Why do monitor manufacturers limit the minimum brightness? And can firmware binaries be patched by the user?
Posted: 16 Jul 2023, 08:05
Hi, my post is two questions:
I watch a lot of reviews from techless on Youtube because he includes the minimum brightness. And I noticed most monitors have "too high minimum brightness" above 100nits.
Whether the monitor uses PWM or amplitude or both to control the backlight, I understand why the maximum brightness cannot be exceeded (100% PWM or max amplitude that will not fry the LED). But why would the minimum brightness not go down until the blacklight is turned off?
Is there a technical reason why manufacturers don't allow lower minimum brightness? Or is it just "assumed" good enough and hardcoded in the firmware?
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I had this issue with my HP 15 notebook laptop, it was too bright at night and I spent like years trying to find a way to control the backlight. And eventually I did it. (There is an address in memory of the intel HD graphics driver that when set will change the PWM of the backlight to any value below the max.) So now I enjoy the ability to set the brightness as low as I want (even turn off the backlight if I want and keep the color pixels on). But for desktop monitors, the controller controlling the backlight is inside the monitor, so I can't possibly access it just from the computer, it needs to be done from the firmware running on that controller.
So can this be done with desktop monitors? Can I find the firmware binaries, analyze them with reverse engineering tools and find the backlight control range and remove the lower bound limit? AND will the monitor even allow me to install a patched firmware or does it use some sort of checksum/signature enforcement?
I watch a lot of reviews from techless on Youtube because he includes the minimum brightness. And I noticed most monitors have "too high minimum brightness" above 100nits.
Whether the monitor uses PWM or amplitude or both to control the backlight, I understand why the maximum brightness cannot be exceeded (100% PWM or max amplitude that will not fry the LED). But why would the minimum brightness not go down until the blacklight is turned off?
Is there a technical reason why manufacturers don't allow lower minimum brightness? Or is it just "assumed" good enough and hardcoded in the firmware?
------------------------------------------
I had this issue with my HP 15 notebook laptop, it was too bright at night and I spent like years trying to find a way to control the backlight. And eventually I did it. (There is an address in memory of the intel HD graphics driver that when set will change the PWM of the backlight to any value below the max.) So now I enjoy the ability to set the brightness as low as I want (even turn off the backlight if I want and keep the color pixels on). But for desktop monitors, the controller controlling the backlight is inside the monitor, so I can't possibly access it just from the computer, it needs to be done from the firmware running on that controller.
So can this be done with desktop monitors? Can I find the firmware binaries, analyze them with reverse engineering tools and find the backlight control range and remove the lower bound limit? AND will the monitor even allow me to install a patched firmware or does it use some sort of checksum/signature enforcement?