CRT vs LCD vs eyesight?

Discussion in 'Displays' started by Nye553, Aug 31, 2004.

  1. Nye553

    Nye553 Gawd

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    Is it a fact that CRT monitors destroy your eyesight vs LCD which don't?? Or just that LCD monitors are better for people who have bad eyesight??
     
  2. agentzero9

    agentzero9 2[H]4U

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    LCDs are easier on the eyes, resulting in less eye strain. YMMV

    As for the long-term effects of CRTs, it may be too early to tell. Only in the last decade have we seen the birth of a generation (both young and old) that spend a thousand hours a year 14 inches away from a CRT screen. It may not be until the year 2020 until we see the damage inflicted by extended viewing of CRTs.

    And on the other hand, we may find out there is nothing to worry about at all.
     
  3. Nye553

    Nye553 Gawd

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    Okay, thanks for the reply
     
  4. Kevin Lowe

    Kevin Lowe Gawd

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    I used to have horrible headaches - the kind that make you sick. I switched from a 17" Sony Trinitron to a Samsung 710T, and haven't had a headache like that since, despite running at an even higher resolution than before.

    Then again, I wear glasses without an anti-reflective coating (UV-sensitive lenses), so if you have normal eyesight, YMMV.
     
  5. JackieO

    JackieO Gawd

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    I have to agree witht he above poster. While this sort of evidence is all anecdotal, since I switched to Plasma/LCD/FP displays only I've had much less eye strain. I used to sit in front of a 19 inch 60Hz CRT at work for 14 hours pretty regularly and had pretty bad headaches. I suppose a million other things may have helped also, but I certainly notice less eye strain when working on LCDs.
     
  6. Nye553

    Nye553 Gawd

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    Okay... so so far having a CRT can only cause eye strain and not eye damage that we know of to this day... and having LCDs might/can cause less strain. That's what i'm concluding from the following posts.
     
  7. emorphien

    emorphien 2[H]4U

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    I had a 19" CRT that I ran at all kinds of refresh rates but I still got migraines from it and other CRTs. I had prescription medication that would help but that was not really a good way to solve the problem. I eventually got an LCD and my migraines went away... I still use the CRT all the time but because it's not my main screens and my eyes don't focus on it I'm doing much better.

    The CRT does increase eyestrain and in some cases may damage eyesight eventually (jurys still out). But it doesn't necessarily affect everyone probably. If you have a problem though you aren't in an uncommon situation and an LCD should help.
     
  8. JackieO

    JackieO Gawd

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    Ya, like I said it's all anecdotal evidence, but there is a lot of it. Plus it's just plain common sense. I would say that if a person is worried about eye strain or has problems with focusing on CRTs for extended periods of time then investing in a nice LCD is a good choice.
     
  9. Nye553

    Nye553 Gawd

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    I wish I had money for a nice LCD screen.... :( :mad: :rolleyes: .......... me need money ;)
     
  10. Elledan

    Elledan [H]ard|DCer of the Month - April 2010

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    CRTs don't damage your vision, eye strain does.

    I'm willing to bet that over 90% of the CRTs currently being used are configured improperly. Low refreshrates, poorly calibrated vertical and horizontal sync circuits, brightness and contrast levels set way too high or too low, etc.

    Fact is that CRTs are more difficult to configure than LCD displays. The electron guns must fire at exactly the right moment at exactly the right spot in order to get the best image possible. This requires a good design of the CRT and someone to adjust the circuits until they work optimally. In other words, blame that cheap CRT you bought and the manufacturer of it, but not CRTs in general.

    If you were to spend as much on a CRT as you would on a low-end TFT and then pay an expert to calibrate it for you, then you'll be amazed at the image quality.

    Of course, some people are very susceptible to the flickering caused by a rapidly refreshing display, but those people can't even watch TV if it's a CRT one without getting an instant headache.
     
  11. Nye553

    Nye553 Gawd

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    Would it be so hard for me to calibrate it myself?...I got the cheapest 17" CRT monitor from dell with my dell dimension 8400(it was free though so I'll take it)... I don't have money right now to buy the monitor I want.
    I'm so glad i'm not one of those people
     
  12. _jd_

    _jd_ [H]Lite

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    well this might go against the conventional wisdom but here:

    i've just returned a samsung 712N i had for 2 weeks (it was just a test drive) and during those 2 weeks i have constantly felt like i had a headache starting- not quite a full blown headache yet, but enough to feel uncomfortable. i do spend a lot of time in front of my comp so i wanted to get a nice lcd to do my eyes a favour, but right now i'm not so sure about it all anymore.

    couple more details:
    - i think i need glasses, haven't gotten around to get an exam yet
    - even with large fonts in Win i found all the text just too small, so that would probably account for the problem
    (special greetings to all those wonderful webdesigners who think fixed-size fonts and flash crapsites with tiny little text are cool :rolleyes: )
    - i do seem to have some issues with fluorescent and neon lights so i dunno if that could be a problem for me with the lcd backlights and all... anyone else out there feeling weird when using lcd ?

    i have no problem staring at a decent crt for long periods of time (uhm..like 24 hours :cool: (and no i'm not addicted to pc games :p )) as long as it's @ 85/100 Hz and not too bright (i seem to have my monitors (and tvs for that matter) set a little 'darker' than most people). At the same time i'm VERY sensitive to flicker at lower refresh rates (i will never understand how anyone can look at a monitor @60Hz)

    anyways, if anyone can make some sense of it...
     
  13. tiebird321

    tiebird321 [H]ard|Gawd

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    been using crt's for the last 15years
    not one problem ever
    eyes still at 20/20
    never a single headache

    still have yet to see an lcd with good full spectrum color.
     
  14. Elledan

    Elledan [H]ard|DCer of the Month - April 2010

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    Calibrating a CRT involves opening it, then while supplying the monitor with a test signal, you change the configuration of the potentiometers of the vertical- and horizontal sync circuits (and possibly some others), while monitoring the output signal(s) by watching the image on the screen or by having it hooked up to an oscilloscope, or both.

    However, this is definitely _not_ a task for an inexperienced person. The voltages employed in the high-voltage circuitry (including the electron guns on top of the 'neck' of the tube) are rated in the tens of thousands of volts and could easily kill or injure you. On top of that, while a CRT is opened and operating, x-rays are generated by certain components, exposing anyone within view of the exposed innards of the CRT to this type of radiation. And while it's not enough radiation to cause cancer or render one sterile, it's a bad idea to expose oneself to it for extended periods of time.

    If you don't know what any of the above means and have had no training in repairing CRTs or similar, don't even think about calibrating it yourself. It's just not worth the risk.

    You can however partially calibrate a CRT by using the OSD options, accessible by the button(s) at the front, although the effect of this is limited except in the most severe cases.
     
  15. Elledan

    Elledan [H]ard|DCer of the Month - April 2010

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    The main problem I have with LCDs is that whenever I'm forced to use one, it's set to such a high brightness level that I'm afraid it'll burn out my retina :eek:

    Slightly flickering fluorescent lights do make me feel kind of uncomfortable too.

    I used to be able to tolerate 60 Hz quite well, back when I was using a 14" CRT with a 1024x786 resolution, now I immediately get this nauseous feeling right down to the bottom of my stomach the moment I look at a monitor with such refreshrate settings. The same counts for cheap TVs (poor alignment of the lines) and TVs receiving a poor or bad signal.
     
  16. emorphien

    emorphien 2[H]4U

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    Elledan, there's still one fundamental difference in how CRTs and LCDs function, and that's that CRTs don't have the image permanence. It's constantly refreshing and for some that may be the source of eyestrain. I've worked on tuned & calibrated barco reference monitors and felt uncomfortable. And we're talking a $5000 19/21" (i forget now, it was a year ago) screen.

    TVs can do the same to me, but not quite as fast because I'm not sitting as close to them. If I do get close to a TV however a migraine will come quickly.
     
  17. nevamore

    nevamore Limp Gawd

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    As someone who wears glasses due to astigmatism, I can tell you this condition is sometimes brought on by glare.

    In my case I look at computer screens 8-10 hours a day. I have a dual-display setup on my desk at work. I began getting migraine-type headaches every day. The eye doctor diagnosed astigmatism and prescribed glasses with anti-glare coating on/in them.

    One way you can recognize the same problem I have is if you feel you have difficulty focusing on objects or car lights at night bother you.

    In my case it was the glare off the glass of the CRTs that was hurting my eyes. The headaches were a result of the muscles in the eyes over working themselves to focus through the glare.

    I have since switched to LCDs at work and home and rarely experience any headaches.
     
  18. ciggy50

    ciggy50 [H]ard|Gawd

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    i wont take that bet :p \

    too often i too have seen crt's that are not setup properly ,
    matter of fact i have been given a few "dead"crt's that simply had the contrast and brightness turn off :D


    gawd i love NOOB's :p
     
  19. JackieO

    JackieO Gawd

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    Ya, the funny thing is everyone in this thread is right. CRTs likely do not cause eye damage but the eye strain assosiated with improperly setup ones does. LCDs aren't infallible either - I know a few people who have sensetivity to neon and flourescent lights that have a tough time using them even at really low brightness levels. Someone else brought up glare, which is a *huge* problem for people who use computer monitors all day. For me, LCD's seem to help with my headaches/vertigo/eye strain quite a bit. There's a guy here at my office that uses a front projection system because he can't standlooking at anything where the light either direct view or rear projected. It's weird.


    As for calibration, if you own an expensive TV or monitor and spend a lot of time watching it I've always been a fan of ISF calibration (google it). It costs $3-$400, but most people who have it done swear by it. Obviously there are less expensive solutions like AVIA or DVE DVDs.
     
  20. Nye553

    Nye553 Gawd

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    well in that case I'll give it a go!! :p and if I die ciggy50 can have my 17" CRT ;)
     
  21. ZXN

    ZXN Gawd

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    Less eye strain with a trinitron monitor...But I have 20/20 vision and Im 21...been using crt's since I was 12
     
  22. Nye553

    Nye553 Gawd

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    I'd buy money for trinitron monitor if I wasn't going to college and had extra money... but right now I hopefully won't spending too much time playing CS.
     
  23. eastvillager

    eastvillager [H]ard|Gawd

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    I switched to LCD at work and home and no longer get eye strain.


    Even with properly configured CRTs at home and work, I'd still have issues because I'd be switching between monitors with different refresh rates.

    Now, working with LCD, the only real calibration I do for work machines is make sure it is on DVI and running at native resolution.
     
  24. agentzero9

    agentzero9 2[H]4U

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    You are lucky to not have eyestrain from extened CRT viewing.


    I think the people who DO get eyestrain, are the ones who should worry about permenant damage from CRTs. I of course am one of those people.
     
  25. SFI

    SFI Gawd

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    what about those radioation/uv blocking things, that u place over your monitor and it screens you from such harmful things. do those help?

    i have a viewsonic g220 (in black) at 1600x1200 @ 85hz, i don't really get eyestrain but reducing glare might be nice (which those solutions do)
     
  26. Elledan

    Elledan [H]ard|DCer of the Month - April 2010

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    Those are absolutely nonsense if you're using a somewhat new display (1990 or newer). There are regulations in place which specifically limit the allowable radiation to be produced by a CRT to safe levels. In fact, exposing your body to sunlight is far more dangerous than sitting in front of a CRT.

    The best way to prevent glare is to not aim the screen at any lightsources (including windows). However, any further reduction in glare is good.
     
  27. Miipp

    Miipp n00bie

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    This analogy is not suitable, the UV A/B from the sun are very strong radiation to skin and eye
     
  28. Big Fred

    Big Fred n00bie

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    I know my eyeisght has gotten worse and it directly crrelates with the ammount of time spent on the computer. However, I know it is from constantly focusing on something very close to the eyes for an extended period. I have always used CRT's no headaches. Just eyesite declination since Super Mario Bros., Sat out all games until Dreamcast. During that time my eyesite was steady. Then back to the computer and my prescriptions kept getting stronger again. I heard a little too late to look at least 20 ft. away every 20 min. for 20 sec. to help reduce this effect.
     
  29. Elledan

    Elledan [H]ard|DCer of the Month - April 2010

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    That's what I said, didn't I?
     
  30. needmorecarnitine

    needmorecarnitine [H]ardness Supreme

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    Exposing your body to sunlight is totally natural and required for optimal health

    Don't believe everything you see/read on tv/magazines
     
  31. needmorecarnitine

    needmorecarnitine [H]ardness Supreme

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    they are very weak forms of radiation

    try some quantitative terms
     
  32. Elledan

    Elledan [H]ard|DCer of the Month - April 2010

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    A brief (two hours max) exposure to UV-B each day is required to produce certain important compounds, like vitamin D, except when those compounds are taken in through food or other means. Any longer than that is unnecessary and unhealthy.
     
  33. needmorecarnitine

    needmorecarnitine [H]ardness Supreme

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    How much vitamin D do you need to make?

    Are you accounting for different melanin levels? How about lattitude and time of the year?
     
  34. goodboy997

    goodboy997 n00bie

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    I bought a CRT 6 months ago but it is now under repair. I know that it is product that is fading ouy. But I don't expect that the quality is also fading out for such low end product. I am searching for a cheap LCD now.
     
  35. Techno Pride

    Techno Pride Limp Gawd

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    I get headaches from prolonged use on my 17" CRT (creative branded) running 1024x768@85hz

    but my eyesight's 6/6 and I'm 21yrs old. I like to use the computer in the dark as well :p
     
  36. TheFury

    TheFury n00bie

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    a cheap and easy solution to a lot of the eyestrain issues from focusing too close is to buy some reading glasses. just wear them whenever you're using the computer/playing games when the monitor is close to you. the reading glasses do the focusing for you so its just as if you're looking at something far away, it doesn't strain your eyes since they barely have to focus themselves. too bad I also figured this out too late and my eyesight is pretty bad, high prescription.
     
  37. Elledan

    Elledan [H]ard|DCer of the Month - April 2010

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    http://www.nlm.nih.gov/medlineplus/ency/article/002405.htm

    The 'two hours of sun'-limit is generally considered the point after which damage to the skin's DNA begins to exceed the repair capabilities of the affected cells.
     
  38. needmorecarnitine

    needmorecarnitine [H]ardness Supreme

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    it may be "generally considered", but, generally people are stupid

    Why do you think I brought up those previous points?
     
  39. Elledan

    Elledan [H]ard|DCer of the Month - April 2010

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    Generally considered by scientists, based on the results of experiments and research.
     
  40. needmorecarnitine

    needmorecarnitine [H]ardness Supreme

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    Where did you learn this?

    Any comments on those variables I brought up (melanin, latitude, seasons)?