This question was previously posted in the "Flat Panel General & New FP Tech" section of the forum:

I have a 8G Pioneer plasma. In certain games, fast movement (spinning on the spot) can often result in a double image. Maybe there is a bit of blur but I often see a double image. Panning while viewing white text against a black background is a good example - I see a ghost image of the text. I heard this double image may be due to glass reflection inside the tv. Is this correct? Is it an inherent limitation of plasma or will this be sorted out in future plasmas?

Note: I do not really see blurring in the above example but rather a distinct ghost image. Nor do I believe this is phosphor lag as there is no trial between the original image and its ghost.

Here is a link to the original thread:
http://www.avsforum.com/avs-vb/showthread.php?t=1029808

hmmmm.....i have been reading the forum for over 17 months, don't recall any posts on ghost-imaging...people do see color trails (comet effect)


This question was previously posted in the "Flat Panel General & New FP Tech" section of the forum:

I have a 8G Pioneer plasma. In certain games, fast movement (spinning on the spot) can often result in a double image. Maybe there is a bit of blur but I often see a double image. Panning while viewing white text against a black background is a good example - I see a ghost image of the text. I heard this double image may be due to glass reflection inside the tv. Is this correct? Is it an inherent limitation of plasma or will this be sorted out in future plasmas?

Note: I do not really see blurring in the above example but rather a distinct ghost image. Nor do I believe this is phosphor lag as there is no trial between the original image and its ghost.

Do you have a Xbox 360 and Bioshock? You should be able to see ghosting in that gaming - see the discussion in the original thread. Note: only one other person has tried out the Bioshock test so far and claimed NOT to see what I am seeing.... If others want to try the same test I would be very keen to hear from you.

Never mind, i was having the same thing as the OT, but then i read this

All the games that you mentioned are 30fps, so this could easily be the problem, which would make it a source issue, not a issue with the Kuro. I see this same low framerate Judder on my Panasonic plasma, and my LCD PC monitor when showing low framerate games. I describe it as Judder because it breaks up the smooth motion of the video, which is what you are describing above. You are probably very sensitive to low framerates like many of us are. Get Call of Duty 4 and give it a try, it should get rid of the blur you are seeing.

This has nothing to do with phosphor decay, it is just a low framerate of a particular game showing it's limitations during fast motion. (which is why Infinity Ward who developed CoD4 refuses to do anything in a game that reduces the framerate below 60fps, anything less takes you out of the experience)

and i give COD4 a tried and it Amazingly smooth. i can read the signs on the streets while panning while looking around really fast, amazing, now i see what they are talking about the Plasma response. (i got my plasma today) i used to game on lcd btw, i don´t see myself going back now! lol

OT, give COD4 a try and let us know if you are experiencing on that game as well, i guess this is because the games you are trying are 30FPS as Pendragon said.

There are three kinds of double-image that you'll see on a Plasma.

The first is when you send 30fps material to the screen – doesn't matter what the source is. If you send 30fps to a 60hz screen it always ends up in a double-image. This is not exclusive to Plasmas though, affects LCD, CRT etc as well.

The second is ‘phosphor lag’ which is a double-image caused by the blue phosphors responding quicker than the rest, causing the image to split up more the faster the movement is across the screen:

http://sr-388.net/images/av/phosphor-lag.jpg

This seems to be inherent to Plasma technology itself, though most people apparently can't see it.

The third is a double-image that appears at wide angles due to internal reflections on the screen. This is not an issue with Pioneers as they eliminated the separate layer that causes it.

you can see the same problem with crt only difference is on plasma the image is greenish.

you can see the same problem with crt only difference is on plasma the image is greenish.
It's not the same problem at all. With a Plasma, the image actually separates in two, and you can often see bright blue/green flashes.

With a CRT, all you get are dark green trails behind bright objects moving over dark backgrounds. You don't get any flashes and it's not visible in bright scenes. (it is with Plasmas)

http://sr-388.net/images/av/phosphor-crt.jpg

Andrew,

Thanks for posting this great picture (and for the rest of your input). This is exactly the sort of ghosting I am seeing - a distinct ghost image without a trial between the original and the ghost. (Note: the ghosts I have seen in Bioshock have reduced brightness compared to the original but I believe their color is otherwise the same as the original.)

There are three kinds of double-image that you'll see on a Plasma.

The first is when you send 30fps material to the screen – doesn't matter what the source is. If you send 30fps to a 60hz screen it always ends up in a double-image. This is not exclusive to Plasmas though, affects LCD, CRT etc as well.

Why does this first type of ghosting occur? Is the ghost just a result of slow phosphor decay from the prior frame? (Is there any technology that does not have this issue?)

The second is ‘phosphor lag’ which is a double-image caused by the blue phosphors responding quicker than the rest, causing the image to split up more the faster the movement is across the screen:

http://sr-388.net/images/av/phosphor-lag.jpg

This seems to be inherent to Plasma technology itself, though most people apparently can't see it.


Is this an image from Forza 2 running at 60fps? (I take it the car is spinning to the driver's left in this picture?) So I suppose the question is: what are the prospects for future plasmas to have different colored phosphors that all respond at the same rate? It will be interesting to see if the 9G Pioneer plasmas are better in this regard. Maybe we'll have to wait for the infinite contrast models which I imagine would have to have vastly improved response times.

The third is a double-image that appears at wide angles due to internal reflections on the screen. This is not an issue with Pioneers as they eliminated the separate layer that causes it.

Andrew,

Thanks for posting this great picture (and for the rest of your input). This is exactly the sort of ghosting I am seeing - a distinct ghost image without a trial between the original and the ghost. (Note: the ghosts I have seen in Bioshock have reduced brightness compared to the original but I believe their color is otherwise the same as the original.)



Why does this first type of ghosting occur? Is the ghost just a result of slow phosphor decay from the prior frame? (Is there any technology that does not have this issue?)



Is this an image from Forza 2 running at 60fps? (I take it the car is spinning to the driver's left in this picture?) So I suppose the question is: what are the prospects for future plasmas to have different colored phosphors that all respond at the same rate? It will be interesting to see if the 9G Pioneer plasmas are better in this regard. Maybe we'll have to wait for the infinite contrast models which I imagine would have to have vastly improved response times.
i see this on 30Fps games, but on 60fps games it´s awesome smooth.
i think some explained why this happen on the other thread.

basically you will see this on any 30fps game while on 60fps you shouldn´t.

If it's the 30fps double-image, then it will be the same colour, if it's phosphor lag then it'll be a very obvious bright blue/green separation and can show up regardless of the framerate. They look the same other than that though.

I used the Forza 2 demo for the example pictures as it's running at 60fps. This avoids the 30fps double-image but still shows off the effects of phosphor lag.

I'm not really sure what causes the double-image with 30fps sources, I just know that it's been visible on every progressive display I've ever used. (I'm not sure if it shows up on interlaced CRTs or not, it's been too long since I used one with games, where it's most obvious)

It sounds to me like it's the 30fps double-image that you're seeing rather than phosphor lag, so it'll show up no matter what screen you're using. If you have interpolation options on your display (I believe the Pioneer's have a ‘smooth’ mode) then you could try and see if that helps reduce/eliminate it, but that brings its own problems.

I've read someone seen major green trailing effect with the game Gears of war. Someone posted a video on it. Their was alot of talk of this in the rainbow thread.

i see this on 30Fps games, but on 60fps games it´s awesome smooth.
i think some explained why this happen on the other thread.

basically you will see this on any 30fps game while on 60fps you shouldn´t.

I have Forza 2 which is 60fps. I haven't seen ghosting in this game but I haven't really played it much yet. I had another quick look just now - I was looking for the part of the game that andrewfee used to produce his pictures but was not able to find it. I have to do some more searching around.

I'll also get CoD4 at some stage and see how that goes.

I'm not really sure what causes the double-image with 30fps sources, I just know that it's been visible on every progressive display I've ever used. (I'm not sure if it shows up on interlaced CRTs or not, it's been too long since I used one with games, where it's most obvious)

It does occur on my CRT as well. Initially I thought it was due to the interlaced nature of CRTs but I'm not sure.

It sounds to me like it's the 30fps double-image that you're seeing rather than phosphor lag, so it'll show up no matter what screen you're using. If you have interpolation options on your display (I believe the Pioneer's have a ‘smooth’ mode) then you could try and see if that helps reduce/eliminate it, but that brings its own problems.

The smooth option doesn't seem to help (at least not on Bioshock).

I've read someone seen major green trailing effect with the game Gears of war. Someone posted a video on it. Their was alot of talk of this in the rainbow thread.

The 8G Pioneers seem to be much better than the plasma used in that video. I've certainly not experienced anything like what was shown in that video on my Pioneer when playing Gears.

Given that ghosting can occur in 30fps games, its probably also affecting 24fps movies (even if they're played at 72Hz) :(

I have Forza 2 which is 60fps. I haven't seen ghosting in this game but I haven't really played it much yet. I had another quick look just now - I was looking for the part of the game that andrewfee used to produce his pictures but was not able to find it. I have to do some more searching around.
It's just the car select screen with the car spinning around as quick as it can. (using the right stick)

As the camera had to be set to a high shutter speed to capture it properly, it looks darker than it actually does in the game.

It's just the car select screen with the car spinning around as quick as it can. (using the right stick)

As the camera had to be set to a high shutter speed to capture it properly, it looks darker than it actually does in the game.

OK I just tried this out quickly on my Kuro. With certain cars I do see a double image. One example was a darkish red car with black water nozzles on its bonnet. Spinning the car I could see a ghost of the nozzles. (I haven't noticed any color separation so far.)

OK I just tried this out quickly on my Kuro. With certain cars I do see a double image. One example was a darkish red car with black water nozzles on its bonnet. Spinning the car I could see a ghost of the nozzles. (I haven't noticed any color separation so far.)
Well Forza 2 is a 60fps game, so any double-image you see is phosphor lag, assuming you don't have Smooth enabled or any of the noise reduction features that is. I guess you just don't see it in colour for some reason? :confused:

Well Forza 2 is a 60fps game, so any double-image you see is phosphor lag,
If I'm understanding you correctly you're saying ghosting with 60fps material is always a result of phosphor lag, ie, different colored phosphors reacting at different speeds. You mentioned before you weren't certain why ghosting occurs with 30fps material. I would of thought the same mechanism is at work for both 30fps and 60fps...

assuming you don't have Smooth enabled or any of the noise reduction features that is.
Smooth is not being used and all noise reduction is off.

I guess you just don't see it in colour for some reason? :confused:
No - I had another look just now and though it is easy for me to see double images, I don't see any difference in color. You can see a difference in color without using a camera?

Remember, in order to get a 30fps game to work on a 60hz TV, you have to double the frames repeating each frame, while this works for movies just fine (movies limit movement in any given scene, but it can be seen on fast action as well) games tend to show it's flaws much more easily, due to the much faster motion involved with any given game. You might be able to minimize this effect with a 120hz LCD with motion interloping activated, but that will also add it's own flaws that you might find even worse.

This has nothing to do with fringing, which shows green trails with 60fps and a green double image for 30fps, and if you can't see the green trails, then consider yourself lucky and don't go looking for them, once you see them you can't unsee them. (those double images your seeing will start to have a green tint to them once you know what fringing looks like on your plasma and are looking for it)