It's official. I see a rainbow-like effect on every plasma. - Page 18

Don't bother arguing with Zues, he's a troll.

If you ever owned a plasma wiggles, or seen the effect we are talking about, maybe you would have a clue?

OK you guys got me going on this finally with you're unsubstantiated assumptions (hunches if you will). I personally though that the artifact in question sounded like dynamic false contouring (also called "false color") which is a Plasma specific artifact causing color fringing on moving objects. But if you think about it, this cannot be the cause because the color of the fringes/trailing would vary according to content. Yet everyone seems to see only yellow/green trails.

So I went with your assumptions and looked up the ACTUAL current phosphor decay times for PDPs. As you guys have said there is still a wide seperation in decay times even today. Green is the longest, followed by RED and BLUE. So it makes sense that the color fringing/trailing will always be a yellow/green. So the theory sounds plausible.

Now that I agreed with you guys in theory I did some searching to find some actual evidence. It was difficult as the references to phosphor lag and color seperation/perception in CRT or PDP are few and far between.

But I found it

(sorry if already posted but I didn't want to read the entire thread again!)

"One of these artefacts is called the "phosphor lag" and is due to the different time responses of the luminous materials making the different colour components used in the panel. This difference generates a kind of yellowish trail behind and a blue area in front of the bright objects moving on a dark background mainly (or the opposite).

FIG. 1 shows the simulation of such a phosphor lag effect on a natural scene with a movement basically in the vertical direction, where the moving white trouser-leg in front of the black background generates such trail.

On a plasma panel, the red, green and blue luminous elements (also named phosphors while not necessarily having the chemical element P) do not have the same properties because of the chemical properties of each phosphor. In addition the life duration and the brightness are privileged at the expense of behaviour homogeneity. Measurements show that the green phosphor is the slowest, the blue one is the fastest and the red one is mostly in-between. Thus, behind a white object in motion, there is a yellow-green trail, and in front a blue area, as illustrated in FIG. 2. Since the red (R), green (G) and blue (B) cells have different response times, at the front and rear of a moving object like a white block, the concerning pixels are discolored.

In the future, the development of new chemical phosphor powders could avoid such problems by making the green and red phosphors quicker. Nevertheless, today it is not possible by signal processing only to completely suppress this effect but one can try to reduce it."

If you want to read the entire patent it is #7042422

Just so you know, this effect CAN be photographed.

Using a slow shutter speed and panning across contrasty B&W content can reveal differing levels of this on a plasma. Have no experience with other sets.

This would be caused by the camera, not the plasma.

Jon

What is this, a holocaust denier's convention? It's all been explained and documented. If you are like most people and don't see these artifacts, good for you! Don't go looking for them or maybe you will, and don't go thread farting on a thread that doesn't concern you if you don't see them.

Nah, there are no deniers in this thread.

It's just that all of us who see that crap day in and day out on our plasmas have DEFECTIVE eyesight.

Cool. Did you find you're pot of gold at the end of it?

Actually, I've been thinking about this for a while. If indeed what you guys are seeing is green flashes; this may explain why most men do not see... color blindness. A majority of men are to some degree color blind. My son and I have trouble with green. Lucky for me, I calibrate medical displays which for the most part are black and white.

What is more likely:

1. 1% of the population has a defect.
2. 99% of the population has a defect.

So, exactly who is in denial again?

More like 1% of the population is a troll.

Remember that it's also possible the small percentage of the population who see this have extraordinary eyesight. Chuck Yeager reportedly had 20/50 vision (could see at 50' what most people see at 20'). That may be abnormal but it's surely not defective.

Extraordinary implies improvement over the norm.
Somehow this does not sound like an improvement.
Sounds more like 'retina latency' to me.
Isn't 20/50 vision really bad?

Greetings,

Recently purchased a 60inch Pioneer Purevision Plasma, and I'm seeing this plasma rainbow effect too (Plainbow). Here is my experience...

- Areas of bright white adjacent to dark colors sometimes produce perceived flashes of yellow and blue.

- This most commonly occurs after a cut, when the eye changes direction from one actor or object to another, from one area of the screen to another

- Looking around the screen will cause this effect, while it is generally not visible if the eye is focussed in one place

- Black and white video makes it easy to see this phenomena

- I do wear glasses, but can see the effect with our without them

- I have seen the effect on DVDs and TV

I have not found any way to reduce or remove this effect, which I find very distracting.

In considering ways to resolve this, I am interested in the following:

- Could there be any difference in these artifacts when using progressive vs. interlaced video modes.?

- Will higher refresh rate features such as 3:3 pullup/72hz, or upcoming 120hz refresh reduce this problem?

- Does resolution scaling from an upconverting DVD, cable box, or even AV Receiver play any role in this problem?

I would appreciate any suggestions,

John

There is nothing you can do about the plainbows. Really i think you should just sit back and try to enjoy it and see if you are happy with it.

I don't think I can enjoy viewing with plainbows like this. Do you mean to say that all Plasmas will have this problem? I will exchange it if that is what is necessary.

I went to the store and could not see Plainbows on any of their Plasmas (even the same model I have), in any of their light or dark viewing rooms. One difference is that they were using a satellite video feed for their in store demo video.

Could there be a problem coming from the DVD Player, Cable Box, or AV Receiver?

When I switched from DVI/HDMI to Component Video, the color range seemed to improve dramatically, and I couldn't see any plainbows. There is no scaling going on in this case either, so I can't blame the upsampling features.

I still don't see any plainbows when viewing video from a PC on the Plasma. This makes me wonder if the cause of this effect is 24 or 30 fps video. The 60hz VGA output looks better, but I can't get a Cablecard in my PC, AFAIK.

I'm going to switch the cable box to component video and see if that makes any difference. After that, I will try running video sources directly to the TV, bypassing the amplifier's HDMI switching. The last thing that I can explore is whether the scaler in another amplifier here will produce video without these annoying plainbow flashes.

Rainbows have been used to describe many gremlins. Unfortunatelly the term is so overused that it no longer means much. In plasmas it is used to describe the effect caused by differernt decay times of the phosphors. Whatever you are seeing is not that. The fact that it occurs only on certain signals eliminates phosphor decay as your problem.
Not sure what you mean when you say; "When I switched from DVI/HDMI to Component Video, the color range seemed to improve dramatically, and I couldn't see any plainbows."

HDMI/DVI are the purest connections you can use, so I am at a loss as to why when you switched to component "the color range" improved dramatically.

Can you be more specific defining "color range"?

The fact you did not see this effect at the store with the same set tells me something else on your hook up is the cause of this problem. It could also be a defective HDMI port on the set, I suppose.

You're a funny guy, Chris. Really.

Another model wont help. Or going from component etc. Remember you see this on black and white material. A different brand could be less prone to the effect, but if you read this thread both pannys, pios, vizios, etc have the problem.


Same with me, i never see the plainbows in stores even with pretty dark environment. Same with dlp, never in stores, and i question those that say they see it in stores with any amount of light.



NO!


Again, black and white proves color and connections is not the problem. I think, just a guess, is how plasma lights up. You should be able to see the effect with just a snow image, nothing hooked up to it.



Interesting.


I hate to say it, it should not make a difference.

I just purchased a Panasonic 50in plasma and experience the same thing. Using comcast cable and DVD's via component. My wife thinks I'm crazy.

I have the th-42ph9uk and I am defiantly seeing yellow flashes. I can't look directly at them there always toward the side of the screen in my peripheral vision. I notice it quite a bit playing Gears of War. Occationaly I see it on TV broadcasts and movies but not enough to cause concern.

I also see this effect.

Anybody want to buy a PDP-5070 with less than 100 hours on it? *sigh*

Doesn't work for me.

FWIW, I saw the yellow flashes on the 50" 700U over the weekend at Tweeter.

I am highly sensitive to temporal artifacts though - rainbows drive me nuts on DLPs.


I have seen green flashes on older Pioneer Elites.

I can join this group now. I see yellow trails on my Samsung 5054. I'm very upset about this as I got this plasma to escape DLP rainbows. Is there any way to get around this yet?

Ugh, I just checked this thread out for the first time in over a year. This was the reason I didn't buy a plasma over 2 years ago, cause I too noticed this yellow flashing immediately. I was hoping by now it would be resolved.

Is there any reason to think that 1080p Plasma would be different? Maybe the extra pixels are controlled or fired differently? Or maybe the Samsungs with the higher glare filters get rid of some of the flash? Some people wrote that they see it less on the Samsung. (I only have the lesser filter version)

Plasma is far away the best looking panel on the market... There has GOT to be some way we can conquer this and enjoy them. People may laugh, but the yellow flashes are REAL to some of us.

Id also be interested to know if the 1080p sets get rid of the trails. Maybe because their are double the pixels the trails and flashes will be less noticable. Im hoping the new Pioneer 8g don't have this problem at all.

I also see something similar to this poster on a Pioneer Pro-FHD1, and on all plasmas that I have seen, to some degree.

Can someone post a link to how Plasmas create their intensities? When they display an intensity, does the current in the gas just go up and down to match, or do they quickly turn the plasma off and on in pulses to get the various intensities?

On the Pioneer, I could see sparkles in pure almost-white scenes if I moved my eyes. It was like dancing fireflies in regions as my eye moved. I could also see definite static dithering, as well as dynamic flashes in the dark grays. Its like plasma can't really display anything other than on or off, and they just dither the pattern and the intensity versus time to give us the different colors and intensities.

This is not a problem for me at normal viewing distance. However, when close up, it would be a killer. I think we could understand this phenomena better if a Plasma expert could explain how the cells work.