Does this mean my CRT monitor is starting to go?

Discussion in 'Digital Darkroom' started by jimsimmons, Apr 26, 2009.

  1. I calibrate my CRT every 2-3 weeks with Monaco EZcolor. The past few calibrations I've noticed that the brightness settings I'm having to use to get the calibration to spec has used a gradually increasing number. For a few years, the correct brightness setting was round 76-77. Then it crept up to around 82, and recently it's started to need 86-87 for proper calibration.
    Does this mean I may be needing a new monitor before too long? The monitor is a 21" IBM, with Sony Trinitron tube.
     
  2. It's a sign of a weak tube and also electronics. Remember making a CRT monitor can be expensive for the manufacturer and they will conserve costs where ever they can. The high voltage section of a monitor is usually where they skimp the most, and directly impacts brightness / contrast. This is also the most strained section in the entire monitor.
    I would not worry about it until the day it does not calibrate or fails to work. It will probably be a slow decline.
     
  3. digitaldog

    digitaldog Andrew Rodney

    Yup, time for a new door stop when you can't hit the target luminance and the software tells you so.
    All those values are pretty darn low!
     
  4. "All those values are pretty darn low! "
    If the values (76-87) are settings on the monitor itself how do you know they are low? For my CRT I have to reduce brightness to about 23/100 to get a good calibration (to around 80 cd/m2 which is what I prefer for print matching.

    When the CRT is no longer able to hit your luminance targets, or the steps you have to take to get it there result in dramatic changes through your calibration software, then your CRT is done.
    One way to keep the CRT alive longer is to turn it off entirely when you're not using it- don't let it sit in screensaver mode or stay on at all when it's not in active use.
     
  5. digitaldog

    digitaldog Andrew Rodney

    If the values (76-87) are settings on the monitor itself how do you know they are low?​
    Are you not referring to cd/m2? That's what you need to be targeting for calibration.
    80cd/m2 is also darn low. You'll need a pretty low print viewing luminance to provide a match. You'll also need to be in a very, very dark ambient condition although that's always a good thing, even when driving displays at higher luminance.
     
  6. 80-90cdm2 is not where CRT should be? vs 110-120cdm2 for LCD?
     
  7. There's nothing wrong with your CRT except gradual aging, caused by aging of the phosphors and electron guns. As long as you can obtain your target luminance and color temperature you are in good shape. Don't use the observed needed increase in brightness setting to predict how soon your CRT will become unusable; a couple of years ago my then 7 year old Sony/Dell 21" Trinitron CRT had a similar behavior but after I got close to 100% of needed brightness adjustment, it went down again to around 90% and it has stayed around that value ever since.
    80cd/m^2 is a tad low, but you can't get it much higher than 90 anyway. Enjoy your monitor as long as it can be calibrated correctly.
     
  8. digitaldog

    digitaldog Andrew Rodney

    80-90cdm2 is not where CRT should be? vs 110-120cdm2 for LCD?​
    There is no "right" settings. The right settings are those that you can hit and produce a screen to print match (so the viewing conditions of the print come into play).
     
  9. 80-90cdm2 is not where CRT should be? vs 110-120cdm2 for LCD?​
    CRT's or LCD's shouldn't be at any value other than match the brightness of the viewing lighting. CRT's never could put out more than about 90cd/m^2 so you had to match the lighting to that value. LCD's are way brighter than CRT's but need to be throttled down to anything between say 90 and 130cd/m^2 to match the viewing lighting.
     
  10. Honestly I don't think I've ever seen a monitor that used actual units of measure for its settings. I've only scene ones that used percentage scales. A brightness of 76-77 is most likely a percentage and not even neccesarily a linear one.
     
  11. Honestly I don't think I've ever seen a monitor that used actual units of measure for its settings. I've only seen ones that used percentage scales. A brightness of 76-77 is most likely a percentage and not even neccesarily a linear one.
     
  12. Is the brightness of the screen possible to repair or not?
    btw, I am not suggesting you do so.
    I use a couple of 24" CRT's Sony/Sgi, and had a RED color gun problem, and I had it repaied for $150.
    I wonder if over time I have to just accept these giving up the ghost, or it is possble to have this serviced? Or maybe a repair place/service can adjust and replace parts and make it "proper working condition" ? I have a few 30" lcds, but these 2 I am not willing to give up. Anyone with some info on this? If I don't get much info here, I will make a new thread.
    thx
     
  13. CRT monitor brightness is determined by the health of the CRT electron guns and phosphors, user adjustments, calibration and properly functioning control circuitry, including the high-voltage power supply . Whether or not repairs can be made if brightness falls off, depends on what's causing it. Electron gun or phosphor aging can only be undone by replacing the CRT tube; power supply or other malfunctions may be repairable, but it depends on how much those repairs would cost and how much remaining life there is in the rest of the unit. If the unit is over say 5 years old, my guess is that it's not economically feasible to make repairs.
     
  14. A good way to see if your CRT is down for the count can be determined by comparing the 3D gamut plot of your final profile against sRGB. Also if you can get it to show a black to white gradient as smooth as possible without any noticeable banding and color crossover/duotone effect.
    Check out this thread:
    http://www.photo.net/digital-darkroom-forum/00T7EH
    and scroll to the bottom where I show a simplified gamut plot comparison within i1Display's i1Match software against an old Trinitron.
     
  15. Well, this is lots of good feedback. Thanks everyone. From what I'm reading, I probably don't have a problem... for now at least, because I am easily able to get the monitor calibrated. I don't see a change in the 2-3 weeks between calibrating it; I'm just habitual about doing it.
    The numbers I was referring to are indeed, as Steven C suggested, not meaningful numbers, just where on a 1-100 scale the current setting for "brightness" is. So, like I said, that number has moved from ~76 to ~86 in 5 years. Even if the rate of change is increasing more rapidly, I may have some time before EZcolour says it can't get the monitor calibrated.
    Cheers, Jim
     
  16. I think Jim values were not obtained luminance, but position of the slider in monitor OSD. E.g. to achieve target luminance (whatever it was) dialing 77 on the slider was enough initially but now requires to dial 86. This is sign of ageing monitor. Mine has similar problem but more with black levels. I'm still using it but it's clear that before long I need to get new monitor, and Jim apparently too.
     
  17. ...but it's clear that before long I need to get new monitor, and Jim apparently too.​
    Those monitors, like mine, may have still many years of solid service in them.
     
  18. I agree, Frans. I'm not going shopping until I have to!
     
  19. I have a Trinitron myself. Best monitor I've ever used. If you live in a large city keep an eye in the thrift stores. You might want to buy a spare just in case. I saw a big Sony Trinitron in one of those stores just today for $5! Was on my bike and couldn't get it. Everyone (not me) is getting those crappy thin monitors and giving their old CRT's away because they're big and heavy.
     
  20. Everyone (not me) is getting those crappy thin monitors and giving their old CRT's away because they're big and heavy.​
    While I dearly love my 21" Sony Trinitron, my next monitor will be an LCD and it won't be crappy. Ever thought about that maybe the $5 CRT at the thrift store was given up because it had become crappy?
     

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