CameraLightSensor battery drain issue or not? [Android 11, Galaxy M21]

[Helge Nicholson]

Greetings.

I noticed recently my 'Screen on time' is less than 'CameraLightSensor' background time.

How's that possible? Is it still on while the screen is off? I don't use 'Face recognition' or 'Always On Display'.

What keeps it working? I don't want to switch 'Adaptive brightness' off, cause it's useful when the screen is on, but I want to stop the battery drain (or can we call it a drain at the current level?)

Please help me out.

[jimS10]

Whether this article will help in any sort of way but it does mention adaptive brightness turn off or whether you can put it to sleep in the background

[Helge Nicholson]

Hello.

Thanks for the reply.

For some reason, you can't simply optimize the app and put it to sleep in the background. The feature is locked, I suppose.

If so, why does the phone have to use the app in the background? What's going on over there? If 'Always On Display' or 'Face recognition' were on, I could understand, but this is confusing. Is it possible to reach Samsung representatives concerning the issue here? Maybe they can clarify... I read more than just one topic on the subject but none of the articles were giving a clear answer. Once again, 'Adaptive brightness' turnoff is not a solution. Isn't it supposed to be working properly without causing battery drain?

[jimS10]

If you go through your Samsung members app you can get help if you press the icon in the middle and hopefully they might be able to give you a solutions so sorry to hear that you're having issues and I really hope you resolve it as soon as possible

[AshS23ultra]

Unfortunately some samsungs use the front camera as a light sensor in order to change the brightness, turning off all auto brightness will help but unfortunately it will still use it a bit, I had an s20FE which used this feature and returned it, luckily the S20 5G has its own light sensor, I don't know why samsung puts this in cheaper phones it's just penny pinching and ruins the battery life

[Helge Nicholson]

Thank you for your help and support, Jim. I will contact them shortly.

It's not a big deal actually. Usually I charge my phone twice a week, so it's not killing the battery (at least for the time being).

[Helge Nicholson]

Hello, Ash. Thank you for the information, I appreciate it.

So the initial design of using the front camera as a light sensor takes battery life down, but I still can't figure out why does the phone use it when the screen is off. Maybe it has a delay in switching the sensor off? Well, to compare the screen time and the background time, the difference is substantial.

[AshS23ultra]

No problem 🙂 yes I don't understand why either, with auto brightness off and screen off it shouldn't use it, perhaps it uses the camera when it's off to detect if it is in a pocket or dark place who knows, all I do know is its a terrible design and if I buy another samsung with this design it will be returned immediately

[AshS23ultra]

What's worse it you don't know it has this feature till you buy it, I mean the s20 FE which is a higher end phone has it, not cool at all

[Helge Nicholson]

I found another topic on the forum, a user says this wasn't an issue before the system update which was on October 30, 2020.

Before I bought my M21 I read a lot about it, but reviewers did not pay attention to this design peculiarity (though the reviews I read were published before October 30, 2020). Anyway, Samsung does not emphasize some of their phones do not have a separate light sensor, which seems a bit tricky. This is probably a glitch that Samsung doesn't pay attention to (which is weird). I suppose a separate light sensor design is better for battery life, but the front camera being the sensor itself is not supposed to act like that as well! Maybe it has to consume a little bit more than a separate sensor, but there should be a minimum difference.