Help What does your BLACK screen REALLY look like?

[dhworph]

***warning: do not proceed if you are OCD about minor screen 'defects'...

So, you need to watch this pure black video (pureblack_60sec_1280x720_indeo5.avi, indeo5 compression, 1280x720 resolution), probably on full brightness, in a 100% completely dark room. You may have to wait a bit for your eyes to adjust to the darkness... probably a good 60 seconds or so for your eyes to adjust to the darkness...

It is pure black png, 1 frame per second for 60 seconds, no sound. It plays with MX video player, not the stock ICS video player. You shouldn't see any artifacts, aka blue crush of blue banding, except for the texturing of your screen (at least that's what I think it is).

Look for the texture in your screen. I have a circular splotch just above the soft keys, centered, and a smaller dot on the left side (in portrait). I don't have a camera that is good enough to take a photo of it, as it would take a bit of exposure time..

 

[Deleted User]

Huh, interesting.

So, first of all, my screen is almost perfectly uniform. It's eeever so slightly lighter near the speaker than near the mic.

Second of all, I'm actually surprised at how much light comes off the screen in a pitch black room. I stepped into the network closet, so it was as black as black can be. I hadn't tried that before - given ANY light at all, the screen appears almost perfectly black, but in total darkness, it glows just a tiny little bit. That's not my screen in particular, of course, just AMOLED screens in general.

Cool.

 

[Jahmakan]

Characteristic of AMOLED screens apparently, 'cause I have the same effect on my unlocked GSII.

 

[dhworph]

hm... maybe mine is one of the ones with a bit more more inconsistency... There is definitely two distinct small black blotches + the typical flyscreening (of coarse this is all very difficult to see). You really have to spend some time letting your eyes adjust...

I'd like to get some more opinions... I'd be happy to adjust the video to whatever resolution and color, if someone requests too...

 

[Rons]

does this still work?

 

[mttfrog13]

yeah this "defect" if it can even really be called that is visible on the gnex and droid razr although it seemed much worse on the droid razr to me. It is in fact not visible on the sgs I and II super amoled+ screens. The screens on the SGS screens are basically a true back and do not emit much life is any at all. In a pitch black room, with a black image on the screen, you wouldn't even be able to tell the phone is on at all.

 

[Deleted User]

Incidentally, this is not a true "black screen" - or, at least, the Nexus doesn't display it as such. I was amazed at the amount of backlight coming from the screen on an AMOLED but last night I noted that the black area around the navigation buttons is MUCH darker.

So, either the video isn't true black, or the video player isn't rendering it properly - but while it's a dark screen, it's not entirely black.

 

[dhworph]

Well... Another thing to try is dead pixel test black, but that leaves the softkeys on. I suppose you could kill the sysbar service (I can't remember where I saw that, but I saw a restart option for it somewhere that killed the notification bar and softkeys, and it took about 30 sec for them to reappear. Then you could compare the dead pixel test black to this video's black.

I guess the questions are: (1) does the amoled black still use some power and emit some light? --- Also noLED is a neat notification program that supposedly only lights certain pixels. could compare that black to other blacks.

and (2) Is it possible to get a true black in a video, if a true black exists? i.e. having a black in a video that actually doesn't power the black pixels... but maybe switching them on/off would be less power efficient than having them at the lowest possible brightness.

I'll try to test some other blacks tonight to get another comparison. Also, this video is compressed with indeo5, I'll compare it to the uncompressed version to see if there is any difference in brightness.

*another idea for a black test would be to make the boot animation pure black pngs, and watch that in a completely dark room to see how different it is from this video.

 

[sooper_droid12]

Why does it need to be video? Why can't you just display an absolute black image to see light leakage? I do this on HDTVs to show how backlighting is not always uniform?

 

[dhworph]

Why does it need to be video? Why can't you just display an absolute black image to see light leakage? I do this on HDTVs to show how backlighting is not always uniform?

A video is the only way I know how to get completely black display (i.e no softkeys or notification bar). Plus I'm wondering if black behaves differently in video players as compared to the blacks displayed in other apps.

If someone else knows a better way to get a completely black screen (other than turning it off), please chime in!

 

[dhworph]

In my opinion, the brightness of this pure black video is the same as with dead pixel test and noLED.

A relevant thread on xda: screen blackness - xda-developers

It seems there is a minimum voltage applied to blacks. It may be built into the OS software though, rather than a manufacturing thing though.

 

[Deleted User]

That may be - and is why I assumed that the minor glow from the screen during this video was simply normal - but there is clearly some way to closer to true black.

Here's a test for you - go into the clock application, and then tap a blank area of the screen. The screen dims and ostensibly goes "black." However, the notification and navigation bars a very clearly darker than the rest of the screen. That's about the level of black that the video produces.

If you pull up a black image in the web browser or the gallery, you'll see that it's actually the same level of black as the nav bar or the notification shade.

If you view each in a completely black room, you'll see that there is still a little bit of glow from a black image pulled up in the gallery, but noticeably less than the video.

 

[dhworph]

star this google code issue and pass it along (Issue 23862: Galaxy Nexus display is very poorly calibrated: http://code.google.com/p/android/issues/detail?id=23862). I couldn't find another google code issue along the same lines. If you know of other google code issues that are similar or the same, please post links to the here too.

 

[butternutz]

LMAO here we go again people and there crazy minds. When in dark playing hide and seek and look at my phone black looks not so good haha. J/K.

 

[dhworph]

I replaced my boot animation with full res #000000 pngs. And powered down waited for my eyes to adjust... booted up closing my eyes till the google logo disappeared... man i can tell you that thing is BRIGHT!

 

[Deleted User]

star this google code issue and pass it along (Issue 23862: Galaxy Nexus display is very poorly calibrated: Issue 23862 - android - Galaxy Nexus display is very poorly calibrated - Android - An Open Handset Alliance Project - Google Project Hosting). I couldn't find another google code issue along the same lines. If you know of other google code issues that are similar or the same, please post links to the here too.

Well, I kind of expect a certain amount of glow coming from the screen even when set to completely black. I'm guessing the variability between "true" black (i.e. totally off) and a black image (i.e. the current small glow) is not infinite and they keep a minimum voltage to prevent a "jump" between true black and the minimum actual black level.

That's totally speculation, incidentally, just thinking out loud.

So the issue isn't that the screen glows a little (the overall screen calibration), what I'm observing is that the difference between a video playing black, and a displaying a black JPG, is noticeable.

 

[techno_techie]

I have the light leak, but I have deep black black dots ALL OVER the screen. They are only visible on the black screen using a pixel test tha eliminates the soft key bar. It looks like a speckled egg with these tiny dots of different sizes. I just want someone to say this is normal because I don't want to have to replace the phone. I'm concerned this is a fabrication issue, not a calibration issue. I'm going to see if I can take a long exposure photo of it.

 

[dhworph]

I have the light leak, but I have deep black black dots ALL OVER the screen. They are only visible on the black screen using a pixel test tha eliminates the soft key bar. It looks like a speckled egg with these tiny dots of different sizes. I just want someone to say this is normal because I don't want to have to replace the phone. I'm concerned this is a fabrication issue, not a calibration issue. I'm going to see if I can take a long exposure photo of it.

What pixel test are you using? I couldn't find one that eliminates the softkeys.

 

[techno_techie]

It's called lcd test in the market. The directions use the black color, don't touch the screen, soft keys roll off. My largest black dot is just to the left of the tasks soft key.

 

[dhworph]

It's called lcd test in the market. The directions use the black color, don't touch the screen, soft keys roll off. My largest black dot is just to the left of the tasks soft key.

thanks, it works good... gives me hope that I'm not crazy... someone else is able to see the screen "texture" when it's pure black!

 

[techno_techie]

Okay - I have a picture taken at long exposure. Tell me what you think - after seeing it, I think I should definitely return it!

DSC_0040 | Flickr - Photo Sharing!

 

[fortesquieu]

Okay - I have a picture taken at long exposure. Tell me what you think - after seeing it, I think I should definitely return it!

DSC_0040 | Flickr - Photo Sharing!

That looks gross. Can you exchange that phone?

 

[jamisont]

That looks gross. Can you exchange that phone?

im afraid u'd get same type of dark spot on all amoled displays.
as far as i know its not a defect unless its really large enough to see it in normal use.

 

[techno_techie]

I did see it during normal use. I was watching Netflix in a dark room.