Ambient Light Sensor too sensitive - brightness changing too frequently

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Level 2

328 points

Ambient Light Sensor too sensitive - brightness changing too frequently

Well my 3 day old MacBook Pro 17" (Mid 2009) 2.8GHz, 4GB RAM, 500GB HD 5400RPM computer's screen brightness is adjusting itself quite frequently - and i believe it is too sensitive.

I found this article, which points to a 2008 MacBook as having the same problems - could this actually be the case for my Mid 2009 MacBook Pro as well?

"MacBook (Late-2008) Screen Brightness Undesirably Varies

Still on the topic of unibody MacBook displays, MacFixIt reports that while the new machines' displays are relatively bright thanks to LED backlighting, dimming the displays a little, as many users are wont to do, highlights some problems, namely that the backlight intensity will then not stabilize but persists in a constant state of flux.

According to MacFixIt, Apple employs an algorithm that brightens the display and dims the keyboard in bright light environments, and vice-versa is in dim-light situations, but in the new MacBooks, the ambient light sensor lives at the top of the screen with the iSight camera and its light sensors may be a little too sensitive to minor fluctuations in the ambient light, resulting in screens changing their brightness frequently.

Hopefully, Apple will address this troubling issue with a software patch."

If anyone else is having this issue, i would like to know if this is a known issue with these new Pro's, thank you.

 17" MacBook Pro 2.8GHz 4GB RAM (Mid 2009), Mac OS X (10.5.7),  iPhone 3G S 32GB Black /  iPod Touch 32GB /  15" PowerBook G4 Titanium 1GHz

Posted on Jul 13, 2009 12:33 PM

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Answer 1

khassani

Level 3

952 points

Jul 13, 2009 2:04 PM in response to shcaerp

I misread your earlier comment. The ALS algorithm clearly works for a lot of people. If it's not working for you, then you either have a hardware issue, which you should repair, or an environment that doesn't work very well with the sensor. Maybe Apple can come up with a solution that works in any environment, but I'm guessing it's hard to have an algorithm that works perfectly in every environment.

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Answer 2

tool Author

Level 2

328 points

Jul 13, 2009 2:03 PM in response to khassani

you are absolutely right - i did already know that.

However, that's not the point of the issue, i'm not looking for workarounds, i'm looking to see if this is a known issue with these computers in the hopes that Apple will address it with a software patch.

I did turn off the Automatic brightness feature, but that should not be the fix to the problem. It shouldn't be a problem to begin with.

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Answer 3

shcaerp

Level 1

63 points

Jul 13, 2009 1:51 PM in response to tool

SEE - I told you someone would suggest that!!!!

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Answer 4

shcaerp

Level 1

63 points

Jul 13, 2009 12:37 PM in response to tool

Absolutely having this issue!!! From day 1!! I had to increase the light in my office to get the keyboard to go off. Of course there are those on this forum that will suggest you just turn it off when you don't need it. To them I say - we paid for an ALS for goodness sakes!!!

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Answer 5

khassani

Level 3

952 points

Jul 13, 2009 1:49 PM in response to tool

I have the 13" MBP, and have had no problem with the ambient light sensor. I've found it very useful.

You may already know this, but you can turn it off by going to System Preferences->Displays->"Automatically adjust brightness as ambient light changes."

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Answer 6

shcaerp

Level 1

63 points

Jul 13, 2009 2:23 PM in response to khassani

My suggestion is that Apple could give us the option to adjust the sensitivity of the sensor. As long as I can see the keyboard comfortably, I don't need the backlight to be on. That will vary for most people so you can't have a "one size fits all" approach. My problem is that the backlight is on in what I consider normal lighting. If I increase the lighting my office, it WILL go off which tells me the sensor is working.

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Answer 7

tool Author

Level 2

328 points

Jul 13, 2009 2:32 PM in response to shcaerp

Yes, but when i am in a well lit room, i have the screen brightness all the way up (or most of the way), and it gets dim very frequently in the same well lit environment. I very frequently have to keep turning the brightness back up again.

This is not normal. However, in terms of what you just said about going from a dark room to a well lit room - my machine adjusts that accordingly too - but adjusting it in the same well lit environment very frequently is not normal.

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Answer 8

tool Author

Level 2

328 points

Jul 13, 2009 4:39 PM in response to khassani

If this is the case, then it's a bad design then.

This link that i found before says that the ALS is located in the top of the screen near the iSight camera. If this is true, then that's obviously not a good spot for it. And as it states also from this link, hopefully Apple will address it with a software patch.

http://www.macfixit.com/article.php?story=20081023231829171

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Answer 9

khassani

Level 3

952 points

Jul 13, 2009 4:55 PM in response to tool

I've played around with it, and I think the sensor is to the left of the camera. I think the problem for you may be that it works better with larger radius lights than with a directed light source... a lamp from the back would be blocked by your head. Perhaps Apple would be better off with a sensor on each side of the screen, but I'm not sure this is a simple software fix.

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Answer 10

Jul 14, 2009 6:01 AM in response to khassani

When I'm working in a room and I close the curtains to avoid direct sunlight, every time the curtains move and let more light in the whole brightness changes and then has to change back again - it is a bit sensitive and would be nice if you had one slider to set from very sensitive to environmental changes, to relatively slow to change. That would mean fairly quick changes in the environment would not lead to equally quick changes in the brightness. I think that is a fair comment!

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Answer 11

tool Author

Level 2

328 points

Jul 14, 2009 7:37 AM in response to francoisvlogg

I never had any issues before with my old MacBook Pro with the Ambient Light Sensor being too sensitive. I am in a well lit room, and the brightness of the screen darkens on its own and the same amount of lighting is in the room (nothing to do with the sun going behind the clouds or curtains pulled, etc). If the lighting is a constant same in the room - the screen brightness continually gets darker and i have to keep turning it back up.

I really think there is an issue with this on these new MacBooks (from 2008) to the present, since i found an article in my very first post that suggested it.

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Answer 12

Jul 15, 2009 10:39 AM in response to tool

' Er... Guys - I think this is a very personal thing here... And I think that it appears that the way it is is fine for most people - otherwise you'd see a lot more of these complaints or queries...

' Personally, I quite like it as-is. It's VERY sensitive, yes... But once I've set the screen to about the right brightness for a general locale, it pretty much keeps it there, even with fluctuations in local light. There can be a LOT of adjustments at times, yes - even just with one's head passing between the light source(s) and the sensor - but for me it works great!

' <Shrugs> To each his own I suppose.

~Menageryl

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Answer 13

Jul 23, 2009 4:29 AM in response to tool

' I'm not denying that a slider-like addition to the functionality would be useful... What I am denying is that this is definitively and issue, bug, or fault that exists. That's that. 🙂

' Anyways...

~Menageryl

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Answer 14

Jul 24, 2009 12:18 PM in response to tool

Yes, my 13" is too sensitive. When scrolling a web page, the changing page elements and the light they emitted, reflecting off of my forehead and bouncing back to the sensor, was causing the display to change MUCH too frequently. If the sun went behind a cloud and the display corrected, and then back, that would be useful. As it is, I unfortunately had to turn my ALS off. The problem with Apple allowing users to adjust this is all the people who have staked their identities off of "Apple (Steve Jobs) can do no wrong." To them I say, "Well, Firewire is back!"

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Answer 15

Newton63

Level 1

0 points

Aug 22, 2009 6:17 PM in response to tool

I am having the "issue" too. It is a hair sensitive but nothing I can't live with. I have more issues with the trackpad but that is for a different post. Is the sensor sensitive enough to light to be damaged by direct bright light? I know nothing about them except to guess that it's a photocell and just a component like anything else. The more info on this the better-I appreciate any feedback

Message was edited by: Newton63

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