PG258Q black uniformity fix

[Leonidas44]

So guys i want to highlight how important is to calibrate the gamma of your screen , especially on this one!


In the first pic the screen is at stock "2.2" gamma that is supposed to be calibrated properly from the factory which did not! (Most of the units will not...)
You will notice that:

1) The left side of the panel has a yellowish tint
2) Bottom turns purple
3) Right bottom corner seems to be brighter than the left with extra purple hue
4) Some pixelation-banding in dark areas
5) Washed out colors
So thats not really good , actually thats an instant rma....



But after using Color management to actually correct the gamma and truly make it close to 2.2 , the result turns great:

1) The left side of the panel is no longer yellowish
2) Bottom no longer purple
3) Right corner is the same as left in my human eyes (though camera perceived a minor difference)
4) No pixelation-banding in dark areas
5) Decent colors for a gaming tn panel
Now thats a sample worth keeping!



* Setting the monitor from the osd to 2.4gamma seemed almost right according the color management but still did not provide as good result as CM did.
** Both pics taken by the same camera using iso600 and screen set at 15% brightness which is quite bright for this panel.
*** Please Asus make your workers happier so they can do properly their job.

[namoi]

You said you used color management. What does it means?
Did you used a calibration device or just eyeballed it?

[Leonidas44]

Theres a tool within windows called Color Management , just write it into the search and calibrate the monitor according it.

You dont need a calorimeter for tns just make sure you are looking at the screen as straight as you can (tns have some extreme gamma swift even if you just move slightly) then all you have to do is to make sure that the dots inside the circle are half white (inside) and half dark grey (outside) , you can say that with a quick glance the colors get mixed 😉

This a quick , reliable and cost free way to calibrate your gamma really close to 2.2 gamma even if you dont own a calorimeter.


Out of the 4 units i tried only 2 of them were perfectly calibrated from factory which means that they indeed dont have a good QC and 1 of them had terrible pixelation-banding in dark areas.

This one is very decent after the proper calibration!

[namoi]

Ok i didn't know one could do it. But i own a colorimeter it is why i asked.
So you don't produce a profile for the screen because my experience with calibrating the gamma curve with it lead to bandings which are obviously seen on white to dark gradient.

[Leonidas44]

namoi wrote:
Ok i didn't know one could do it. But i own a colorimeter it is why i asked.
So you don't produce a profile for the screen because my experience with calibrating the gamma curve with it lead to bandings which are obviously seen on white to dark gradient.

Thats weird , the calorimeter is considered way more advanced than this!

I can report exact the opposite this fixed all my color banding-pixelation in dark areas and in general this unit has almost no banding no matter what the color but as stated before the other 2 samples i tested had banding + pixelation in dark areas no matter what i did , you have to consider that the panel lottery is real and no unit is 100% the same!

Its pretty straight-forward , if you want to try it just open the color management (type it in search) then go to advanced tab and press the "calibrate display" after that a tutorial will open , the only thing you have to change is the gamma everything else leave it to stock. 😛

[MarshallR]

FYI here: Only PA's come with factory calibration, no other monitors do.*

[Leonidas44]

MarshallR wrote:
FYI here: Only PA's come with factory calibration, no other monitors do.*

That might be true , however from the moment they put within the OSD the exact gamma values 1.8 , 2.2 , 2.4 "ready" for you they owe to do it.... :rolleyes:

[Korth]

Does this calibration vary from panel to panel - will these particular settings work on every "identical" PG258Q monitor?

Does this calibration drift over time? Will the monitor require periodic recalibration to maintain uniform display quality?

[Leonidas44]

Korth wrote:
Does this calibration vary from panel to panel - will these particular settings work on every "identical" PG258Q monitor?

Does this calibration drift over time? Will the monitor require periodic recalibration to maintain uniform display quality?

Yeap! It varys from panel to panel , every batch have some micro-deference's thats why its never a good idea to install an icc made for another panel , think it like humans , noone ts 100% the same 😉

Well once you calibrate it it will be saved within the windows and it will apply everytime you boot your system so no worries on this one , also it takes about 5 minutes max?! I mean even if something goes wrong in the future or you format your system you can easily re-calibrate it.

The screen itself shouldn't degrade in terms of uniformity , its extremely rare and if it does it will after years of usage 🙂

Sadly almost all tn panels needs calibration so it is not considered a defect either...