Display "black crush" issue

[Infy_AsiX]

I got a new warranty replacement and just noticed it has "black clipping/crush". Not sure if it's something I never checked to notice before but this replacement display is a little strange too.

Anyway if some people could please check the attached image to see if their display can show the lowest level of black 1. I took the image from an old Note thread. I can only see as low as 6 in Chrome and 3 in Quickpic. Brightness needs to be around at least 50% to allow the lower range to be visible.

If this is a normal issue then it's likely a fault fixable in kernel. I know my last AMOLED a GS3 had this fixed by custom kernel, seems it was a mdnie driver fault https://github.com/AndreiLux/Perseus-S3/commit/9a8a38667bb081fa83c583ef12ad81d7df359066 Don't know if that can apply to us but if it's confirmed a fault I'll look for more recent information. Thanks

 

[JLLE]

With my phone I can see only until level 5 with maximum light but I can guess the number 4 and the lines until the lowest level.

Envoyé de mon ZTE A2017G en utilisant Tapatalk

 

[Infy_AsiX]

With my phone I can see only until level 5 with maximum light but I can guess the number 4 and the lines until the lowest level.

Envoyé de mon ZTE A2017G en utilisant Tapatalk

The numbers should be visible down to 1 when working properly. I've seen it fixed before on the old GS3. Each step down is a gradual step down shade darker. With black clipping there's a sudden drop to black after a particular number.

Sent from my ZTE Axon 7 using XDA Labs

 

[JLLE]

My screen works fine. Perhaps it comes from the picture.
You should try Display tester to check your screen.

Envoyé de mon ZTE A2017G en utilisant Tapatalk

 

[Infy_AsiX]

My screen works fine. Perhaps it comes from the picture.
You should try Display tester to check your screen.

Envoyé de mon ZTE A2017G en utilisant Tapatalk

Display Tester app is where I first noticed it with the similar test under Black saturation. If it's just my device it could be a hardware fault or ROM/Kernel setup. I'm on RR-O with Hellsgate Kernel 3. This current display does have a bad off tint spreading from the bottom right corner. Need more samples to narrow the issue down.

 

[Choose an username...]

I got a new warranty replacement and just noticed it has "black clipping/crush". Not sure if it's something I never checked to notice before but this replacement display is a little strange too.

Anyway if some people could please check the attached image to see if their display can show the lowest level of black 1. I took the image from an old Note thread. I can only see as low as 6 in Chrome and 3 in Quickpic. Brightness needs to be around at least 50% to allow the lower range to be visible.

If this is a normal issue then it's likely a fault fixable in kernel. I know my last AMOLED a GS3 had this fixed by custom kernel, seems it was a mdnie driver fault https://github.com/AndreiLux/Perseus-S3/commit/9a8a38667bb081fa83c583ef12ad81d7df359066 Don't know if that can apply to us but if it's confirmed a fault I'll look for more recent information. Thanks

I talked to a dev about this and he had no idea what i was talking about ? let's hope someone sees this and cares about it

I'm seeing 3 with the latest AEX and full brightness on XDA Labs

 

[Infy_AsiX]

I talked to a dev about this and he had no idea what i was talking about let's hope someone sees this and cares about it

I'm seeing 3 with the latest AEX and full brightness on XDA Labs

Still need samples to narrow the issue. Just searched and found this "Pixel 2 XL vs Samsung S7 edge Black Crush Test at max brightness". So 3 isn't so bad compared to the latest greatest Pixel at 9, but that's LG's first generation P-OLED for you. More relevant is the S7E has our same display down to 1 so the display's evidently capable, just incorrectly set somewhere. Interestingly it's also easy to find complaints of GS8 and GS9 series black crush/gradient banding issues

 

[Infy_AsiX]

Looked up if there's a fix out for the newer Galaxies and it seems not from recent GS9+ discussion. Custom developer work on Samsung display mdnie hasn't progressed in a few generations https://forum.xda-developers.com/showpost.php?p=76532055&postcount=721. I guess it is what it is, at least it's not as bad as some of those recent flagships, those complaints on the GS9+ thread about gradient banding sound terrible and apparently some update improved that but worsened black crush at the same time.

 

[haoyangw]

I'm seeing 3 with the latest AEX and full brightness on XDA Labs

Haha similar, using XDA Free on 50% brightness I can see until 3
EDIT: ok tried with max brightness(auto brightness off) and can confirm still 3 so I guess that's as good as we get xP

 

[Infy_AsiX]

How about official N and O stock? Could it be an AOSP fault?

 

[Choose an username...]

How about official N and O stock? Could it be an AOSP fault?

No, it's normal on every friggin build i tried. I guess it should be possible to fix this with files from the S7E/Pixel XL?

---------- Post added at 04:07 PM ---------- Previous post was at 04:06 PM ----------

My screen works fine. Perhaps it comes from the picture.
You should try Display tester to check your screen.

Envoyé de mon ZTE A2017G en utilisant Tapatalk

You completely sure? It's known to be pretty bad

 

[JLLE]

You know I don't have a very good sight anymore. So, for me the screen is pretty good.
OK I've tried again tonight, and with full luminosity I clearly see until 4 and I can guess the shape of the 3.

Envoyé de mon ZTE A2017G en utilisant Tapatalk

 

[Choose an username...]

You know I don't have a very good sight anymore. So, for me the screen is pretty good.
OK I've tried again tonight, and with full luminosity I clearly see until 4 and I can guess the shape of the 3.

Envoyé de mon ZTE A2017G en utilisant Tapatalk

well, that's the problem. If you watch some video or movie with much black, you'll see this in a lot of places, it's like you see black where there should be gray and it's really unsettling tbh

 

[JLLE]

Ok, I've understood.

Envoyé de mon ZTE A2017G en utilisant Tapatalk

 

[Kingo64]

I am very curious to have the black crush resolved also. I played with all the settings on KCal and none really helped

 

[Choose an username...]

How about official N and O stock? Could it be an AOSP fault?

Have you told any dev about this? NFound, maybe Kranoner, SaintZ, Orden?

 

[Infy_AsiX]

Have you told any dev about this? NFound, maybe Kranoner, SaintZ, Orden?

No I haven't. I figure they have enough on their plate for fixes already. When considering this is exists on multiple devices with no fix. Someone can point the thread out to a dev if they want

Sent from my Xperia Z3C using XDA Labs

 

[Infy_AsiX]

Been watching more videos on my A7 now and decided to revisit this old dead topic. I found similar to other devices discussion on the issue you can workaround a fix using an overlay app called Screen Balance. Using this my cinematic viewing experience is heavily improved in very dark scenes. https://play.google.com/store/apps/details?id=co.uk.quickdoc.screenbalance

As our panel works apparently in the S7E/PXL and for us is only slightly lacking we only need to apply a little fix. Raising "strength" gamma in the app just enough that 1 on the chart shows works well. The free version with fluorescent (neutral no change) balance and 10% strength works on two tested A7's. If going paid pro you can have run on boot and tint/rgb mode that require 3/1% strength respectively instead. The other modes aren't visibly different and aren't necessary to this workaround fix. Hope you enjoy this fix three years after the phone's release

extra note: I watch content at 80% brightness when focusing on fidelity and that's what I tested by

Sent from my ZTE Axon 7 using XDA Labs

 

[Infy_AsiX]

note the overlay leaves scrolling laggy unless you enable Disable HW overlays in Developer Settings.

Sent from my ZTE Axon 7 using XDA Labs

 

[Dodgexander]

Making the changes you describe crushes whites unfortunately, so whilst shadow detail is preserved, whites are not. May just be by aging display of course.