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Discussion Starter · #1 ·
Finally, today, I saw what everyone means by rainbows, first on a Yamaha DLP projector, then on the Samsung 43" DLP RPTV.


The salesman told me to move my head back and forth quickly, or move my eyes quickly back and forth, and not focus on the screen.


They remind me of those laser-created plastic see-through things that you could look put on your window and see "rainbows" whenever you looked at lights.


Actually, they're not "rainbows," to me -- just a breaking up into red and green components (blue, too, I guess, but the blue is harder to see).


It's almost kind of a subliminal thing -- you "think" you see them, like a brief after-image. A great example was Frodo throwing the ring in the air when he falls on the floor of the Inn they were supposed to meet Gandalf at -- Lord of the Rings: Fellowship of the Ring Extended Edition Disk 1 Chapter 15 at time point 01:01:46.


Not as much fun as LSD tracers.


(just kidding!)


So ... maybe I will keep the Sony GW -- don't know how distracting or annoying these chromatic blips would be over time. I know, you warned me not to go looking for these things. But God told Adam not to eat the fruit from the tree of the knowledge of good and evil, and look how much good that did (only in this case, it wasn't my wife telling me to look for rainbows).
 

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I'm awating a 507W PB set and have not seen any rainbows during my evaluations.


One possible solution would be to not "move one's head back and forth quickly, or move one's eyes back and forth without focusing on the screen." If you look for any problem long enough or hard enough, you'll always think you have found it.


If rainbows are distracting or annoying to someone during extended "normal viewing" (not doing the things above or laying on the floor looking up at the screen), then they constitute a real problem.
 

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Discussion Starter · #3 ·
Quote:
Originally posted by jeffmcclan
I'm awating a 507W PB set and have not seen any rainbows during my evaluations.


One possible solution would be to not "move one's head back and forth quickly, or move one's eyes back and forth without focusing on the screen." If you look for any problem long enough or hard enough, you'll always think you have found it.


If rainbows are distracting or annoying to someone during extended "normal viewing" (not doing the things above or laying on the floor looking up at the screen), then they constitute a real problem.
I think the larger issue is the fact that this "rainbowing" is always there, just usually not noticed -- like the flickering of fluorescent lights or CRT computer monitors. For most people, its presence means nothing -- even seeing them occasionally may mean nothing. But the eye/brain sees them and registers them, even if the viewer doesn't notice them. And some people may actually experience fatigue from this and not be able to explain why. Some on this site have suggested that they have noticed headaches or eye fatigue from long viewing of this DLP TV that did not seem to be the case with other televisions. Maybe they subconsciously thought about the rainbows and came to believe that they were getting headaches or eye fatigue. Or maybe this is a real physiological problem for them, much like some epileptics can react to strobe lights.
 

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Quote:
Originally posted by jeffmcclan
One possible solution would be to not "move one's head back and forth quickly, or move one's eyes back and forth without focusing on the screen." If you look for any problem long enough or hard enough, you'll always think you have found it.

That was my thought when trying to live with my 507. I spent 4 weeks trying to limit my eye movements. I don't think it is possible - especially on 16:9 stuff. With a big screen I focus my attention on different parts of the screen and this would invariably cause me to see rainbows with the right screen content. Get some action on the screen - and the tendancy to follow moving objects and the eye movement ( and rainbows) are worse.


My personality is such that once something bugs me, I can't get it out of my mind. Trying to live with the rainbows was just too much for me.

If you see rainbows, I don't think limiting eye movement is really an answer.
 

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I had a similar experience to hrpull. I had the 507 in my apartment for 3 weeks and decided that I cannot live with the set. It took me a week to start seeing rainbows...but once I did, I could not make them go away. At first, I thought I could live with them, but as time went by they bothered me to the point that I had to return the set.
 

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The rainbows have annoyed me with FP units at work for some time. Depening on where I sit , I can see rainbows out of the corner of my eyes. This is especially annoying during a "death by Powerpoint" marathon session. I couldn't help but notice them on the 507. The picture is decent but I would be forever bugged by them. Once one is sensitive to them, I think they will not go away as a nuisance.
 

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Quote:
Not as much fun as LSD tracers.


(just kidding!)
You know, that's the best way to describe it that I've heard yet...if I remember correctly.
 

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This set really IS amazing. It's revealing deeply held beliefs and mental habits of those who view it. I plan to RELAX and enjoy mine. ;)
 

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Quote:
Originally posted by jeffmcclan
I'm awating a 507W PB set and have not seen any rainbows during my evaluations.


One possible solution would be to not "move one's head back and forth quickly, or move one's eyes back and forth without focusing on the screen." If you look for any problem long enough or hard enough, you'll always think you have found it.


If rainbows are distracting or annoying to someone during extended "normal viewing" (not doing the things above or laying on the floor looking up at the screen), then they constitute a real problem.
That was my opinion until I received my set.....I absolutly did not want to see rainbows, didn't want to look for them or even think about them but they found me. I was watching Alias Sunday night, a bunch of people in suits were standing in a room and it was very bright behind them. I was reading a magazine so I was looking between the screen ans the magazine repeatedly when I saw a rainbow burst from the sliver of white showing between somebodys legs on the screen......dark pants showing a white background behind them. Later that night I was using the THX setup portion on the Monsters Inc DVD, it's got a section where they display a thin white circle on a black background.....everytime I'd look from the screen to the remote control I'd get a rainbow burst from the circle. I wanted so badly to not see these things. I figured everybody that was seeing them were trying too hard or were nit picky......I was naive to assume that these flaws would not be present on a production ready device......oh well. It's the Terrible blacks that are bothering me at this point.
 

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Discussion Starter · #10 ·
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Originally posted by Supertoyz
That was my opinion until I received my set.....I absolutly did not want to see rainbows, didn't want to look for them or even think about them but they found me. I was watching Alias Sunday night, a bunch of people in suits were standing in a room and it was very bright behind them. I was reading a magazine so I was looking between the screen ans the magazine repeatedly when I saw a rainbow burst from the sliver of white showing between somebodys legs on the screen......dark pants showing a white background behind them. Later that night I was using the THX setup portion on the Monsters Inc DVD, it's got a section where they display a thin white circle on a black background.....everytime I'd look from the screen to the remote control I'd get a rainbow burst from the circle. I wanted so badly to not see these things. I figured everybody that was seeing them were trying too hard or were nit picky......I was naive to assume that these flaws would not be present on a production ready device......oh well. It's the Terrible blacks that are bothering me at this point.
I wouldn't call it a "flaw." It's the nature of the beast, i.e., a single-chip DLP projector with a color wheel. It's possible that a faster color wheel would reduce the rainbowing, but that may not be possible -- i.e., the speed of the wheel might be tied somehow to the material that's being displayed, e.g., 480i/480p material might need a certain speed color wheel or you'll get an effect like wheel spokes moving backwards as happens in movies. Or, going to a much-more-expensive 3-chip DLP system might reduce rainbows. Just guessing. People who know the technology of DLP can answer this. The salesperson said ALL DLP projectors (front or rear) that he'd seen do this "rainbowing" to some extent. He felt it would be much more pronounced on the front-projector (plus, it was the older chip -- though that may not be an issue for rainbowing, only for contrast and black levels), and said he hadn't seen rainbows on the 43" Samsung. So we then went into the room with the Samsung and, lo and behold, he now could see rainbows on the 43" Samsung when we looked at LOTR:FOTR extended edition to catch rainbows in the flames at the Inn.


We didn't really see them in the flames but DID see them every time we glanced away -- just like you are talking about -- it's like an after-image thing. You think "Did I see that?" -- and if you didn't know about rainbows, you'd think it was your imagination. Until Frodo flipped the ring in the air. Voila! BIG RAINBOWS!! The glint off the gold broke into distinct reds and greens, no imagination needed.


(FYI, I clued the salesman into the free movie ticket that was in his DVD set that he didn't know about, and to the "easter egg" on disk one -- go to the chapter/scene list, go to the page with chapter 27, go down with your button/arrow one past chapter 27 and a "ring" will appear on the left at the bottom. Click on it, and you'll see a somewhat crude MTV video of the council to decide what to do with the ring. Do the same thing on disk 2 (after chapter 47, I think?) and you'll see a tower shape on the bottom RIGHT of the disk. Click on that and you'll see the TWO TOWERS trailer that was shown in the theaters.)


Yep, just like LSD tracers (sort of -- not kidding this time).
 

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I saw rainbows too last night when I moved my eyes quickly off the screen during the credits (white letters with black background) at the end of a movie. I don't think it would be a problem, I don't like to watch credits anyway. I was trying to see if there were internal reflections with light objects (the letters) on black background. There were none.
 

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Here's two other things I saw that I was hoping people could refute or verify. Also during Alias when Sydney was talking to her mother, they were showing a closeup of Sydney's face while she was talking to her mother who is by the way on the other side of a glass wall. Next to Sydneys face I could see the ghost image of her mothers face next to it. Since they were facing each other you shouldn't see a refelction of the mothers face looking at you unless it was an actual reflection of her face off of the glass wall....in that case it would actually be correct but I've never seen this before on the show and they have had similiar scenes many times. The next problem I noticed was last night during the King of Queens. They were scanning their living room repeatedly and it appeared to me that the object in the middle of the room stayed focused but the material on the left and right side of the screen became wavy.......like looking through a Coke bottle. Once the panning stopped the image looked fine.....they would pan again and the sides of the image became goofy again. I wasn't sure if it was me or not, anybody else see this before?
 

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So how bad and or noticeable are these rainbows? Since I imagine I'll be doing a lot of glancing around the screen when I play games I imagine that I'll see some.


Are these problems inherent in front projectors too, becuase I swear I saw a rainbow on my friends Runco FP but it was so quick I might have just been imagining it.


Another thing, has anyone yet experianced the eye fatigue that many people are talking about?
 

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Discussion Starter · #14 ·
Quote:
Originally posted by TogaAssasin
So how bad and or noticeable are these rainbows? Since I imagine I'll be doing a lot of glancing around the screen when I play games I imagine that I'll see some.


Are these problems inherent in front projectors too, becuase I swear I saw a rainbow on my friends Runco FP but it was so quick I might have just been imagining it.


Another thing, has anyone yet experianced the eye fatigue that many people are talking about?
If the Runco is single-chip DLP, rather than LCD, then it probably has a rainbow potential, due to the color wheel. Read how DLP works at:

http://www.plasma.com/classroom/what_is_dlp.htm


Also, click on the link for "Check out the DLP Video Projector Demo by Texas Instruments" to see a great animated explanation of DLP (which also shows why 3-chip DLP prism systems shouldn't have a rainbow problem, i.e., no color wheel).


Also, see http://www.dlp.com


As I experienced, you may not see it until you're told how to see it (i.e., move your head back and forth quickly, without focusing on the image), but once you see it, you'll realize that you have been seeing flashes of it whenever you've looked away from the screen or moved your eyes rapidly, but you didn't at the time recognize what that brief "did I imagine this?" sort of red-green flash that appeared in your mind really was.


The following link has been posted elsewhere before, but it has a good brief discussion of DLP "rainbows" and how they're caused. They can indeed be diminished by increasing the speed (real -- or effectively, i.e., by doubling the red, green, and blue segments) of the color wheel.

http://www.projectorcentral.com/mmm/lcd_dlp.htm
 
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