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Discussion Starter · #1 ·
Hello,


I get a Barco cine7. I see rainbow effect in the white (blue and green). I'm surprise to see this on crt. On a dlp I'm allright there is but on crt, I don't understand. Convergence is ok.


I have rvbs connection on my old pioneer 717. I'm on 15Khz and 50 hz. Do you think this effect dissapear if I connect a pc to switch on 100 hz vertical refresh ?

Or there is a problem in the crt. I'm the only to see this effect. I would like to stop it.


Thanks


Faulken
 

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I would have guessed a convergence issue, but if you say that your convergence is right, then I am curious about what the wiser heads offer.


Later,

Bill
 

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Discussion Starter · #3 ·
On my crt, I"m sure that is the blue that make this effect. If I select Red and green only. I see no effect. When I select blue and green the effect restart. If I god down the color temperature the effect go down.


I think the three tube are not synchronize between us.



Faulken
 

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I remember an old thread about this problem.

The bad thing is: yes, it's true. Even the crt have the rainbow effect !!

It's a effect of the different latency between the phospor of the crt. The decay of the "on" spot is, a bit, but different.

There are not many people that see this problem. I'm afraid that your're one of them.


Hi,

Vincenzo
 

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Discussion Starter · #5 ·
When I use internal mire of the crt. I see the rainbow on 15K 50hz. I don't see this on 69K 100 hz.

A dealer notice me that if I work on 100 hz vertical refresh, the effect disseaper.

I will made a vga 4bnc cable to connect my computer.

I see that the limo and lido Barco card work with 100 or 120 hz refresh. I think this is not a hazard.


On a showroom, I see cine7 and I never see rainbow. But I don't remember if there is lido or limo in it.


I try to ameliorate my convergence.


I'm suprise player dvd who use Faroudja processor can't work in 100hz. But the processor can do this. I don't want to buy Philips 963. There are so bug in this player.

I'm waiting the first wma9 player to change my 717.


Faulken
 

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Are you sure you are seeing an actual color separation dubbed rainbow that some people describe when they see color separation in DLP projectors?


Previously, I have noted in this chatroom that I was seeing something similar to the rainbow effect, but on my CRT-based RPTV. At the time (and to this moment) I am not exactly sure what it is. The saccidic response, as Guy Kuo related to, is the brain's blanking system that is turned off because the blurring that triggers the saccidic response isn't there as the color separations are not blurry, but sharp.


So, I guess I can see where a persistence of phosphor combined with a very-converged and sharp setup could produce similar results. My advice is to start stoking or slam-dunking and try to ignore the condition if accurately identified. :)
 

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It sounds like is is more a moire effect than a rainbow. Interesting
 

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Running video through RGB at only 15khz is creating this effect I think. Try to use a composite or s-video connection and see if you still see it.


Per Johnny
 

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Yes the CRT rainbow is a issue of the different shining time of the three phosphors. Green for example shines very long time after the electron beam hit the phosphor.

I started such a thread in the german homecinema board a time ago. I see this effect all the time. It is very annoying. Surely the DLP rainbow is much stronger, but this effect is also noticable by some people. It can be forced if you turn your eyes fast from side to side. It can be seen easily with bright objects on dark background.
 

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"I started such a thread in the german homecinema board a time ago. I see this effect all the time."


I will think it is not the phosphor that creates what you call a rainbow effect, but the lenses. Some lenses arent good enough and separate the spectrum of the light. It can also be the liquid that has gone bad. I am sure that you wont see this on crt projectors with everything woriking properly.


Per Johnny
 

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@Per Johnny

No, it is definitely a time based phenomenon. I see it on my liquid coupled Sony 1292 with HD-10F lenses (exist better ones? ;)). I also saw it on a Barco 1208/2.

It is there when I move the eyes otherwise not. So it has to be a time based effect.

What you mean is the chromatic seperation of "bad" lenses. But this has to be always visible also if you hold still your eyes.
 

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Nils, if this is a problem for you, you are certainly doomed. I cant force this effect even if I try, and I have tried every crt projector out there. Some people always see things that the marjority dosent see. Seems that there will be few projector-technologies out there that can satisfy you.


Do you mean that you see this with every crt-projector you have seen?


Per Johnny
 

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@Per Johnny

I saw this on every CRT, yes. And also on higher refresh rates.


I think that the "time sensivity" of human eyes are very different. I know people who don't see the DLP rainbow and even don't see the 48 Hz flicker. I for myself sadly see those effects. There is nothing I can do against this.
 

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Nils, I am not an eye-doctor, but do you see it if you are blocking one of the eyes also?


I see rainbows even on high-speed DLP-projectors, but I am not bothered with 50hz or even 48hz on crt-projectors, still I prefer higher refresh-rates. I can use DLP-projectors without getting eyestrain, but I couldnt live with it.


Per Johnny
 

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Discussion Starter · #16 ·
I see this effect when I block one of the eyes, the left and the right only. I got no problems with my eyes.

I tried progressive scan player, and the effect is allready here.


An other think, It's possible that this is the room. My room is clear. I know a friend who got an 801s with a dark room. I never see this effect. I work in 15 K.


Faulken
 
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