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naphtali · Apr 23, 2008, 11:58 AM

Hi guys

As some of you might know I just went from a 17" Al G4 to a 15" MacBook Pro and I'm really really happy with how everything is!

One thing that's really weird is the screen seems to dim very frequently and without good reason either.

As far as I can tell, the display is uniformly lit, so it's not the usual issue brought up. Turning the ambient light sensor off seems to make things a little better, but I'd like the sensor to be on if possible.

I'm thinking it could be a hyperactive ambient light sensor (remedies?), a totally wonked out sensor, or maybe that the speaker sides (and hence the sensors) are closer to the keyboard on the 15". Or my eyes are playing tricks on me :/

Does anyone else have this problem?

ewiser · Apr 23, 2008, 01:12 PM

You may need to adjust your Power settings System preferences.
Mac OS X 10.1.5: Built-In Flat Panel Display Dims

Xarthan · Apr 23, 2008, 02:40 PM

yeah i've had the same problem, it's pretty annoying. I just turn off the darn sensor myself.

Mastrap · Apr 24, 2008, 11:29 AM

It happens to my new MBP in certain light conditions, when my hands cast a shadow over the sensor.

ewiser · Apr 26, 2008, 10:55 AM

Go to Energy saving in the system prefrences and then to the options tab.
You will see the option to dim screen un check it.

naphtali · Apr 26, 2008, 12:56 PM

Yeah but sadly that defeats the purpose of having the ambient light sensor in the first place? Hopefully there'll be a reliable firmware update

that calibrates the sensor better.

Cold Warrior · Apr 26, 2008, 01:01 PM

At what amount of time is your Mac set to sleep? The screen will dim in advance of sleep - I think at half the sleep time, assuming you've been idle. You can turn off dimming and it won't affect the ambient light sensor.

naphtali · Apr 27, 2008, 03:01 AM

@Cold Warrior - Thanks for the suggestion! I originally set the display to sleep after 15 mins, but just to be sure I tried disabling the dimming altogether. The odd brightness adjustments still occur.

I think there's something seriously wonky with the ambient light sensor because there are times where the screen dims after I place my hands over the speaker grill

I just hope it's a software problem that Apple can fix later on (soon!). Not too keen on sending it in.

Got to get used to the low static over headphones too :/
http://discussions.apple.com/thread.jspa?messageID=6891265

hbeing · Apr 27, 2008, 10:05 AM

Mine does the same thing but I have to cover both speakers. Is that where the sensors are located ??
15" MBP

naphtali · Apr 27, 2008, 10:11 AM

Yep

I've decided to disabled mine for now :/

awal_ink · Apr 28, 2008, 07:34 AM

just tried to reply to this thread, but wasn't allowed to. this is just a test.

slpdLoad · Apr 28, 2008, 07:39 AM

I get the same thing when working at night, apparently the light in the room is right on the edge of the threshold for the ambient light sensors to dim the screen a bit. Every time I go and press the delete key, I guess because of how I type, the shadow over the right speaker grill is just enough to dim the screen momentarily.

awal_ink · Apr 28, 2008, 07:41 AM

not sure how to do this - have only just joined (i see i'm referred to as a fresh-faced recruit. if ONLY!). am i replying to naphtali now? because i just want to say you've clarified the screen dimming problem for me - when i cover the speakers, the screen dims. i've been wondering for days now why the screen does this and getting very pissed off with it and/or thinking there's something wrong with my eyes. my computer is almost brand new and there are lots of things i'm not happy with to be honest, like the way the screen has such a limited hinge mechanism - i like to be able to put the screen almost flat so i can raise the pooter higher and keep keying in from a standing position. ANYway how do i disable the sensor? cheers all.

awal_ink · Apr 28, 2008, 07:50 AM

i have a hunch that if we were working with an external keyboard and a mouse, this screen dimming thing wouldn't happen much, if at all. it's to do with the proximity of our moving hands and forearms to the speakers which must be where the sudden motion sensor is located. i notice in my hardware overview, in 'about this mac', the sudden motion sensor is enabled. i still don't know how to disable it though. and the help menu doesn't help at all about 'motion sensor'. no listing on it. it's infuriating. i also notice that the backlighting in the keyboard is going on and off constantly. seems to turn on when i hit delete and then goes off soon after i return to keying in. what's THAT about. honestly guys, i was happier with my old G3 pizmo powerbook, believe it or not. this one has too many bells and whistles, most of which i don't want or need. sorry to be such a whinger. no doubt i'll learn to love this baby.

Simon · 08:09 AM

Originally Posted by awal_ink

i notice in my hardware overview, in 'about this mac', the sudden motion sensor is enabled. i still don't know how to disable it though. and the help menu doesn't help at all about 'motion sensor'. no listing on it. it's infuriating.

It's not the motion sensor. It's the ambient light sensor. Go to the displays pref and turn off auto dimming. This is pointed out in Mac Help by the way.

awal_ink · Apr 28, 2008, 08:04 AM

Originally Posted by Simon

It's not the motion sensor. It's the ambient light sensor. Go to the dia[lys pref and turn off the auto dimming. This is pointed out in Mac Help by the way.

actually, i've just discovered how to fix it and it isn't the way any of you are advising. in system preferences, under 'displays', you can untick 'automatically adjust brightness as ambient light changes'. now, when i cover the speakers, nothing changes.

awal_ink · Apr 28, 2008, 08:05 AM

Originally Posted by awal_ink

actually, i've just discovered how to fix it and it isn't the way any of you are advising. in system preferences, under 'displays', you can untick 'automatically adjust brightness as ambient light changes'. now, when i cover the speakers, nothing changes.

oh, ok, simon!!!! now i see you HAVE suggested doing it this way. duhh ... sorry.

awal_ink · Apr 28, 2008, 08:19 AM

Originally Posted by Simon

It's not the motion sensor. It's the ambient light sensor. Go to the displays pref and turn off auto dimming. This is pointed out in Mac Help by the way.

think i just posted a reply to myself when i meant to post it to you simon e wise er. it's taking me a mo to get used to the lore of this forum. thanks for the advice.

awal_ink · Apr 28, 2008, 08:25 AM

i hear you loud and red. thanks simon (terribly impressive, the way you can do that, with a red marker pen n'all). but i honestly and truly did work it out for my little old self, a moment before you made it so loud and red. what is this? a form of semi-public humiliation, or what?

tridentinecanon · Apr 28, 2008, 09:29 AM

Mine always dims when I unplug the power cord, regardless of my Energy Saver settings. Very annoying.

SleePyCode · Apr 28, 2008, 07:28 PM

You have to change your Energy Saver settings to fix this. It changes between power adapter and battery for its energy source so these settings change.