[Q] Grayscale? - Nook Color Q&A, Help & Troubleshooting

Hi, thanks for such a wonderful forum.
I want to know if Nook color can be used in grayscale mode for reading e-books.
While on the subject, I'd also like to know if TFT monitors can also display in grayscale. I feel, while increasing battery life it may reduce strain on my middle- aged eyes.
Thanks

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Epic video calibration

Being a home theater enthusiast and calibrating every hdtv I've got me thinking if its possible on android too. And I don't mean the sensitivity or the like. I mean video as in color and brightness. I watch alot of videos and to my experience both are off. Brightness is way too low you can't make out details in dark scenes. Some would say the color is oversaturated... it isn't. Brightness is too low making colors seem this way. A few notches in the brightness scale should take care of it. Anyone know if its possible?
Sent from my SPH-D700 using XDA App
Try manually setting your brightness settings in SETTINGS->DISPLAY->BRIGHTNESS?
I'm a professional video editor and I'm not THAT crazy about having perfect settings for watching video on my phone. Why? I'm usually not in ideal viewing conditions to watch an internet quality video for a few moments on a 4 inch screen with a dinky mono speaker.
Although, I know a few Apple Engineers in Cupertino that are REAL geeks that put bars and tone on their iPhone to just show off.
RushAOZ said:
Being a home theater enthusiast and calibrating every hdtv I've got me thinking if its possible on android too. And I don't mean the sensitivity or the like. I mean video as in color and brightness. I watch alot of videos and to my experience both are off. Brightness is way too low you can't make out details in dark scenes. Some would say the color is oversaturated... it isn't. Brightness is too low making colors seem this way. A few notches in the brightness scale should take care of it. Anyone know if its possible?
Sent from my SPH-D700 using XDA App
Click to expand...
Click to collapse
http://project-voodoo.org/color
It's in vision kernel.
I was thinking of having my Windows desktop show on my Epic's screen using a VNC client. Plop the colorimeter on the Epic, and run the color calibration software on Windows. That would generate an ICC profile for the Epic's screen.
The next question though is how do I get the Epic to apply the ICC profile?
And in case you're curious, my colorimeter measured 7730-7740 K for pure white on the Epic's screen. So yes, it's rather blue.
Yea, nothing personal to the OP, but the colors are most definitely oversaturated. Has nothing to do with the brightness. Samsung, being a display manufacturer as well as a phone manufacturer, has display manufacturer tendencies. One of which is to oversaturate color on a display in order to give a "wow factor" to indiscriminate purchasers who generally assume that brighter and more vivid are better. Every amoled display used on a phone to date has had blooming out the wazoo. Not to mention how ridiculous skin tones look in photographs. I also wish there were a way to calibrate these things. I use a Thunderbolt which is now exhibiting some of the same issues with it's SLCD screen. Although I'm pretty sure that all they did was take the screens used on the EVO and pump up the color saturation. Guessing that's internally what the "S" stands for. The whites are nicer on the thunderbolt though, so at least I get that I guess.

galaxy s II display contrast

Hello.
Anyone else noticed that the display is lower quality than sgs ?
I mean in terms of gamma.
I am a photographer and I was amazed how good the contrast and brightness f the first galaxy was, however this one seems to have way too big contrast, making everythig that is dark much darker, giving a fake and strange appearence.
Also the auto brightness in general is lower than sgs.
Does somebody know if it can be tweaked through a kernel recompile, like sharpness and color in voodoo ?
Go to options-->display-->uncheck automatical screen power adjustme(don't know the exact english term, got it in dutch). I bet it is this again...
Let me know... you're not the first one.
No, it's not that but thanks
It's the actual gamma of the driver I think
However I did notice there is now a "background effects" that can adjust saturation and hue so there is access to the drivers. Maybe a bunch of new effects added there like "classic gamma, normal saturation..."
I came from the captivate, and ran just about every rom that was out there. One of the ubiquitous mods was the color fix. I noticed when I first booted the SGS2 up, the color was off (in relation to my expectations) sure enough in display settings there was an option to change it. Without looking I believe it's called "cinema", which perfectly returned that color richness I loved.
Sent from my GT-I9100 using XDA Premium App
there is something wrong with auto brightness , it doesnt work very well , but its not true that SGS 2 has a lower quality display than sgs , Super AMOLED Plus displays are an upgrade to Super AMOLED. They use a real-stripe subpixel matrix and not pentile - and so has 50% more sub-pixels. The PPI is a bit larger but Samsung will soon make them at much higher resolutions. Super AMOLED Plus displays are also thinner, brighter and use 18% less energy than the older Super AMOLED displays.

[REF] Secrets of the S-AMOLED+ revealed - black crush / battery compromise

While we really like the AMOLED+ display for its deep blacks, it also has major flaws:
- Severe black crush (loss of shadow details in dark scenes) when power saving is disengaged (which is the only way to obtain decent brightness)
- Greenish white, which becomes bluish after a few weeks of operation
- Oversaturated greens
- Loss of brightness after a few weeks of use
- Yellowish areas on the screen produced by the deterioration of AMOLED cells through heat, particularly prominent for gamers and overclockers
I wanted to run a few measurements to better understand what could be done at the software level to alleviate those issues. I am listing my findings below, following which I make a few recommendations to Samung, developers and users of the SGSII.
Findings
1. The maximum light outout with "Auto Adjust Screen Power" is limited
Note that the "Auto Adjust Screen Power" option is different to the automatic "auto-brightness" option. All measurements were made with auto-brightness deactivated and maximum brightness.
After measurements the results are as follows:
- Film Mode: 147cd/m²
- Standard Mode:149cd/m²
- Dynamic Mode: 147cd/m²
The lower value in film mode is due to the limitation of green and blue in film mode, which typically produce more luminance.
The lower value in dynamic mode is due to the picture becoming bright too fast above 50% brightness, there is actually white crush happening, as the Power Saving mode is trying to cap power consumption. This is similar to what is observed on a plasma, where Power Consumption is throttled
2. Disengaring the "Auto Adjust Screen Power" option (this is different to the Auto-Brightness option) significantly increases the brightness output
Not many people suspect the impact that "Auto Adjust Screen Power" option has. Engaging that option provides for much higher bighthness (at the expense of battery life):
- Film Mode: 276 cd/m²
- Standard Mode:285 cd/m²
- Dynamic Mode: 283 cd/m²
This is of course is at the expense of battery life but is still useful when trying to read in the sun. Unfortunately, as we will see later, this has a negative impact on shadow details and is not recommended for film viewing.
3. Light output diminishes though intensive use
The measurements after 3 weeks of use consistently show a deterioration of the maximum brightness over time.
Power Saving Engaged:
- Film Mode: 145 cd/m² (-1.4%)
- Standard Mode:147 cd/m² (-1.4%)
- Dynamic Mode: 145 cd/m² (-1.4%)
Power Saving Disabled:
- Film Mode: 270 cd/m² (-2.2%)
- Standard Mode:278 cd/m² (-2.5%)
- Dynamic Mode: 276 cd/m² (-2.5%)
I will continue to monitor this and post updated results in a few weeks.
4. The white balance exhibits a green push, which progressively becomes more bluish over time
I remember finding the whites greenish when I first got the phone. After 3 weeks, I wasn't bothered that much, they looked more neutral to me. I decided to test again after 3 weeks of use. The results confirmed by observations:
- Color temperature shifted after 3 weeks of use, with the proportion of blue increasing at the expense of green
- The color space after 3 weeks displays less saturated green
White balance at unboxing (green push)
{
"lightbox_close": "Close",
"lightbox_next": "Next",
"lightbox_previous": "Previous",
"lightbox_error": "The requested content cannot be loaded. Please try again later.",
"lightbox_start_slideshow": "Start slideshow",
"lightbox_stop_slideshow": "Stop slideshow",
"lightbox_full_screen": "Full screen",
"lightbox_thumbnails": "Thumbnails",
"lightbox_download": "Download",
"lightbox_share": "Share",
"lightbox_zoom": "Zoom",
"lightbox_new_window": "New window",
"lightbox_toggle_sidebar": "Toggle sidebar"
}
White balance 3 weeks later (blue push)
3. Standard and Dynamic mode have the same color space. Film mode exhibits less green oversaturation
Dynamic/Standard Color Space:
Film Color Space:
4. Film Mode with engaged Power Saving has the best gamma
The dynamic mode has got a skewed gama with a white crush
Film Mode offers better gamma
Disengaging power saving creates black crush
When power saving mode is disabled, the loss of shadow details in dark video sequences becomes even more prominent:
As an example, I am including the gamma curve for the least faulty Film Mode with Power Saving disengaged. The much increased light output we saw earlier is at the expense of shadow details:
Recommendations to Samsung
The display clearly has a lot of potential:
-True blacks
- Large color space
- Very good maximum light output
- Standard Mode gamma is pretty linear
[/LIST]
Unfortunately, these qualities are poorly exploited:
- Gamma is overall too high at lower stimulas. Black crush is happening in any mode, thought at various degree
- White balance is biased toward green and blue, which leads to very high color temperatue. Whites are greenish on first year, evolving toward bluish with increased use.
- The color space could be toned down further. Even in film mode, the greens are too saturated
What Samsung could easily do:
- Further reduce light output in film mode by removing blue and green - this would allow for a color temperature of 65K
- Correct the gamma issues: a simple gamma control under the screen settings allowing to shift gamma incrementally across the whole bightness spectrum would allow very decent results indeed
- Although this has less of a priority in my book, allow a color space with further reduced green saturation.
Recommendations to Android Developers
Develop an app allowing to control:
- Bightness
- Contrast
- Gamma
- If possible for each individual color channel
Such an app would be beneficial to all smartphones on the market!
Recommendations to users
- Use the film mode when watching videos in order to avoid black crush, oversaturation and high color temperature. It is still far from the film standard, but will yield the best viewing experience
- Do not disable power saving mode or you will experience significant black crush. Only do so when viewing in bright environments where contrast is more important than accurate gamma.
Closing thoughts
It is obvious when looking at the numbers, that Samsung have struggled to throttle power consumption on the Galaxy devices while still maintaining brightness comparable to the iPhone 4:
When users reclaim more brightness by deactivating power saving, they indeed get nice peak brightness, but this is at the expense of the darker areas, which lose shadow details in order to limit power consumption.
Many users would be happy with an inbetween solution, with brighness around 180cd/m² but more accurate gamma
thanks for the post, but what secrets were revealed? Quite possible I am too tired (2 in the morning my time), but I only see thorough measurements here
How do you explain color space change and brightness decrease in the weeks you had the phone? Is this how quick the OLED light output degrades?
kreoXDA said:
thanks for the post, but what secrets were revealed? Quite possible I am too tired (2 in the morning my time), but I only see thorough measurements here
How do you explain color space change and brightness decrease in the weeks you had the phone? Is this how quick the OLED light output degrades?
Click to expand...
Click to collapse
You ask what secrets were revealed, but then you ask about one of the interesting findings. OLED displays in general are known to degrade over time, as OLED are especially vulnerable to heat.
The degradation you observe is typically more important in the first few weeks of operation, so there is no need to panic. I will continue to monitor this over time and post updated findings.
Why is green most affected? Green is responsible for most of the light output in any display, because it has a high luminance. This is why Samsung's AMOLED exhibits a green push in the white balance, which no other type screen exhibits. Green oversaturation is very hard to compensate with red, and it would likely reduce battery life. You could see green as an economical way of producing more light output at the lowest power consumtion possible.
Balanced greyscale is only achievable if one is prepared to live with a lower maximum brightness on AMOLED's...or insane battery consumption.
I guess, this is the undisclosed truth that Samsung of course will not publicly admit to, but this is what the measurements reveal when you are used to calibrating displays. Basically, Samsung have had to make compromises in terms of white balance and black crush in order to squeeze some extra brightness out of the battery!
I really have no clue what you just wrote in your OP but you seem to know a lot about displays and color. What I do know about the SGS2 is that is shows color banding in gradients maybe you could explain why that happens, is it a characteristic of the display or a software problem?
eg see these threads:
http://forum.xda-developers.com/showthread.php?t=1102766
http://forum.xda-developers.com/showthread.php?t=1075364
http://forum.xda-developers.com/showthread.php?t=1121840
godutch said:
I really have no clue what you just wrote in your OP but you seem to know a lot about displays and color. What I do know about the SGS2 is that is shows color banding in gradients maybe you could explain why that happens, is it a characteristic of the display or a software problem?
eg see these threads:
http://forum.xda-developers.com/showthread.php?t=1102766
http://forum.xda-developers.com/showthread.php?t=1075364
http://forum.xda-developers.com/showthread.php?t=1121840
Click to expand...
Click to collapse
This probably needs to be solved at the driver level, just like the color gamma and white balance issues. This is related and is something that Chainfire could have a look at. That's his domain of expertise after all...
I only calibrate displays. I am totally unskilled as a developer.
Cool so the display is capable of 24 bits color at least?
maybe u can forward this to supercurio. He has some interest as well as experience developing voodoo color for the last gen samsung phones.
MiG123 said:
maybe u can forward this to supercurio. He has some interest as well as experience developing voodoo color for the last gen samsung phones.
Click to expand...
Click to collapse
Great idea. I posted to Chainfire already, but Supercurio may actually be an even more natural choice.
This has me worried "Greenish white, which becomes bluish after a few weeks of operation"
Is there a bedding in period for oled when they are new, like a plasma tv , that they say to keep the brightness low and avoid frozen images and logos for the first 100hrs until the phosphor settles down.
Hopefully the degradation of the colours will slow down.
EDIT : Also any owners of previous generation oled mobiles, how much degradation of the colours and brightness do they show after a few months/years.
EDIT 2 : It looks like the "Samsung W2400 Special Edition" from 2007 is one of the first oled cell phones , I wonder how it`s display is holding up.
puremind said:
Great idea. I posted to Chainfire already, but Supercurio may actually be an even more natural choice.
Click to expand...
Click to collapse
This is indeed a Supercurio thing
What worries me the most is the left side yellow tint ... and samsung says noting.
I went for S2 because of the SAMOLED+ screen and now I get yellow tint for 600€
Thanks for taking the time to do the testing. I'm used to a calibrated environment (I'm a photographer) and I have to say that I really don't like looking at non-calibrated displays of any kind (usually over saturated, too bright and very obvious colour shifts). If anyone can come up with a way of making proper adjustments to the S2, I would be soooo happy
Nice info. Another dirty secret I'm on the fence about is how power hungry white screens actually ate on amoled screens. Look at the test results I did and how power usage spikes to -900 mA just loading a white web page.
http://forum.xda-developers.com/showthread.php?t=998544
RogerPodacter said:
Nice info. Another dirty secret I'm on the fence about is how power hungry white screens actually ate on amoled screens. Look at the test results I did and how power usage spikes to -900 mA just loading a white web page.
http://forum.xda-developers.com/showthread.php?t=998544
Click to expand...
Click to collapse
I am not surprised. This confirms my theory that Samsung indeed hat to fiddle a lot to contain power consumption within acceptable levels, hence the lack of reds across the greyscale, the black crush we observe without screen power auto adjust and the limited brightness output with it engaged...!
Still, I wouldn't mind having a power hungry but accurate color profile that I can engage only as needed! The screen definitely has the potential. The only question is: at what brightness level is a balanced greyscale achievable. I am betting at around 110cd/m². Considering the true blacks this is very acceptable in dark environments (similar to the best plasma screens), but will not be satisfying under day light conditions, which is most of the time...
Still, I wouldn't mind attempting such a calibration providing the right tool is developed.
Tinderbox (UK) said:
This has me worried "Greenish white, which becomes bluish after a few weeks of operation"
Is there a bedding in period for oled when they are new, like a plasma tv , that they say to keep the brightness low and avoid frozen images and logos for the first 100hrs until the phosphor settles down.
Hopefully the degradation of the colours will slow down.
EDIT : Also any owners of previous generation oled mobiles, how much degradation of the colours and brightness do they show after a few months/years.
EDIT 2 : It looks like the "Samsung W2400 Special Edition" from 2007 is one of the first oled cell phones , I wonder how it`s display is holding up.
Click to expand...
Click to collapse
I believe the degradation is visible after a month-two, we just do not want to believe our eyes.
I think when I first unboxed my phone, it looked so much brighter!
And this is how Samsung is selling us these HyperSuperAMOLED+++ "upgrades" - whenever we look at a new version it is by design looking better than our old previous generation AMOLED
Which firmware did you have in the first test and any firmware changes prior to the last test?
jvidia said:
I went for S2 because of the SAMOLED+ screen and now I get yellow tint for 600€
Click to expand...
Click to collapse
100% same here. Nah, seriously I should've gone for the S-LCD displays. S-AMOLED + is still an unfinished product, under development, unless it comes to the stage of a finished and ready for market product we should avoid it. Thanks to OP for doing some good measurements.
Regards.
kreoXDA said:
I believe the degradation is visible after a month-two, we just do not want to believe our eyes.
I think when I first unboxed my phone, it looked so much brighter!
And this is how Samsung is selling us these HyperSuperAMOLED+++ "upgrades" - whenever we look at a new version it is by design looking better than our old previous generation AMOLED
Click to expand...
Click to collapse
It's hard for me to judge if i had any screen degradations on my captivate since i had it flashed to a new rom quite often and i never had the screen on high brightness (never felt the need to do so)
kreoXDA said:
I believe the degradation is visible after a month-two, we just do not want to believe our eyes.
I think when I first unboxed my phone, it looked so much brighter!
And this is how Samsung is selling us these HyperSuperAMOLED+++ "upgrades" - whenever we look at a new version it is by design looking better than our old previous generation AMOLED
Click to expand...
Click to collapse
Note that not all of the degradation is negative. The alleviates the oversaturated greens, and a bluish greyscale is arguably better than a greenish one.
Also, the brightness is still more than enough and bighter than many laptops even after a few weeks of operation.
I will keep monitoring to see how things develop.
ithehappy said:
100% same here. Nah, seriously I should've gone for the S-LCD displays. S-AMOLED + is still an unfinished product, under development, unless it comes to the stage of a finished and ready for market product we should avoid it. Thanks to OP for doing some good measurements.
Regards.
Click to expand...
Click to collapse
Note that the limitation seems to be the battery rather than the display itself. Also the software is responsible for the presets and lack of controls. When Supercurio comes up with Voodoo for the SGSII, we should be able to rectify most of the issues.
The screen is still excellent for films watched in a dark environment if you keep screen power auto adjust activated.
Bightness can be as bright as on a retina display, yes, but at a high power consumption cost.

[Q] Samsung Galaxy S5 Display (Color Representation)

Hi,
I'm in process of buying Galaxy S5 but have one question to be answered. I've read some mixed reviews regarding the display performance and color representation of the S5 and I couldn't decide who to believe. I've read that cinema mode is the most accurate but also seen some reviews that it isn't as good either. A one of the most recent article on PhoneArena about displays also added to my fears regarding S5 display.
I want to ask from S5 users that is it really the case, does it really noticeable while viewing videos/images or playing games etc. How does cinema mode competes with M8, Z2 etc.
Phonearena have done quite a few blunders recently in their reviews, I don't trust them.
I'd rather go for AnandTech and DisplayMate test results. They have given the S5 very high marks.
Sent from my SM-G900H using Tapatalk
drakester09 said:
Phonearena have done quite a few blunders recently in their reviews, I don't trust them.
I'd rather go for AnandTech and DisplayMate test results. They have given the S5 very high marks.
Sent from my SM-G900H using Tapatalk
Click to expand...
Click to collapse
Thanks for your reply. As you are using S5 can you please tell me your personal experience with display.
I recently changed from a S3 to S5 (G900F). The colors are much more natural than S3's, the screen is a lot brighter and the quality is awesome. It has extremely deep black so deep that you can't distinguish if the screen is off or on! Even in a dark room. The brightness helps when you are outdoors. I live in Macedonia, Greece and here in Greece we have a lot of sunshine through the year, especially now I find it easier to use under sunlight than the S3. Also the white is very good.
So, to sum up:
-Natural colors
-Deep black
-Very bright when you need it.
-Battery savings thanks to amoled technology.
I recommend that you use the phone in person before buying it, from a friend or at a store. This is my personal experience so don't take it for granted. You may end up with different results from me when you use it because everyone has different needs/expectations.
tahirk said:
Thanks for your reply. As you are using S5 can you please tell me your personal experience with display.
Click to expand...
Click to collapse
I really like it but I use it on Cinema mode all the time. I can't stand oversaturation coming from a Nexus 5.
So, would you guys suggest that Cinema Mode is the way to go for everyday use?
drakester09 said:
I really like it but I use it on Cinema mode all the time. I can't stand oversaturation coming from a Nexus 5.
Click to expand...
Click to collapse
Does it gets close to Nexus 5 in Cinema mode?
tahirk said:
Does it gets close to Nexus 5 in Cinema mode?
Click to expand...
Click to collapse
Quite a bit, it's not bad at all.
Cinema mode is the Most natural But is stile Not perfect. With root could be possible To chance color value in The Files with The screen configurations? Chance The code strings. Because it is only a setting like The TV setting preset... But on a TV we Can set manually contrast gamma saturation ecc.. It would be interesting To find Files in The Phone that contains The sets of The screen And Try To change......

[Q] Does selecting different display modes affect battery ?

Hey guys
Was just wondering if setting the display mode to Basic will use less battery than if you set it to Adapt display.
Colours are more vibrant and brighter on Adapt display.
Where as colours on basic are less vibrant and less bright .
AMOLED Cinema is an optimal setting. If you select that and deselect Auto-brightness and set the brightness level to something comforting to the eyes, you may be able to achieve better battery life. Adaptive displays uses CPU power and forces the CPU to analyze GPU algorithms to tone down the display when needed, thus draining some power.
Harshaanl said:
Hey guys
Was just wondering if setting the display mode to Basic will use less battery than if you set it to Adapt display.
Colours are more vibrant and brighter on Adapt display.
Where as colours on basic are less vibrant and less bright .
Click to expand...
Click to collapse
yes i use basic. use that.
zurkx said:
yes i use basic. use that.
Click to expand...
Click to collapse
Same I use Basic.
Colors are most accurate and in fact Basic represents 99-100% of the sRGB color standard.
Other options too over saturated.
Basic reminds me of conventional LCD panels. By the way, stay away from from "AMOLED Photo," makes colors way too warm.
Am gonna stick to Basic .
I tried Adaptive display and battery was drained badly

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