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TV backlight compensation (2020)

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Re: TV backlight compensation (2020)

#91

Post by jerf »

Tade0 wrote: post #85

I damaged my laptop's screen by leaving it running at 100% CPU with the lid closed for too long(not my intent - that was "sleep mode"). The adhesive keeping the LCD layers came off, creating a diagonal striped clouding pattern. I was meaning to do something similar to the author[0], but couldn't make time and just used this opportunity to buy an external screen. I'm glad someone put in the work so that now I may be a…

"The adhesive keeping the LCD layers came off, creating a diagonal striped clouding pattern."

Oh, is THAT what that is. I have an ancient laptop where the screen is failing that way. Was trying to figure out what on Earth could produce perfectly diagonal streaks in an LCD! Though I'm still not quite sure how that connects; is the tape oriented diagonally?

Re: TV backlight compensation (2020)

#92

Post by lesuorac »

franky47 wrote: post #44
EZ-Cheeze wrote: post #41

Earlier quoted context omitted.

I'll do it when I can just tell the computer to do it - maybe 2024 It will be interesting to rewatch movies with all the faces blanked out - they're eye-magnets that prevent you from noticing other details, for example in body language

Funny how recent developments in AI have warped our comprehension of what is easy to ask to a computer vs what is hard. Obligatory related XKCD: https://xkcd.com/1425

Besides the fact that GPS already exists, it seems like it would take longer (~20 years) than the 5 years claimed to detect birds.

> The GPS project was started by the U.S. Department of Defense in 1973. The first prototype spacecraft was launched in 1978 and the full constellation of 24 satellites became operational in 1993

https://en.wikipedia.org/wiki/Global_Positioning_System

Re: TV backlight compensation (2020)

#94

Post by MayeulC »

washadjeffmad wrote: post #67
jagged-chisel wrote: post #55

Earlier quoted context omitted.

Is that 35 minutes spent collecting input, or calculating the LUT?

I imagine the process is Capture > Analyze > Generate > Apply > Repeat until all test images are within bounds and color matched, not stage 1: capture, stage 2: calculate, done. That's how it worked for our projection, at least.

Well, you could capture once over a range of inputs to get a much better initial first guess too!

Re: TV backlight compensation (2020)

#95

Post by aidenn0 »

drumdude wrote: post #21

I do this for a living. Sony digital cinema projectors use a type of LCD panel (SXRD) where the uniformity drifts over time. A special camera takes about 35 minutes to create a LUT to restore the projected image to a uniform white.

Is SXRD just Sony's name for LCOS, or is it something distinct?

Re: TV backlight compensation (2020)

#96

Post by BoorishBears »

autoexec wrote: post #52
BoorishBears wrote: post #36

Earlier quoted context omitted.

My XDR has been pretty flawless, and on the less exorbitantly priced end, I've had good experiences with a few business oriented IPS models (most recently the Samsung UR55). My main gripe is gaming monitors seem to be consistently the worst panels they can get their hands on. It seems like they realize gamers will put up with a lot of garbage in exchange for raw "power" and take full advantage of the fact. I'm 99% su…

If you fill your entire screen with nothing but a single solid color (try #FF6400) does it show up correctly? That is, without any gradient or areas of the screen where the color appears darker or lighter (especially around the edges or in the corners?). I've yet to find a modern monitor that doesn't have a problem with that basic test, which is pretty disappointing considering accurately representing a single color…

Yes, I know what backlight bleed is...

I've probably owned something like 15 monitors in the last 5 years, the XDR may not live up to the 25k reference monitor dreams, but no mere mortal would be able to drive one anyways.

Re: TV backlight compensation (2020)

#97

Post by moffkalast »

londons_explore wrote: post #47
speedgoose wrote: post #38

Earlier quoted context omitted.

How did you manage to find the issue?

I noticed the screen only died when playing videos and always died at the same point if I rewatched a video. Notably, greyscale videos never caused the issue. Then I went through a video frame by frame to get to the frame it died on. Then I erased parts of the frame to find which part caused it. Eventually I found that if the red or blue pixel in the 481st column and the green pixel in the 482nd column have a differe…

That is some top tier investigating and persistence, hats off. I would've used the excuse the upgrade the monitor lol.

Re: TV backlight compensation (2020)

#98

Post by nmilo »

tgsovlerkhgsel wrote: post #13
adrianN wrote: post #8

Earlier quoted context omitted.

Why create waste when it's not necessary?

If you're not doing it as a hobby, the one-off effort put into repairing an item (or in this case, engineering the correction) is also "waste". If you want to dedicate that time to improving the planet, avoiding the waste of one TV is likely not a better use of your time than e.g. fixing some bug in some popular open source software that causes it to be less efficient. Let's say you make a change to Firefox that make…

What a ridiculous premise. The value of your time does not come in some sort of interchangeable unit where 1 hour of TV repair is comparable to 1 hour of Firefox bug-fixing. Realistically, if the author decided to get a new TV, he would not spend that new-saved time trying to make up for the environmental damage he caused by throwing his old TV out.

(And who is even to say your bugfix would save power? It's not like Firefox has a power-usage detector in their CI pipeline.)

Re: TV backlight compensation (2020)

#99

Post by batch12 »

nmilo wrote: post #98
tgsovlerkhgsel wrote: post #13

Earlier quoted context omitted.

If you're not doing it as a hobby, the one-off effort put into repairing an item (or in this case, engineering the correction) is also "waste". If you want to dedicate that time to improving the planet, avoiding the waste of one TV is likely not a better use of your time than e.g. fixing some bug in some popular open source software that causes it to be less efficient. Let's say you make a change to Firefox that make…

What a ridiculous premise. The value of your time does not come in some sort of interchangeable unit where 1 hour of TV repair is comparable to 1 hour of Firefox bug-fixing. Realistically, if the author decided to get a new TV, he would not spend that new-saved time trying to make up for the environmental damage he caused by throwing his old TV out. (And who is even to say your bugfix would save power? It's not like…

Not to mention the time spent shopping, fuel spent delivering, time spent setting up and configuring...

Re: TV backlight compensation (2020)

#100

Post by CamperBob2 »

moffkalast wrote: post #97
londons_explore wrote: post #47

Earlier quoted context omitted.

I noticed the screen only died when playing videos and always died at the same point if I rewatched a video. Notably, greyscale videos never caused the issue. Then I went through a video frame by frame to get to the frame it died on. Then I erased parts of the frame to find which part caused it. Eventually I found that if the red or blue pixel in the 481st column and the green pixel in the 482nd column have a differe…

That is some top tier investigating and persistence, hats off. I would've used the excuse the upgrade the monitor lol.

Or replace the 30-cent capacitor that's likely causing it.
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