Brightness Hack? Lowering Brightness past manufactured intended?

Discussion in 'PS Vita - Hacking & Homebrew' started by the3dsguy, Sep 3, 2016.

  1. the3dsguy
    OP

    the3dsguy GBAtemp Regular

    Member
    226
    83
    Dec 1, 2014
    Canada
    I like playing my ps vita on my bed at night with the lights turned off. I find that it's still pretty bright.

    Is there like a hack that can even lower the brightness, lower than manfactured intended?

    Im sure im not the only one wondering this.
     
  2. Sasukesama

    Sasukesama Member

    Newcomer
    38
    4
    Apr 29, 2016
    I need something that overbright the screen
    like the brightness PSP plugin
    I can't see anything outside especially in the sun
    OLED
     
  3. FAST6191

    FAST6191 Techromancer

    pip Reporter
    23,841
    9,728
    Nov 21, 2005
    United Kingdom
    I have not looked into the vita hardware and means it uses to achieve brightness control, though I would be surprised if it is not some kind of LED brightness controlled with PWM. If it is a separate hardware control then chances are slim without busting out a soldering iron, though there might be some undocumented stuff/headroom. If the OS/background processes generate the pulse then you have scope for something. Be aware that if you go too low with PWM you start to see flicker, indeed if you have a camera that can record fairly quickly then get a blank screen, drop the brightness and then you might see it there. It is the same for brightness increase, though a lot of things will operate at a 100% duty cycle for the PWM and going over that will see you overvolt (if that is even possible) or something else that probably will involve a soldering iron. With OLED stuff I am not sure what type of OLED they use, big boy OLED works by having the pixels generate their own light and that might alter the scope for things, if it is just LCD with an OLED backlight then it should be like above.

    The forest for the trees method is find youself a bit of sticky back plastic (or tape it if you are playing the cowboy) but have it slightly shaded/tinted. The type of plastic you choose might trouble the touchscreen but I reckon that stuff people use to put on their windows should do and does readily come in tinted form.
    Depending upon what causes the outside issue you might have some scope for something here, though it might involve playing with polarising filters. Quick test if you have a set of those 3d glasses for 3d cinemas then they have circularly polarised lenses (would have preferred straight polarised for a test but those glasses are an easy thing for people to find). Stick them on and rotate your head a bit.
     
    hobbledehoy899 likes this.
  4. hobbledehoy899

    hobbledehoy899 Conniption Master

    Member
    2,763
    4,563
    Nov 13, 2015
    United States
    Kernel Version: Linux 4.14.5-1-zen
    Pulse-Width Modulation
     
  5. the3dsguy
    OP

    the3dsguy GBAtemp Regular

    Member
    226
    83
    Dec 1, 2014
    Canada
    you lost me at hello, i guess its a bit difference with phones, where you can get a filter app
     
    Last edited by the3dsguy, Sep 3, 2016
  6. BORTZ

    BORTZ You get a hat, and YOU get a hat!

    Supervisor
    GBAtemp Patron
    BORTZ is a Patron of GBAtemp and is helping us stay independent!

    Our Patreon
    11,754
    14,905
    Dec 2, 2007
    United States
    Pittsburgh
    I have wondered this myself. Luckily it's not as bad as the PSP volume issue. The lowest setting was not very quiet and the loudest wasn't very loud haha
     
    hobbledehoy899 likes this.
  7. FAST6191

    FAST6191 Techromancer

    pip Reporter
    23,841
    9,728
    Nov 21, 2005
    United Kingdom
    The less technical version it is then.

    Then and now I have not read up on the hardware so going for the more theoretical approach as it is still a screen on a mass produced device and those I do know.

    Doing it in software is theoretically impossible, however whether the vita is hacked enough or there are options for it I do not know.

    LEDs do not do the best with different voltages, though for some it is an option, so in cases of variable brightness it is often so called pulse width modulation (PWM) which is used. It works by flicking the power on and off many many times a second. If you have ever turned a LED off you might have seen it ramp down quickly rather than just turn off instantly, you abuse this feature with PWM and do it right and you keep it in a perpetual state of dimming down. This dimming could be controlled by the vita at all times or it could be kicked to a secondary device (the DS lite does this and many other things which can't be bothered to handle it at CPU level do too). Either way depending upon what goes it might not be possible in pure software and it might have seen you then have to bust out the soldering iron, which most are reluctant to do.

    If software is not possible then you do have a far more basic option. You can either put shades on the source or shades on your eyeballs. If wearing shades in a club makes you a complete bellend then wearing shades in bed, especially if you are wearing socks as well, is not better so that is not really an option. To that end put shades on the screen. You do this by getting a piece of tinted plastic, possibly like the thin vinyl you use on windows to give them a bit of a tint, and putting it over the screen.
    In the case of the second post then I suggested a polarising filter as it might well be that the sun (no particular polarisation) vs the screen (possibly a certain polarisation, not sure what the vita is) could block out much of the reflection/sunlight but leave the screen. As a lot of people have nice polarising filters in their houses thanks to those reald3d cinema glasses.
     
  8. Stwert

    Stwert Advanced Member

    Newcomer
    77
    22
    Jan 6, 2015
    Scotland
    Not really my area of expertise but it should/is possible to vary the brightness of an OLED screen by adjusting the voltage/current to the display driver.

    But it's really not just as simple as dropping it down, several factors have to be taken into consideration.
    These documents aren't too bad for getting a basic understanding of the effects of power adjustment in relation to the brightness and effects on lifespan of OLED panels.

    Osram

    Power Electronics