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S-Video + Flat Screen CRT, question about picture


Bixler
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I apologize for making another thread so soon about yet another inane question. I'm using s-video to display my 2600's picture on a flat-screen Toshiba CRT TV. As you can see in this picture,http://imgur.com/bA1At5L, the picture does not fill up the entire screen, and the tiniest bit of it is curved around the upper right-hand corner.

 

Is this normal? Just curious. I realize that the 2600 was not made natively for this kind of TV, so I guess I shouldn't expect anything more. Thanks so much for any help or info you can provide! I love this thing and AA.

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I apologize for making another thread so soon about yet another inane question. I'm using s-video to display my 2600's picture on a flat-screen Toshiba CRT TV. As you can see in this picture,http://imgur.com/bA1At5L, the picture does not fill up the entire screen, and the tiniest bit of it is curved around the upper right-hand corner.

 

Is this normal? Just curious. I realize that the 2600 was not made natively for this kind of TV, so I guess I shouldn't expect anything more. Thanks so much for any help or info you can provide! I love this thing and AA.

 

I'd say your picture is normal. I noticed the curve you have on some of my screens with white or brightest colors. And the picture is not centered, I guess this is a cartridge which hides the hmove artifacts behind a black column.

 

I disagree. The slanted top right corner makes me think something off. I could be wrong but...

 

Does your TV (even though I've only ever seen this sort of option on a PVM before) have an aspect ratio adjust? Manual? Or Software? I don't believe the S-Video mod itself is the problem (again, it could be but unlikely) it seems like a problem with the TV. Can you test it on another screen?

 

Also, are you running the video through a switch box? Or something similar? That could explain it as well...

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I think newer CRT TVs, especially those flat ones, had a lot less overscan, so that would explain the border area.

 

As for the curved edges, I think that has to do with the brightness of the beam in that area affecting the geometry. This is just one of the reasons CRTs are known for their imperfect geometry compared to modern displays. Try lowering the brightness/contrast a little and see if reduces. Or try another game.

 

That being said, these old tvs had all sorts of geometry adjustments you could make, width, height, keystone, etc. Often accessible only through a service menu, or not at all. It's usually not worth the trouble, and hard to get right. Don't even try it if there's no "reset to default" option. Plus, you'll never get perfect convergence (that is red, green, blue signals perfectly lined up on all parts of the screen) or geometry with a CRT.

 

Perfect convergence and gemoetry is one of the few things modern displays do much better than old CRTs.

 

I don't think there's anything wrong with your TV. It looks like you actually got a really good one for classic gaming.

Edited by BillyHW
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The bending - It happens on CRTs. Another issue some especially later and cheaper CRT TVs have is a "ramp change of brightness" or how to describe it...

 

2gy53dx.jpg

 

You can use an LCD but then you lose everything else, no shining phosphor, no super fast response (nanoseconds), no 15 kHz resolution, no razor sharp natural smoothing of the individual pixels, ....

 

Of course a flat CRT screen is somewhat different from authentic rounded CRT screen. If you want real 70s / 80s retro you should go for a rounded screen.

 

 

As for the left border, it suggest using a COMBAT cartridge and setting the screen for this game - this game seems to be filling the screen nicely all around. Also, for the European CRT TVs I use T.J.'s Three S and toggle between 50 and 60 Hz with difficulty switch. Another suitable game to set the CRT screen with.

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I disagree. The slanted top right corner makes me think something off. I could be wrong but...

 

Does your TV (even though I've only ever seen this sort of option on a PVM before) have an aspect ratio adjust? Manual? Or Software? I don't believe the S-Video mod itself is the problem (again, it could be but unlikely) it seems like a problem with the TV. Can you test it on another screen?

 

Also, are you running the video through a switch box? Or something similar? That could explain it as well...

 

I am not using any sort of a switch box. Just white/red audio cables, and an s-video cable. I'm unsure if there is any sort of way to adjust for these kind of settings; I grabbed this TV for free from someone I know. I'll definitely be picking up a much better CRT in the future when I'm out of college.

 

I can try testing it on my dinky HDTV later!

 

I think newer CRT TVs, especially those flat ones, had a lot less overscan, so that would explain the border area.

 

As for the curved edges, I think that has to do with the brightness of the beam in that area affecting the geometry. This is just one of the reasons CRTs are known for their imperfect geometry compared to modern displays. Try lowering the brightness/contrast a little and see if reduces. Or try another game.

 

That being said, these old tvs had all sorts of geometry adjustments you could make, width, height, keystone, etc. Often accessible only through a service menu, or not at all. It's usually not worth the trouble, and hard to get right. Don't even try it if there's no "reset to default" option. Plus, you'll never get perfect convergence (that is red, green, blue signals perfectly lined up on all parts of the screen) or geometry with a CRT.

 

Perfect convergence and gemoetry is one of the few things modern displays do much better than old CRTs.

 

I don't think there's anything wrong with your TV. It looks like you actually got a really good one for classic gaming.

 

Thanks for the insight! Yeah, I don't think I want to try to adjust for those sort of settings (even if I could) for fear of going down a path I couldn't undo and really screwing things up. I mean I barely notice these imperfections as it is, so aiming to go from 95% to 100% might drop me down to 50% satisfaction, or worse.

 

The bending - It happens on CRTs. Another issue some especially later and cheaper CRT TVs have is a "ramp change of brightness" or how to describe it...

 

2gy53dx.jpg

 

You can use an LCD but then you lose everything else, no shining phosphor, no super fast response (nanoseconds), no 15 kHz resolution, no razor sharp natural smoothing of the individual pixels, ....

 

Of course a flat CRT screen is somewhat different from authentic rounded CRT screen. If you want real 70s / 80s retro you should go for a rounded screen.

 

 

As for the left border, it suggest using a COMBAT cartridge and setting the screen for this game - this game seems to be filling the screen nicely all around. Also, for the European CRT TVs I use T.J.'s Three S and toggle between 50 and 60 Hz with difficulty switch. Another suitable game to set the CRT screen with.

 

I'll definitely be picking up a rounded CRT in the future, but for now, alas, this is what I've got. I'll check the brightness and see if that helps at all.

 

Thanks everyone, appreciate the advice as always! :)

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Hello

 

I have the exact same Toshiba 13 CRT and a 4 switch 2600 S video output and mine does not do that at all. Its amazing how good the picture looks on mine. I have thought about trying to find a Sony Trinitron or something but I cant see how the picture could look much better.

 

 

Forrest

 

Hmmm, interesting. Thanks for your input; I'll see if I can figure out what the issue is. I tried composite video, and ran into the same problem as I described above.

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Atari games don't fill up the full screen.

 

Activision is well known for not liking the HMOVE lines, the little black lines you see on the left side of the screen of some games like Ms. Pac-Man:

post-3056-0-65562600-1453135874_thumb.png

 

Those lines are a side affect of repositioning the players (sprites), missile and/or ball. Repositioning is required if you want to show more than just 5 moveable objects onscreen at the same time (yep, there's only 2 sprites, 2 missiles and 1 ball that the Atari can freely move around the screen).

 

Activision wrote their games in such a way that the HMOVE lines show up on every single scanline, which effectively hides them. As a tradeoff, their games look like they're offset to the right. You can clearly see that in Stella:

post-3056-0-61266300-1453134596_thumb.png

 

post-3056-0-06188800-1453134748_thumb.png

 

The bending issue is often caused if the screen is misadjusted, as TVs often are. Photos of TVs can be deceiving, but your set looks like it's too bright. Try lowering the brightness.

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[Fantastic info]

 

Try lowering the brightness.

 

This is all really interesting, thanks for posting! I figured I'd learn something new in this thread. :) I'll adjust the brightness after I'm done working today. I had to turn it up quite a bit when I was playing GTA III on it a ways back; I had trouble making out anything happening in Liberty City. :P

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http://imgur.com/a/KGXgs

 

There is an album I made of a few games - Asteroids, Adventure, Keystone Kapers, River Raid, and the Harmony Encore main screen. Some have that odd bend in the corner (esp. keystone) and others nearly fill up the entire screen; it looks like it varies from game to game...? Not sure why that would be.

 

I did lower the brightness to a more normal level (chopped it in half) but that didn't do anything to alter the picture in the ways I described.

 

Thank you to all who have provided their input! I'll just live with what I have and be happy with what I've got. :)

 

All the best.

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It is normal. In fact I would say those screenshots look excellent. My CRT shows black borders around the VCS screen. Most games were formatted so that the edges and all 160 color pixels and 192 scanlines were within the safe area. NTSC specifies up to 240 scanlines although much of this is outside the safe area. VCS screens were smaller for the most part. This also allowed additional CPU time for calculations.

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I really wouldn't worry about it. I think you've got a good tv for classic gaming. Most of us used tvs of much lower quality than those flatscreen crts back in the 80s. Heck, 80s Zenith only had RF, not even composite.

 

 

Why CRT monitor's image expands when a bright image is displayed?

http://arstechnica.com/civis/viewtopic.php?t=517668

Edited by BillyHW
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There is an album I made of a few games - Asteroids, Adventure, Keystone Kapers, River Raid, and the Harmony Encore main screen. Some have that odd bend in the corner (esp. keystone) and others nearly fill up the entire screen; it looks like it varies from game to game...? Not sure why that would be.

Most consoles have video RAM that the game program updates (ie: the player's sprite is at location 100, 30 and using the image found at memory location $A000). The video chip reads the video RAM to generate the display. RAM was expensive when the Atari was developed so they created TIA, a very unusual video chip that doesn't use video RAM. Instead, TIA has a handful of registers that control what's displayed on a single scanline. TIA has to be updated in real-time, scanline-by-scanline. If it isn't updated the same image will be repeated scanline after scanline.

 

On other systems the video chip decides when to start drawing the screen, so it always starts at the same place. On the Atari, the game program decides when to start updating the video chip, so some games start displaying further up the screen than others, likewise some will end further down the screen.

 

Asteroids is deceptive - they just turned on the background color so it looks like it's using more of the screen than it really is. This is similar to how old computers, like my Commodore VIC-20, have a border color that extends up/down/left/right from the actual image:

post-3056-0-30890900-1453214814_thumb.jpg

 

I did lower the brightness to a more normal level (chopped it in half) but that didn't do anything to alter the picture in the ways I described.

bummer - while that's typically the solution, it isn't always.

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Most consoles have video RAM that the game program updates (ie: the player's sprite is at location 100, 30 and using the image found at memory location $A000). The video chip reads the video RAM to generate the display. RAM was expensive when the Atari was developed so they created TIA, a very unusual video chip that doesn't use video RAM. Instead, TIA has a handful of registers that control what's displayed for just a single scanline. TIA has to be updated in real-time, scanline-by-scanline. If it isn't updated the same image will be repeated scanline after scanline.

 

On other systems the video chip decides when to start drawing the screen, so it always starts at the same place. On the Atari, the game program decides when to start updating the video chip, so some games start displaying further up the screen than others, likewise some will end further down the screen.

 

Asteroids is deceptive - they just turned on the background color so it looks like it's using more of the screen than it really is. This is similar to how old computers, like my Commodore VIC-20, have a border color that extends up/down/left/right from the actual image:

attachicon.gifIMG_6903.jpg

 

bummer - while that's typically the solution, it isn't always.

 

I really appreciate all of the info you've given me, and to those who've reassured me all is well lol. Cheers! :)

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RAM was expensive when the Atari was developed so they created TIA, a very unusual video chip that doesn't use video RAM. Instead, TIA has a handful of registers that control what's displayed on a single scanline. TIA has to be updated in real-time, scanline-by-scanline. If it isn't updated the same image will be repeated scanline after scanline.

 

That must explain why my 2600 slowly looked more and more crazy when I tried playing it on my 60" Plasma.

 

I know thats not the ideal screen to play on! But I just wanted to play some old gavorites on a BIG screen. Some games like Video Olympics, Star Wars: ESB and Freeway played fine... then I tried Space Invaders... and it slowly went to hell... I was afraid I was damaging the system so I turned it off and never tried again!

 

Can what's happening damage a system? If not, great. AT least some games work well with it. It was a blast playing Video Olympics with my son and nephew on that TV... sure it's fuzzy and looks no where near as good as on a CRT, but it's just... funner?

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That must explain why my 2600 slowly looked more and more crazy when I tried playing it on my 60" Plasma.

 

I know thats not the ideal screen to play on! But I just wanted to play some old gavorites on a BIG screen. Some games like Video Olympics, Star Wars: ESB and Freeway played fine... then I tried Space Invaders... and it slowly went to hell... I was afraid I was damaging the system so I turned it off and never tried again!

 

Can what's happening damage a system? If not, great. AT least some games work well with it. It was a blast playing Video Olympics with my son and nephew on that TV... sure it's fuzzy and looks no where near as good as on a CRT, but it's just... funner?

 

The signal the Atari puts out is not 100% to spec. Analog TVs, by their nature, were very forgiving of signal variances. Digital TVs are hit or miss. As an example my 2600 won't work on my HDTV, while my 7800 does - though only in black & white.

 

Additionally, the programs themselves trigger the sync signals required to start a new frame, thus they control many scan lines are generated. Digital Press has a nice list of games with how many scan lines they output. There's a lot of variance, the extremes can even throw off analog sets.

 

262 is the accepted number of scanlines to send, which Space Invaders does. However, as we discovered with Warlords, sometimes the way the program triggers the sync signal the wrong way. I took a quick look at Space Invaders, it does the sync correctly. Something else could be throwing it off.

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