NTSC carries a nominal visible picture area of 480 scan lines (240 per interlaced field), but 1970s-80s computers targeting it for display tended to use a smaller area for text/gfx because old TVs extended the picture *outside* the physically visible area to avoid borders, so things would get cropped.
The IBM PC's CGA used 200 scan lines; the Atari defaulted to 192 (but was capable of displaying the full 240 lines per field if you set up a display list with smaller borders!)
Brooke Vibber :blobcatcoffee: /
npub1fk…0q7pw
2024-04-02 16:16:16
Author Public Key
npub1fkq7mhqv478k20403wnz2wsr96dv6h265qsfnrey9tr4eczuk2csf0q7pwPublished at
2024-04-02 16:16:16Event JSON
{
"id": "d4a8ddc2572b822796e2077e9830fb05001ae4260698041ecebc65364a6588d5",
"pubkey": "4d81eddc0caf8f653eaf8ba6253a032e9acd5d5aa020998f242ac75ce05cb2b1",
"created_at": 1712074576,
"kind": 1,
"tags": [
[
"proxy",
"https://bikeshed.vibber.net/users/brooke/statuses/112202519429342367",
"activitypub"
]
],
"content": "NTSC carries a nominal visible picture area of 480 scan lines (240 per interlaced field), but 1970s-80s computers targeting it for display tended to use a smaller area for text/gfx because old TVs extended the picture *outside* the physically visible area to avoid borders, so things would get cropped.\n\nThe IBM PC's CGA used 200 scan lines; the Atari defaulted to 192 (but was capable of displaying the full 240 lines per field if you set up a display list with smaller borders!)",
"sig": "e67df42bde65b5b87e9d3bd3ef7b47aaf77725cb501a7d3d02b7f4ff2c8c5b3b2cb8ff563573f8dfae712b07209ef0e50592e3136dbad06f1661e5e20100cbc3"
}