!

Chilly Willy
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Re: CRT Safe Area / Overscan?

Post by Chilly Willy » Sun Aug 07, 2022 6:38 pm

According to the official software standards Sega published with the devkit, you are not to put important info like the score, text, or time in the top or bottom tile rows, and not within the first two or last two tiles of a row.

AmateurSegaDev
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Re: CRT Safe Area / Overscan?

Post by AmateurSegaDev » Tue Aug 09, 2022 1:05 am

Perfect. If that's what Sega recommended, good enough for me.

Thank you Chilly Willy!

I am in constant awe of your knowledge and mastery of the system, it's truly an honor to receive a response from you. :D

Chilly Willy
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Re: CRT Safe Area / Overscan?

Post by Chilly Willy » Tue Aug 09, 2022 9:41 pm

That one I had to look up. I remembered reading it, but not the exact boundaries. Sega did the same thing with the Master System, but it was a bit more restricted as TVs of the time had larger overscan areas due to wildly differing specs of TVs at the time. A Trinitron might show virtually the entire screen, but not an old RCA.

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