Macbook pro brightness keep changing

I did turn off "automatically adjust brightness as ambient light changes"

It keep changing. Last night before before I shut it down, it was at about 75%. This morning when I turn it on, 100%. After I put it to sleep midday, it went to 50%.

Why does it keep changing?

I'm using coloreyes display pro for calibration. Does this software change the brightness automatically?

thanks

Try zapping the pram and then setting it, shutting it down, restarting it and see if it sticks.

sorry, don't quite understand zapping the pram

Sorry, try this: http://support.apple.c​om/kb/ht1379

I have the same problem. The brightness is the only setting that changes - apparently randomly. Not sure I'm too excited about following the instructions in the link posted above. It's irritating, granted. But for now, it's not irritating enough that I want to hassle with it...

Just to get the obvious culprits out of the way, are you aware that the MBP has a sensor that automatically changes the screen brightness when the ambient lighting conditions change? This can occur even when your shadow is cast on the screen.

EDIT: Sorry, I have now read your post (always advisable; my bad) and see you have ruled this out.

jsvphoto wrote in post #10983277
I have the same problem. The brightness is the only setting that changes - apparently randomly. Not sure I'm too excited about following the instructions in the link posted above. It's irritating, granted. But for now, it's not irritating enough that I want to hassle with it...

I guess I don't understand what the hassle is? I mean you restart the computer while holding down some keys. How hard is that?

I had the same problem too. It seemed to happen when I've unplugged my laptop from power and after 20 minutes the screen will dim (as I have it set to do). Then, if I plug back into wall power the settings for Power Adapter, for some reason the dimming will start occurring even though I have it set not to. The only way I could figure out how to stop this was to go into Energy Saver > Battery tab > remove check from "Slightly dim the display..." and remove check from "Automatically reduce brightness...". I have the Display Sleep set at 5 minutes and Computer Sleep at 15 minutes. After doing that my brightness bar has remained locked at 100%.

Todd Lambert wrote in post #10984319
I guess I don't understand what the hassle is? I mean you restart the computer while holding down some keys. How hard is that?

Trusting the advice of someone on the internets is guaranteed to end in goodness, right?

So the "hassle" part comes along with preparing myself for the real possibility that the advice might end up in changes to my computer that I don't know how to correct. Meaning I would want to research the issue more thoroughly before implementing your advice.

No offense is intended. I'm not insinuating that you're inherently untrustworthy, only that I don't know you from Adam and am therefore unwilling to take your statement as unerring fact.

Hey, no offense.... I understand.

I'm only giving advice that has helped me in the past. I've owned more Apple laptops than most people own entire computers. I made a suggestion and linked to it as found on the computer manufacturers website.

As for resetting the pram memory, it's a pretty benign operation. It's simply overwriting "temporary" settings. It's basically flushing out things - some that you'll need to reset like your volume settings, etc..

Anyways, it's great that you ask or even do research about these things, most people don't.

Resetting PRAM and NVRAM is easy. Matter of fact, it's a good idea to do it after an OS X system update (e.g. 10.6.1 to 10.6.2).

Hi, did any one find a solution to this problem?
I calibrate with a spyderpro and today spent over an hour processing in lightroom only to realise my brightness setting had randomly changed and all of my processing was too dark.

system preferences/Displays/ and uncheck Automatically adjust brightness as ambient light changes.

archie wrote in post #11455378
Hi, did any one find a solution to this problem?
I calibrate with a spyderpro and today spent over an hour processing in lightroom only to realise my brightness setting had randomly changed and all of my processing was too dark.

And you've already tried this -> Energy Saver > Battery tab > remove check from "Slightly dim the display..." and remove check from "Automatically reduce brightness..."

There's always a logical reason things happen with computers, you just need to track down what's causing it.

hi peeps,
I had unchecked all of those features before chiming into this thread.
The only solution I have found is calibrating with the monitor brightness set to full.
cheers