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Theory on rainbows

Discussion in 'Projectors, Screens & Video Processors' started by Timbo21, Aug 26, 2005.

  1. Timbo21

    Timbo21
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    I do tend to see rainbows & I have always had a bit of a lazy eye, you know
    wanders out of sync with the other. When I get tired it tends to do this, and
    some forum members have said they become more susceptible to rainbows when they're tired.

    So, if the eyes are out of sync then they may pick up what the colour wheel is doing - whatever that is, someone with more knowledge might be able to expand on this.

    This would explain why some people suffered & some didn't. Additionally, this
    might put undue strain on the eyes, with perhaps the strobe effect (not sure if it has a strobe effect, just a theory) of the colour wheel interacting on each eye differently - rather than in sync with a person who's eyes are properly 'locked' together - thus creating a strain on the eye muscles with the brain trying to marry these two slightly different signals.

    There you go. A load of old twoddle :rotfl: , or is there something in it?

    Answers on a post card, or failing that, reply to this thread. ;)
     
  2. squibbly

    squibbly
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    From what I've read, there are people who see rainbows but don't get eyestrain/headaches, people who don't see rainbows but get the eyestrain and people who suffer from both (and let's not forget the fortunate majority, who aren't affected by either).

    I myself can see the odd rainbow on a 2X colour wheel, but can only see them if I look for them on 4X and above. To be honest, I'd have bought a DLP if the only problem was the rainbows (they don't really detract from the viewing experience for me, unlike some people who see them everywhere). It's the mild eyestrain on both speeds that gets to me and forced me to abandon my hopes of DLP!

    I think that the rainbows are caused by the red, green and blue separating on the back of the retina as you move your eyes, since they are not happening at exactly the same time and the movement of the eyes causes them to split - with a faster wheel, this would therefore be less noticeable.

    I think that the eyestrain is caused by the constant changing of colours causing strain on the colour receptors of those of us with more sensitive eyes. After all, this is not an affect replicated in nature (I'm now expecting a chorus of, 'but have you never seen a rainbow in the sky, squibbly?', but you get my drift), so we haven't exactly had to evolve to cope with it!

    Just my thoughts as a layman! Now can we have increasingly fantastical and spurious contributions, please!
     
  3. Mark_a

    Mark_a
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    You can generate rainbows anytime you want with a DLP system by crunching on something like a fresh apple while you're watching the TV. Items with strong contrast on the screen tend to produce the most obvious effects. This would seem to indicate that jiggling the fluid in the eye has something to do with it. So if you're a heavy breather, cough or sniff a lot, then I'd expect you to see rainbows quite often. Perhaps if you live near a road with heavy traffic would also cause low-level vibration you're not normally aware off that is vibrating the optic fluid? Maybe you've even got your kick-ass sound system turned up too high and that's also vibrating the air?

    Fantastical enough for you? :)

    Regards

    Mark
     
  4. Timbo21

    Timbo21
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    I got eye strain on a 5700 & saw rainbows, but on 7205 I see a few rainbows,
    especially on text credits, but no strain on 7205.

    Why does tiredness make it worse? If there is anything in the 'lazy eye' theory,
    then this would explain why it got worse when tired, since the eye wanders
    from the other more when tired.

    More fantastical theories please! :smashin:
     
  5. Nick_UK

    Nick_UK
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    There's nothing fantastical about it. The "persistance of vision" effect is more pronounced in some people than it is in others, that's all.
     
  6. Timbo21

    Timbo21
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    Vibrating optic fluid...mmm, I like it. :)

    But doctor what ees making zis fluid, az you zay 'vibrate' ween they ees not eeting zee apple or leesening to zee 'keek-ass sound system' making zee molecules vibrating in zee air transmitting to zee optical fluid. :eek:
     
  7. Timbo21

    Timbo21
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    Okay, but why?
     
  8. Nick_UK

    Nick_UK
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    Because the eye is not electronic, it's biological, and everyone is different. Even certain foods can affect the operation of the eye, and drugs certainly do.

    Food additives can affect sight
     
  9. spamboy

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    My wife had eye problems (and operations) as a child to cure a lazy eye. She still only looks out of one eye at a time (has no depth perception). Any dlp we've demo'd drives her crazy.
     
  10. NicolasB

    NicolasB
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    DLP rainbows are caused by the red, green and blue parts of the image landing on slightly different places on the retina - anything that causes the eye to move between sub-frames will make them worse. A "lazy eye" would certainly have this effect.
     
  11. Timbo21

    Timbo21
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    That's the last chinese I'm eating!

    I once saw my mate turn into a gorilla after taking drugs. :eek:
    So, I would definitely say drugs affect your vision.

    It was a rather nasty adverse reaction to some aspirin. :) Luckily I am a responsible & grown up person now with children & do not recommend to anyone any aspirin in case it has this similar detrimental affect on their vision.

    Thank you :)
     
  12. squibbly

    squibbly
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    Come on, we can get more outrageous than this!

    I believe that the wearing of a blue check gingham dress and ruby slippers whilst waching DLP projectors causes you to see rainbows without fail. This is known as 'The Judy Garland Effect'.

    There is a related syndrome which involves a small black dog yapping next to you in a basket and causing you a headache. I will leave you to guess what that is called.

    :thumbsup:

    My mother used to tell me that playing too much with your remote control gives you eyestrain and can even send you blind.

    Squibbly :)
     
  13. Timbo21

    Timbo21
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    :eek: I hope I don't get to suffer the JGE.
     
  14. squibbly

    squibbly
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    Unfortunately I have!

    Squibbly :mad:
     

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  15. Timbo21

    Timbo21
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    :rotfl: :rotfl: B***dy Hell Squibbly! You're a brave man to post that.

    dee dee dee dee, dee dee dee dee...You have just entered the Twilight Zone.
    :eek: :eek:

    Where in God's name did you get that? Actually, please don't tell me. :rotfl:

    I hope I don't get nightmares now. :)
     
  16. Gary Lightfoot

    Gary Lightfoot
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    Scary. :eek:

    Thank God I don't suffer from rainbows....

    :)
     
  17. gingerone

    gingerone
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    Fair do's Squibly, you're not right at all.
     
  18. Timbo21

    Timbo21
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    Squibbly must be commended on....well, being very squibbly. I would like to say he is a top bloke for amusing me so much. :smashin:

    Squibbly, if you're out there can you expand on the cause of 'The Judy Garland Effect' & how long you have been aflicted with this most serious of conditions?
     
  19. Gary Lightfoot

    Gary Lightfoot
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    I think Rimmer from Red Dwarf had similar tendencies at one time IIRC. :)

    Gary.
     
  20. Timbo21

    Timbo21
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    Did squibbly get the gear on specialy for the thread, or is it an archive photo?
     
  21. squibbly

    squibbly
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    Sadly it is an archive photo (of me, I admit). Maybe I should put it in my signature here? I never expected an avforums thread to get to such a point where it was compulsory that I posted it! I should point out that it was a fancy dress at work, and not a lifestyle choice. Though that's not to say that this forum wouldn't benefit from the odd transvestite. Let's face it, we don't even have any women who post here!

    The most amusing effect was when I was in the works loos having a pee with my skirt hitched up and the chief exec came in, took one look at me and went straight into a cubicle! Fair dos to him though, he did award me first prize. I was managing a dozen staff at the time and it didn't seem to undermine my management of them!

    That picture does disturb my children and my sister more than anyone though. It tickles the wife.

    Squibbly
     
  22. Timbo21

    Timbo21
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    Poor kids :( They have my sympathy :) . Sisters need to be disturbed :thumbsup:

    Squibbly, if you can do that to all the threads you will be making the avforums
    a much more entertaining place :thumbsup:

    I fear tho that it would be too expensive for the fancy dress bill :(

    All the best,

    Tim.
     

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