NES on LCD TV problem

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NES on LCD TV problem
by oRBIT2002 on 2007-12-14 (#29490)

When I recently purchased my new Samsung 40" LCD FullHD TV I experienced a problem with my NES. The image is "bouncing" up and down, which looks like just a few pixels, all the time. I experience similar problems on my WII when running Virtual Console NES games. I've read something about that certain tv's can't handle such low resolution (240/256p?) and could cause wierd behaviour, which I suspect is the problem on my tv.
So, how can I fix this?

Is there some external hardware that can be bought that increases the resolution somehow?

I've also tried my old Famicom A/V with the same jumping result.

by kyuusaku on 2007-12-14 (#29492)

The only way to fix it is with a line doubler, and they're usually expensive. I would seriously consider getting another TV or continue to use the old one for progressive consoles if you still have it.

by oRBIT2002 on 2007-12-14 (#29503)

Can't find any linedoublers at all using google.. Are these devices rare?

by kyuusaku on 2007-12-14 (#29505)

They are quite rare. They're also called scan doublers. Here's the idea: http://elm-chan.org/works/sc/report.html

It will turn 480i into 480p which the TV can't mistake for an interlaced signal.

by evildragon on 2007-12-14 (#29509)

Oh, I just borrowed one of those for this: http://www.youtube.com/watch?v=06cd5y5l1Ns

In this case, it was a professional "scaler" with 240p to 540p upscaling, with only 4ms delay, and 540p turns off the scaler in my TV as it's a native scanrate, the Zapper worked.

And yea, the one I borrowed costa couple grand.

by peppers on 2007-12-14 (#29514)

if the onley problem with the old light guns is the video signel the console outputs why dose the Wii use something so inaccurate for there pointer controlls

by evildragon on 2007-12-14 (#29515)

peppers wrote:
if the onley problem with the old light guns is the video signel the console outputs why dose the Wii use something so inaccurate for there pointer controlls

Well it's not the signal.

It's the image processing that TV's introduce. My HDTV by itself, introduces a delay that is approximately 1-2 frames behind, this makes the zapper not function and miss a shot.

The professional scaler I used however only introduces a 4ms delay, and works perfectly fine, as long as the scaler is set to a native mode of the HDTV.

LCD's still failed the test, possibly from native latency. Didn't test a plasma.

by peppers on 2007-12-14 (#29516)

so if you have a tv with a 4ms responce time a zapper will work on its own?

by evildragon on 2007-12-14 (#29518)

peppers wrote:
so if you have a tv with a 4ms responce time a zapper will work on its own?

it should, yes. But I wouldn't trust an LCD.

They don't make CRT HDTV's anymore, but if you can find one that has a mode that the scaler shuts off (usually 540p and 1080i), you might get away with it.

I used the "Radiance" scaler, worth a lot of cash, and my friend wouldn't trust me alone with it..

by bunnyboy on 2007-12-14 (#29521)

peppers wrote:
if the onley problem with the old light guns is the video signel the console outputs why dose the Wii use something so inaccurate for there pointer controlls

The Wii uses absolutely nothing from the TV for its pointer. The sensor bar has 2 IR LEDs and the Wiimote has an IR camera. The LEDs appear as 2 bright dots, which it can use for horiz/vert/rotation processing.

peppers wrote:
so if you have a tv with a 4ms responce time a zapper will work on its own?

The Zapper will only work on a CRT with the correct TV frequency. It should not work on computer screens, LCDs, plasmas, or projectors. You can adjust the Zapper circuit to work on different frequency CRT computer screens, but then the computer TV card may introduce too much of a delay.

by blargg on 2007-12-14 (#29522)

evildragon wrote:
I used the "Radiance" scaler, worth a lot of cash, and my friend wouldn't trust me alone with it..

He was probably worried you'd return a well-executed photoshopped fake back to him.

by evildragon on 2007-12-14 (#29523)

blargg wrote:
evildragon wrote:
I used the "Radiance" scaler, worth a lot of cash, and my friend wouldn't trust me alone with it..

He was probably worried you'd return a well-executed photoshopped fake back to him.

Hey, my photoshopping from my hoaxing days wasn't well executed. It was caught after all.

But anyway, if anyone can borrow the "Lumagen Radiance" scaler, try it on your HDTV with the zapper.

540p is the same 60Hz as 240p, electrically, and as long as the TV doesn't try to process it, it should work, as in my case. I used a Prima HT2778P... (there's two versions of these.. mine doesn't use the red mouse cursor on the OSD)..

by LocalH on 2007-12-14 (#29538)

LCDs et al. don't work with the Zapper because they don't have an electron beam that draws the screen, which is what the Zapper (and other lightguns) detect to tell where you're pointing it. The Wiimote works with any TV because it uses an IR-transmitting "sensor bar" (which is a misnomer because the sensor is in the Wiimote itself) to tell where you're pointing it. Theoretically, the same type of setup could be used with an LCD to have a functioning lightgun.

by evildragon on 2007-12-14 (#29539)

LocalH wrote:
LCDs et al. don't work with the Zapper because they don't have an electron beam that draws the screen, which is what the Zapper (and other lightguns) detect to tell where you're pointing it. The Wiimote works with any TV because it uses an IR-transmitting "sensor bar" (which is a misnomer because the sensor is in the Wiimote itself) to tell where you're pointing it. Theoretically, the same type of setup could be used with an LCD to have a functioning lightgun.

Actually, the zapper just looks for a white square. It either detects white, or not. White = hit, not = miss.

Sega however, I believed with the Enforcer, and the gun on the PlayStation that die hard uses, used the electron gun's beam as a guide.

I know that the delay in an LCD though is far too much for the zapper to detect that white square.

thing is, for my video, my HDTV is a CRT, running at I believe 59.9Hz (but could be 60Hz), and at 540p, it's no different than a regular TV running 240p. No scaler or processing at all. I just needed to use an external scaler that has a dedicated mode for 240p sources to upscale, with as little as a delay as possible.

by peppers on 2007-12-14 (#29541)

To get onto snes for a moment
I assume the lethal enforcer guns work with the electron detection but how bout the super scope it seems a little different is the little box with it just a IR receiver for the wireless or dose it help align the gun?

and also if the zapper just looks for white how dose it know what duck you shot when there is more than one on the screen?

by evildragon on 2007-12-14 (#29544)

peppers wrote:
To get onto snes for a moment
I assume the lethal enforcer guns work with the electron detection but how bout the super scope it seems a little different is the little box with it just a IR receiver for the wireless or dose it help align the gun?

and also if the zapper just looks for white how dose it know what duck you shot when there is more than one on the screen?

because there's more than one frame..

Even though my commodore monitor can't sit still for the flash, you can clearly see one frame has a white square for one duck, then another frame has a seperate square for the other duck...

(don't count on the vertical position of the squares as the CRT lost vertical hold.. but the H position will tell you all)

I will be re-recording that with a TV that works well with the flashing and doesn't lose vertical hold..

by kyuusaku on 2007-12-14 (#29546)

evildragon wrote:
540p is the same 60Hz as 240p, electrically, and as long as the TV doesn't try to process it, it should work, as in my case. I used a Prima HT2778P... (there's two versions of these.. mine doesn't use the red mouse cursor on the OSD)..
What are you talking about now?

540p isn't even a standard. And if it were, it wouldn't necessarily be a ~60Hz field video, only "540p60" would.

HDTVs HAVE to process video if they want to display more than one type of video unlike 525 line SDTVs.

evildragon wrote:
I know that the delay in an LCD though is far too much for the zapper to detect that white square.
And how do you know this? A frame is ~16.67ms and the first random LCD TV I found on Google has 8ms response.

evildragon wrote:
thing is, for my video, my HDTV is a CRT, running at I believe 59.9Hz (but could be 60Hz), and at 540p, it's no different than a regular TV running 240p. No scaler or processing at all. I just needed to use an external scaler that has a dedicated mode for 240p sources to upscale, with as little as a delay as possible.

NTSC's vertical sync frequency is 59.94Hz, but your TV syncs to the video so what you said makes no sense.

Saying "540p", which I assume to mean 480p, is no different than a regular TV running 240p is completely false and I can't think of what you're trying to say for the life of me.

Again, your TV most certainly *does* do scaling and most likely scales video via processing.

by bunnyboy on 2007-12-14 (#29548)

evildragon wrote:
LocalH wrote:
LCDs et al. don't work with the Zapper because they don't have an electron beam that draws the screen, which is what the Zapper (and other lightguns) detect to tell where you're pointing it.

Actually, the zapper just looks for a white square. It either detects white, or not. White = hit, not = miss.

Correct, it is looking for black/white instead of figuring out the horiz/vert position of the cathode ray beam. Guns that do that will usually (always?) have a video pass through cable.

But the white/not detection circuit needs the TV cathode ray tube to strobe at the correct frequency. Taking text from another site there is a band pass filter with a corner frequency of 15KHz. You have to change a resistor to change that filter to 31KHz for computer CRTs. If it just was looking for light or no light, then turning the room lights on and off should work. Just having it be white/black isn't good enough. Someone may already have a test app with half black and half white so you can test that.

by tepples on 2007-12-14 (#29549)

evildragon wrote:
Actually, the zapper just looks for a white square. It either detects white, or not. White = hit, not = miss.

Sega however, I believed with the Enforcer, and the gun on the PlayStation that die hard uses, used the electron gun's beam as a guide.

I seem to remember that one of the Zapper games (Operation Wolf?) used raster timing to find which scanline the gun was aimed at, then scanned white squares across the screen to determine the X coordinate. I calculate that even a 4 ms delay would throw off the aim by 60 lines. Duck Hunt, on the other hand, just cycles whiteness across one target per frame.

See "Light gun" on Wikipedia.

by evildragon on 2007-12-14 (#29550)

kyuusaku, 540p to my TV is "1080i", it doesn't know any different. The manual states that 1080i is the native display rate to the TV.. Service manual states that when in 1080i, the TV will shut down the scaler and allow the input to control the sync directly. Since 540p is electrically the same as 1080i, as is 240p to 480i, it will work the same.

What I'm trying to say is, if it's anything OTHER than 1080i/540p, it's scaled, yes, and that's why the zapper would only register "some shoots", but not all (i do have a vid of that, WITH the zapper in camera too).
http://www.youtube.com/watch?v=N0Z1Lbz96Jg

Instead of going any further with this, I suggest you read up on the aging CRT HDTV's. If this was an LCD or Plasma, you'd be right. But this is a CRT HDTV, and it very well is a different animal in this aspect, and has a "native" mode to which the internal scaler shuts off.

I have asked an HDTV forum to explain this better for me, because I don't know how to explain it very well. WAIT until they respond.
----------------------------------

bunnyboy, i understand what your saying, but how is it people can do a trick like pointing at a light, and the zapper registering a hit? (though that never worked for me, even with one duck on the screen).

by kyuusaku on 2007-12-14 (#29552)

evildragon wrote:
The manual states that 1080i is the native display rate to the TV.. Service manual states that when in 1080i, the TV will shut down the scaler and allow the input to control the sync directly. Since 540p is electrically the same as 1080i, as is 240p to 480i, it will work the same.

This is irrelevant since nothing outputs 540p video and your TV probably isn't even cable of unscaled "540p" progressive scan since 540p isn't a format in use.

evildragon wrote:

What I'm trying to say is, if it's anything OTHER than 1080i/540p, it's scaled, yes, and that's why the zapper would only register "some shoots", but not all (i do have a vid of that, WITH the zapper in camera too).
http://www.youtube.com/watch?v=N0Z1Lbz96Jg

Thanks for the clarification, but it's meaningless. You shouldn't argue what you can't articulate into communicative words. It doesn't matter what you call something, or mean by something, if it's not agreeable to everyone else. So quit making random dubious statements.

evildragon wrote:
Instead of going any further with this, I suggest you read up on the aging CRT HDTV's. If this was an LCD or Plasma, you'd be right. But this is a CRT HDTV, and it very well is a different animal in this aspect, and has a "native" mode to which the internal scaler shuts off.

I don't mind going further. You really don't know what you're talking about, CRT are not a different "animal". If your TV displays 1080i natively, it's a 1125 line display, PERIOD. The only way to have a full screen 525 line picture, which your TV clearly has, is to scale.

by bunnyboy on 2007-12-14 (#29554)

evildragon wrote:
bunnyboy, i understand what your saying, but how is it people can do a trick like pointing at a light, and the zapper registering a hit? (though that never worked for me, even with one duck on the screen).

I have seen it done with some fluorescent lights, which may flicker at the correct frequency. Don't think it would happen with an incandescent. Some games will also check for a sequence like black white black to make sure that isn't happening. I don't think Duck Hunt does that tho.

by kyuusaku on 2007-12-14 (#29555)

Now I can't understand what you're even arguing. For your last two posts you haven't even enlightened me to what I'm wrong about.

If you have a "universal" video processor, it can probably output however many lines you want. What you can't understand is that I never argued against this and there's no reason for you to keep referring back to your Lumagen Radiance because it's irrelevant.

You're even supporting my point again when you say the TV thinks 540p is 1080i. The bottom line is that video has no say in the matter whether the display decides to interlace the video, all it can do is coax TVs with suggestive signals but nothing is guaranteed and I suspect that any digital 1080i TV won't display 540p since it's not an ITU/EBU recommendation, it will assume it's just deviant 1080i.

by evildragon on 2007-12-14 (#29556)

bunnyboy wrote:
evildragon wrote:
bunnyboy, i understand what your saying, but how is it people can do a trick like pointing at a light, and the zapper registering a hit? (though that never worked for me, even with one duck on the screen).

I have seen it done with some fluorescent lights, which may flicker at the correct frequency. Don't think it would happen with an incandescent. Some games will also check for a sequence like black white black to make sure that isn't happening. I don't think Duck Hunt does that tho.

I don't think Duck Hunt does either. I captured a slow vid with 2 ducks.

http://www.youtube.com/watch?v=96BtQx9QwO8