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I was fiddling around with Meka and Snes9X and I found the TV mode effects in their graphics enhancement options. It does look like a TV when you sit far away but it still doesn't do it pefectly. Someone told me along time ago that television sets have an electron gun that beams light at certain intensities to a large LCD sheet beneath the glass on the television. This LCD sheet is a matrix of Red, Green, and Blue stripes that are positioned like a chain-linked fence (sort of). You can really see this if you turn the brightness on your TV way, way up and put your eye like less than an inch from it. Close one eye, focus really hard, and you'll see them. The strips are like this...




R = Red


G = Green


B = Blue


* = black





[*][R][G][B][*]


[B][*][R][G][B]


[*][R][G][B][*]

So, for every Red, Green, and Blue stripe, there's a black stripe. So see, it's not the doubled displays or the deep scanlines that make the TV diplay but correctly simulating those stripes (I hope). I assume that if you do so the graphics dithering, scanlines, and images will naturally display like a real Television set. Am I right or wrong?

Chris :o)

[snip]

LCD sheets?(!)

anyways i think you are talking about the little breaks between phospher dots of the same colour. maybe they might add some of the actual picture effect, but i dont know how you would simulate it, as they are quite tiny, and maynot be replicatable on small resolutions? i dont think the chain link idea is standard for all tv's either, ive seen plain vertical strips as well as what you mention. only the part of the phospher that gets hit lights up (so what are the little black breaks for? i dont know, but i can only hope someone else does).
personally i dont think they are worth considering, but then again, i guess ill have to check it out for my self :)

on other notes, i think how an average low res console displays its image is by letting the tv draw all its odd(even?) fields(first half of the interlaced lines) and then 'resets the sync signal' (?) and redraws ontop of the previously drawn fields (ie tv only ever draws the odd fields, never the even etc). so you horizontal lines that actualy do get updated 50/60 times a sec, and not 25/30. this would account for 'scanlines' as well.

investigations with a video camera looking at tv seems to confirm this sort of.. regular interlaced broadcast shows a vertical gradiant of dimness (does that make any sense?) while my sms2 shows the dimning gradiant as well as a lighter gradiant which i did not see on broadcast - i assume that because the odd fields are getting scanned 'twice as much as normal' they get the chance to glow brighter??

i also calculated that it ran at 49.696969(or was that 50.30303030?) etc frames a second rather than a steady 50 that regualr broadcast gave

please feel free to tell me im confused or correct. either one would be nice!

Author	Message
Consolemu Guest	Real Televison Simulation Posted: Mon May 29, 2000 5:15 am
Consolemu Guest	I was fiddling around with Meka and Snes9X and I found the TV mode effects in their graphics enhancement options. It does look like a TV when you sit far away but it still doesn't do it pefectly. Someone told me along time ago that television sets have an electron gun that beams light at certain intensities to a large LCD sheet beneath the glass on the television. This LCD sheet is a matrix of Red, Green, and Blue stripes that are positioned like a chain-linked fence (sort of). You can really see this if you turn the brightness on your TV way, way up and put your eye like less than an inch from it. Close one eye, focus really hard, and you'll see them. The strips are like this... `R = Red G = Green B = Blue * = black [][R][G][B][] [B][][R][G][B] [][R][G][B][*]` So, for every Red, Green, and Blue stripe, there's a black stripe. So see, it's not the doubled displays or the deep scanlines that make the TV diplay but correctly simulating those stripes (I hope). I assume that if you do so the graphics dithering, scanlines, and images will naturally display like a real Television set. Am I right or wrong? Chris :o)

Limbs a Flyin' Guest	Posted: Tue May 30, 2000 3:57 pm
Limbs a Flyin' Guest	[snip] LCD sheets?(!) anyways i think you are talking about the little breaks between phospher dots of the same colour. maybe they might add some of the actual picture effect, but i dont know how you would simulate it, as they are quite tiny, and maynot be replicatable on small resolutions? i dont think the chain link idea is standard for all tv's either, ive seen plain vertical strips as well as what you mention. only the part of the phospher that gets hit lights up (so what are the little black breaks for? i dont know, but i can only hope someone else does). personally i dont think they are worth considering, but then again, i guess ill have to check it out for my self :) on other notes, i think how an average low res console displays its image is by letting the tv draw all its odd(even?) fields(first half of the interlaced lines) and then 'resets the sync signal' (?) and redraws ontop of the previously drawn fields (ie tv only ever draws the odd fields, never the even etc). so you horizontal lines that actualy do get updated 50/60 times a sec, and not 25/30. this would account for 'scanlines' as well. investigations with a video camera looking at tv seems to confirm this sort of.. regular interlaced broadcast shows a vertical gradiant of dimness (does that make any sense?) while my sms2 shows the dimning gradiant as well as a lighter gradiant which i did not see on broadcast - i assume that because the odd fields are getting scanned 'twice as much as normal' they get the chance to glow brighter?? i also calculated that it ran at 49.696969(or was that 50.30303030?) etc frames a second rather than a steady 50 that regualr broadcast gave please feel free to tell me im confused or correct. either one would be nice!

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