Do CRT's like 60 Hz?

WWDWD

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I have been fortunate to acquire a 2060u Mitsubishi CRT and after using it for some time I noticed some interesting results and wonder if anyone else notices this as well.

With Windows 10 and GTX 980 ti with a DVI to VGA adapter, when running at 2048 x 1536 at 75 Hz text appears to be soft. Reducing the brightness doesn't seem to improve the sharpness and I even tried to adjust the focus which I found is already peaked. However if I drop the frame rate from 75 to 60 Hz everything is noticeably sharper at 2048 x 1536, what is going on here?
 
This is just pulling out of my ass, but I wonder if the digital to analog is just not fast enough to get clean transitions with high contrast like you have with text. I wonder if you compare 2048 x 1536 @60 with 1920 x 1440 @ 75; which have a similar number of pixels per second.
 
This is just pulling out of my ass, but I wonder if the digital to analog is just not fast enough to get clean transitions with high contrast like you have with text. I wonder if you compare 2048 x 1536 @60 with 1920 x 1440 @ 75; which have a similar number of pixels per second.
You’re almost there. 2048x1536 is beyond that monitors ability to resolve. 0.24mm stripe pitch is only good to about 1700 horizontal pixels for full resolution. And that’s not even taking video chain bandwidth into consideration.
Your recommendation is appropriate though. I wouldn’t personally jack the resolution up that high unless playing games.
 
This is just pulling out of my ass, but I wonder if the digital to analog is just not fast enough to get clean transitions with high contrast like you have with text. I wonder if you compare 2048 x 1536 @60 with 1920 x 1440 @ 75; which have a similar number of pixels per second.
I gave it a try, 1920 x 1440 at 75, the text was slightly more fuzzy but again at 60 Hz the text is sharper. I even tried 1600 x 1200 however the improvement with text sharpness was more gradual and at 1280 x 1024 I noticed no difference, weird.
 
At 1280x1024 you should be in scanline territory, so you probably won’t see any real differences.
 
You’re almost there. 2048x1536 is beyond that monitors ability to resolve. 0.24mm stripe pitch is only good to about 1700 horizontal pixels for full resolution. And that’s not even taking video chain bandwidth into consideration.
Your recommendation is appropriate though. I wouldn’t personally jack the resolution up that high unless playing games.
Good point, exceeding the resolution at which can't be resolved by the tube because of dot pitch. I think I got my answer, thanks
 
I gave it a try, 1920 x 1440 at 75, the text was slightly more fuzzy but again at 60 Hz the text is sharper. I even tried 1600 x 1200 however the improvement with text sharpness was more gradual and at 1280 x 1024 I noticed no difference, weird.
The guns in that monitor may just have issues with operating at higher refresh rates and may not be able to get their tracking quite as accurate. Back in the day you saw variance tube to tube like that. You could have one monitor that was razor sharp, another that had issues being fuzzy. The higher the rez and the faster the refresh, the quicker those electron beams have to be steered and that is harder. Also there can be shielding issues and RFI can leak in and disturb things.

My last CRT was quite bad for that and had real issues at high rez, it never looked clean and sharp at 1600x1200, no matter what, and it was a high end Lacie Electron22Blue.
 
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The guns in that monitor may just have issues with operating at higher refresh rates and may not be able to get their tracking quite as accurate. Back in the day you saw variance tube to tube like that. You could have one monitor that was razor sharp, another that had issues being fuzzy. The higher the rez and the faster the refresh, the quicker those electron beams have to be steered and that is harder. Also there can be shielding issues and RFI can leak in and disturb things.

My last CRT was quite bad for that and had real issues at high rez, it never looked clean and sharp at 1600x1200, no matter what, and it was a high end Lacie Electron22Blue.
Interesting details, thanks for sharing
 
Cheper CRTs have more distortion when driven at higher speeds. Your bandwidth used is a combination of resolution * refresh rate.

Also, if you drive it beyond the native DPI, you're just adding distortion for no noticeable resolution increase. For anything less than professional CRT (think Sony, every Diamondtron has trash electronics), you should limit yourself to the following:

17": 1024x768 @85hz.
19": 1280x960 @85hz.
22": 1600x1200 @85hz.

You have one of the highest-quality VGA outputs you can buy with that Maxwell card, so any blur is just the limitations of your CRT internal electronics.
 
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Cheper CRTs have more distortion when driven at higher speeds. Your bandwidth used is a combination of resolution * refresh rate.

Also, if you drive it beyond the native DPI, you're just adding distortion for no noticeable resolution increase. For anything less than professional CRT (think Sony, every Diamondtron has trash electronics), you should limit yourself to the following:

17": 1024x768 @85hz.
19": 1280x960 @85hz.
22": 1600x1200 @85hz.

You have one of the highest-quality VGA outputs you can buy with that Maxwell card, so any blur is just the limitations of your CRT internal electronics.
When you mention "Professional CRT" I take it that you mean something like a BVM PVM (Broadcast Video Monitor) (Professional Video Monitor) which I hear is built like a tank and costs a crazy amount of money if you tried to buy a new one in the day.
 
Holy shit, I had this WAY back in the day! If I remember correctly I had to have a very short DVI-D cable and run it a few resolutions lower for crisp text. Refresh rate didn't matter. I found that the monitor also looked better when it wasn't on a shared power source as my computer at the time but I'm not sure how much that solution really helps anything all these years later.
 
Holy shit, I had this WAY back in the day! If I remember correctly I had to have a very short DVI-D cable and run it a few resolutions lower for crisp text. Refresh rate didn't matter. I found that the monitor also looked better when it wasn't on a shared power source as my computer at the time but I'm not sure how much that solution really helps anything all these years later.
I think your on to something about checking the power source of the monitor, thanks

I find when I drop the refresh rate to 50 the image is incredibly sharp, sharper than 60 at 2048 x 1536 although it murders your eyes
 
When you mention "Professional CRT" I take it that you mean something like a BVM PVM (Broadcast Video Monitor) (Professional Video Monitor) which I hear is built like a tank and costs a crazy amount of money if you tried to buy a new one in the day.


I mean anything high-end made by Sony. Every other device out there is just a cheap knockoff Aperture Grille.

Look here for high-end CRT discysussions

https://hardforum.com/threads/24-widescreen-crt-fw900-from-ebay-arrived-comments.952788/

Those reference monitors you mentioned in your post tend to be way too small and built for broadcast resolutions - I'm referring to professional content creation monitors from Sony
 
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Yes it's normal for CRT monitors to be less sharp with higher refresh rate, I always noticed slight difference but most of the time it wasn't a day and night difference, pretty marginal. Obviously I would still used 1280x960@100Hz on my 19" trinitron monitors over 85Hz as smoother motion was more beneficial than the minor sacrifice in sharpness not to mention I think flicker disappears completely at 100Hz vs 85Hz it's like you can "feel" it if you focus on it. Likewise noticed the same comparing 1600x1200 @ 100Hz on 21" trinitron/diamondtron monitors vs 85Hz but again, was worth it.
 
How sharper image at lower refresh rate is depends on monitor electronics.
On FW900 I do not notice much difference, even on Delock DP->VGA adapter and certainly less than on CRT's in the past.

Still I suggest to use at least ~100Hz at lowest resolution that allows that.
For 2060u it should be 1600x1200@96Hz or even 97Hz with some vblank lines removed (if that doesn't cause distortions). It pretty much has the same limits as FW900 for horizontal and vertical refresh rates.
 
How sharper image at lower refresh rate is depends on monitor electronics.
On FW900 I do not notice much difference, even on Delock DP->VGA adapter and certainly less than on CRT's in the past.

Still I suggest to use at least ~100Hz at lowest resolution that allows that.
For 2060u it should be 1600x1200@96Hz or even 97Hz with some vblank lines removed (if that doesn't cause distortions). It pretty much has the same limits as FW900 for horizontal and vertical refresh rates.

Thia is What I already told him. you wold think it would get through his thick head by the fifth repetition, right?
 
Interesting to see a discussion about CRTs today. I put up with the slight blur on my stuff because 60Hz flicker would drive me mad. It was as if looking at it made my brain vibrate. Ugh.
 
Thia is What I already told him. you wold think it would get through his thick head by the fifth repetition, right?
I recommended higher refresh rate than 85Hz thus my advice was 11 to 12Hz better 😎
Though on this Mitsubishi the better resolution to use would be 1280x960@117Hz. It would also be within this monitor bandwidth specs of apparently only 240MHz (https://www.cnet.com/products/mitsubishi-diamond-pro-2060u-crt-monitor-22-t4029lla/)

Interesting to see a discussion about CRTs today. I put up with the slight blur on my stuff because 60Hz flicker would drive me mad. It was as if looking at it made my brain vibrate. Ugh.
I have 6 CRT screens:
- 1x SONY GDM-FW900 24" VGA
- 2x SONY PVM 14M2E 14" 15KHz - best colors, support PAL, NTSC, SECAM on Composite and S-Video and RGB and Component
- 1x SONY PVM91CE 9" B&W 15KHz - least flicker due to rather slow phosphors, only support Component Y/Luma 🤗
- 1x Panasonic 21" TV PAL with composite and RGB - do not use this one, though it has quite nice colors
- Tektronix T922R mainly used as a vector display - this one uses Xonar STX as its graphics card 🙃
usmiech.png

Of course this list is subject to change any time as my CRT love is forever and undying.

60Hz really bothers me on FW900 but not so much on any 15KHz screen, especially in progressive (240p) mode.
And 50Hz on FW900 is so irritating it literally makes my eyes hurt in seconds.
These monitors weren't really intended for such low refresh rates. And in some sense it's good because that makes them better for Glorious PC master CRT race gaming 👌
 
Cheper CRTs have more distortion when driven at higher speeds. Your bandwidth used is a combination of resolution * refresh rate.

Also, if you drive it beyond the native DPI, you're just adding distortion for no noticeable resolution increase. For anything less than professional CRT (think Sony, every Diamondtron has trash electronics), you should limit yourself to the following:

17": 1024x768 @85hz.
19": 1280x960 @85hz.
22": 1600x1200 @85hz.

You have one of the highest-quality VGA outputs you can buy with that Maxwell card, so any blur is just the limitations of your CRT internal electronics.

Way back in 2000, the last (only) time I bought a CRT, my two functional requirements were 17" and 1600x1200x60hz; with as cheap as possible as a third non-functional one. I ordered the cheapest no-name display with my size/resolution requirements listed on PriceWatch and rocked its eyechart sized text for the remainder of my college career and a few years afterwards - when the cheapness of what I bought started showing with it failing to complete resetting the beam position to the top of the screen during the sync period. Initially just when powered on then for increasing periods of time afterwards giving me a lovely "rolled down edge" effect first thing in the morning and when I got home after work each day.

The CRTs I had for a few years at work were 19 or 20" 1600x1200x60, better only in having flat not spherical glass. I kept both until they failed because the bean counters were only buying 1280x1024 and then later 1680x1050 LCDs for non management employees.

Other than when in games that couldn't support higher resolutions or that had FPS struggles I don't think I ever ran them at lower/faster resolutions. More content on screen at once has always been my primary criteria for judging how good a display was.
 
I have been fortunate to acquire a 2060u Mitsubishi CRT and after using it for some time I noticed some interesting results and wonder if anyone else notices this as well.

With Windows 10 and GTX 980 ti with a DVI to VGA adapter, when running at 2048 x 1536 at 75 Hz text appears to be soft. Reducing the brightness doesn't seem to improve the sharpness and I even tried to adjust the focus which I found is already peaked. However if I drop the frame rate from 75 to 60 Hz everything is noticeably sharper at 2048 x 1536, what is going on here?
I've read some guy who fixed them said it mostly comes down to the amplifier besides grill pitch. According to him the best CRTs capable of 1600x1200x100 with good sharpness are the ones with Hitachi FA4301 amp: FW900, F500 and F520 being the best. He also said you need a BNC cable for maximum sharpness at higher refresh rates. But even on my F520 the sharpness is still better at lower refresh rates (I don't have a BNC cable though).
 
I recommended higher refresh rate than 85Hz thus my advice was 11 to 12Hz better 😎
Though on this Mitsubishi the better resolution to use would be 1280x960@117Hz. It would also be within this monitor bandwidth specs of apparently only 240MHz (https://www.cnet.com/products/mitsubishi-diamond-pro-2060u-crt-monitor-22-t4029lla/)

YYeah, only Sony could justify the high-end components necessary to max-out a CRT's bandwidth without turning it into a blur. Even Mitsubishi went mass-market with their Diamondtrons. Iiyama was slightly higher-quality (but nowhere near Sony).

You need a market for folks willing to pay around $1000 a display to get what Sony is offering. (had to find when only photo professionals / video editors need that kind pf quality)
 
Good information here.

Does anyone else have to crank up the gamma so the picture is not so dark? I use 1.6 with NVIDIA to make things look better.

Edit
When gamma is set to 1.0 in Nvidia control panel details are lost in the darks as they are way to dark although there is no issues with the white, the tube can get plenty bright. I find if I increase to 1.6 it is comparable to that of the LCD I have which is more revealing of dark details. Although I wonder if using the Nvidia Gamma adjust is actually destructive reducing video quality?

Edit
Answered my own question here (). Apparently CRT's are not linear like the LCD sitting next to it so I need to boast the gamma.
 
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Gamma correction is needed but not 1.6 and more like between 1.05 to I think at max 1.2
The formula is: your_monitor_gamma / desired_gamma
So for reference Rec. 709 which is 2.4 for CRT with gamma 2.6 you need 1.08 correction
For sRGB gamma 2.2 you need in this case 1.18
Though gamma itself is not some fixed value and which should be used depends on many factors such as maximum luminance and lighting conditions and even content displayed and some times there is a need to tweak gamma to get best result.
I have my monitors calibrated to gamma 2.3 and found it perfect for almost all videos and everything with 2.2 being too washed out.

As for what correction should actually be applied it all depends on gamma respone of your monitor and this is influenced by "brightness" and by this I mean "bias" setting that is somehow called "brightness". If you need to use gamma 1.6 then you definitely have it set too low and need to increase it. Best is to have calibration probe and monitor whole gamma ramp but it you have none then for CRT's in dark room your black level should glow a little. Much less than something like IPS LCD at 100-120cd/m2 (which itself is like normal useful value, not too dim, not too bright) but not "pitch black" either.

If your brightness is already near 100% then look for advanced color settings where you can change BIAS and GAIN for three R, G and B guns and increase BIAS.
Such "eye calibration" is not perfect but if you use proper test images it can be fairly good. I always use this site http://www.lagom.nl/lcd-test/black.php (just search "lagom lcd" in google)

Gamma correction (if done within reason) should not cause issues on 980ti because windows has 8bit color and this card has 10bit output so color correction has 2 bits of room and correcting gamma should not cause issues. On 8-bit output like on HDMI/DP adapters any gamma correction will result in some voltages to be duplicated when correcting gamma and loss of fidelity... unless dithering is used which masks all these artifacts nicely and this is what I use cause on my RTX 2070 and Delock DP-VGA adapter I have only 8-bit. Though with dithering every gamma ramp is smooth as butter. Since you do have 10-bit you need not worry about dithering and how to set it.

tl;dr
Increase BRIGHTNESS until gamma correction with which image look correct is between 1.05 to 1.15
 
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Here is a interesting question if anyone knows the answer. This occurs when the monitor is warming up but is more gradual after used for a while. The horizontal size seems to expand and shrink slightly. Sometimes the horizontal expands slightly beyond the borders of the screen and other times it contracts in leaving some gap along the sides of the monitor. I have to go in and readjust the horizontal size to fix this and then later the horizontal size changes again. It doesn't appear to be so bad where I am constantly chasing the horizontal size, only sometimes. I never had an issue where the horizontal collapsed into a vertical line, I would say it never has gone in more than about 1/4" of an inch.

My crude guess is maybe a circuit controlling the horizontal that is linked to the horizontal size adjustment in the menu is becoming a little erratic. It didn't just start doing this but has always been this way since I got the monitor.
2060u Horz.gif


Update
It seems when I start putting hours on this monitor and frequently use it, this issue seems to go away or at least isn't as obvious. As of today the horizontal seems locked in, what a interesting problem

Update
Carefully tapping the frame that houses the circuit board under the monitor doesn't seem to change the issue with what is shown in the GIF image above. I am not so inclined to give it a hard smack as that might cause other issues.
 
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I increased the sharpness of this CRT monitor,

In the service menu there is DBF-H-Amp DBF-Phase DBF-V-Amp. Carefully fine tuning this yielded a very sharp screen at 1920x1440 at 80 Hz. The settings are very picky to get the entire screen sharp, if some values are adjusted a little to far part of the picture will be blurry and the other sharp. I found I needed to turn the contrast all the way up (make the picture bright) when setting this, when adjusted right this will minimizes the fuzziness allowing you to get a bright sharp picture. Apparently there is more to CRT sharpness then just moving the focus control around which I tried.

Update
I had some slight issues adjusting for uniform sharpness across the screen with the contrast all the way up, I found if I decrease the sharpness (brightness) just a little bit the slightly burred areas could be sharpened. A compromise was made between sharpness (brightness) of the picture versus a slight blur when at full contrast (brightest picture), I choose sharpness because I don't often turn up the contrast anyways but I did adjust where blurring during full brightness is minimized.
 
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Here is a interesting question if anyone knows the answer. This occurs when the monitor is warming up but is more gradual after used for a while. The horizontal size seems to expand and shrink slightly. Sometimes the horizontal expands slightly beyond the borders of the screen and other times it contracts in leaving some gap along the sides of the monitor. I have to go in and readjust the horizontal size to fix this and then later the horizontal size changes again. It doesn't appear to be so bad where I am constantly chasing the horizontal size, only sometimes. I never had an issue where the horizontal collapsed into a vertical line, I would say it never has gone in more than about 1/4" of an inch.

My crude guess is maybe a circuit controlling the horizontal that is linked to the horizontal size adjustment in the menu is becoming a little erratic. It didn't just start doing this but has always been this way since I got the monitor.
View attachment 342561

Update
It seems when I start putting hours on this monitor and frequently use it, this issue seems to go away or at least isn't as obvious. As of today the horizontal seems locked in, what a interesting problem

Update
Carefully tapping the frame that houses the circuit board under the monitor doesn't seem to change the issue with what is shown in the GIF image above. I am not so inclined to give it a hard smack as that might cause other issues.
It is some time in the future that I am giving an update to this problem. I managed to resolve this problem, somewhat. Although the horizontal deflection will still move around a bit sometimes, lately it has been locked in more often then not. All I did was simply put hours on this CRT, usage seems to be doing some justice. I think the previous owner I bought this CRT from might have had it in storage for a long time and judging by the yellowed plastic they might have put it in a non air conditioned storage shed. Perhaps the circuitry is slowly stabilizing!
 
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