shamino wrote on 2023-08-12, 08:01:My last CRT was a Sony Trinitron 19", not sure of the model. CPD-G400 comes to mind? Not sure if that's right.
It was absolutel […]
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tauro wrote on 2023-08-11, 19:42:
Could it damage it though? If it is truly harmful then, why is it an option?
I wish I could hack it and use it permanently like this...
My last CRT was a Sony Trinitron 19", not sure of the model. CPD-G400 comes to mind? Not sure if that's right.
It was absolutely beautiful, great contrast and glossy colors. But then the picture started going bad in 1-2 years. Turns out there was a known soldering defect in those monitors that was probably the cause and could have been fixed, but I knew nothing about that at the time.
The monitor had a menu option called "Image Restoration" or "Enhancement" or whatever. It was a one-time option. I used it. The picture was suddenly good again, for a while. Then it got really bad. By the time I got rid of that monitor, the picture had a constant gray smoke color and there were curved red lines all across the screen. It was a total piece of trash at 3 years of age.
To my understanding, that option overdrives the picture tube and ruins it. And as I recall there's no way to turn it off - you do it once and it's permanently in that mode for the rest of the monitor's life.
I think Sony's intent was to reduce warranty claims by adding a destructive option that "forces" the monitor across the warranty finish line. If the tube was ruined after that, it wasn't their problem anymore.
I don't know anything about the option on your monitor or if it will shorten it's life. But don't put too much faith in the manufacturer not to put "risky" options in there if they thought the risk was outweighed by improving their sales.
Nah
The Sony GDM and CPD monitors from a certain age have the issue you mention but I don't believe it's intentional.
Calibration drift happens on all CRTs and I reckon is a cause of many been thrown away which could fixed.
You have to remember a CRT is a hot box with precision resistors and capacitors degrading over time, a small deviation from there desired values causes problems. In addition to solder joints going bad from heating and cooling.
Sony was early to embrace digital CRT chassis and continued to heavily rely on it for calibration and cost saving.
What happens is the analogue components related to G2 voltages go out of spec, the factory digital calibration is now incorrect and drives the monitor too bright
"Image Restoration" is an inbuilt feature to help re-calibrate somewhat and was designed so that image critical applications/users can rely on the monitor for several years over the indended lifespan
Ideally using the factory calibration tool WinDAS is a better fix and even better when in conjuction with fixing the deterioating resistor, capacitor etc
Background on types of CRT 'Chassis' which need to be calibrated in different ways:
Analogue chassis - No digital scan, limited to <40khz, only limited geometry adjustments, often compatabile with 15kHz sources, adjustment and calibration are manual tuning of potentiometers. e.g. early NEC Multisyncs, Sharp, Sanyo, Epson, Mitsubishi PC98, X68000 and CGA monitors
Analogue chassis with digital controls - late 80s, early 90s.. same as above but you get digital adjustment buttons which are actually controlling RDACs and limited memory recall e.g. Mitsubishi Diamond Scan, IIyama MF, Some EGA monitors <~1992
Earlyish Digital chassis - Digital controls, digital scan, digital geometry adjustment with more geometry adjustments available, can scan up 96kHz, cannot sync below 30Khz, memory recall, calibration is done by software but may still be some potentiometers to adjust. e.g. All brands after ~1992 - 1999
Without going into details it is the digital scan component that enables much higher scan capability and geometry adjusments. (With some tradeoffs)
Hybrid chassis - They combine an analogue part to maintain <30Khz horizontal scan rate compatability and a digital part to go above 40Khz. You can see limited adjustments for 15kHz sources but the normal modern adjustments for say 50kHz source. NEC XM29+, some JDM NEC, EPSON monitors etc.
Late Digital chassis - Same as earlier digital chassis but the level of integration is higher, pushing for 130Khz scan rates, very limited adjustment outside of software calibration. Pushing resolution higher and cost lower.
There are of course other things that go wrong such as the flyback deterioration, cathode wear, phospor burn... but on the whole I have more than 30 working CRTs in my collection and all work pretty well. The late Sony's are a bit troublesome to fix because they rely so much on that digital calibration