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Late 08 Macbook Pro screen flickering

Ok, I just played around with it after seeing some flickering on mine.....and to be honest, it looks like the duty cycle from the dimmer showing through.

In case you didn't know, software dimmers work by pulsing the light on and off rapidly, making it seem dimmer. How often they change between on and off is called the duty cycle, and how many times per second the duty cycle repeats is called the frequency. If the frequency is too low, the flicking effect can be seen at low duty cycles. This same effect is responsible for the weird flickering dimmed house lights can have, and the clicking sound some adjustable computer fans make at low speeds.

Which makes me wonder if this is a software fix or not. If it the frequency is controlled by software, it may be possible to send out a firmware update to increase it.
 
J the Ninja said:
Ok, I just played around with it after seeing some flickering on mine.....and to be honest, it looks like the duty cycle from the dimmer showing through.

In case you didn't know, software dimmers work by pulsing the light on and off rapidly, making it seem dimmer. How often they change between on and off is called the duty cycle, and how many times per second the duty cycle repeats is called the frequency. If the frequency is too low, the flicking effect can be seen at low duty cycles. This same effect is responsible for the weird flickering dimmed house lights can have, and the clicking sound some adjustable computer fans make at low speeds.

Which makes me wonder if this is a software fix or not. If it the frequency is controlled by software, it may be possible to send out a firmware update to increase it.
Click to expand...

you're not talking about the auto-brightness are you? because i've set mine to off.
 
J the Ninja said:
Ok, I just played around with it after seeing some flickering on mine.....and to be honest, it looks like the duty cycle from the dimmer showing through.

In case you didn't know, software dimmers work by pulsing the light on and off rapidly, making it seem dimmer. How often they change between on and off is called the duty cycle, and how many times per second the duty cycle repeats is called the frequency. If the frequency is too low, the flicking effect can be seen at low duty cycles. This same effect is responsible for the weird flickering dimmed house lights can have, and the clicking sound some adjustable computer fans make at low speeds.

Which makes me wonder if this is a software fix or not. If it the frequency is controlled by software, it may be possible to send out a firmware update to increase it.
Click to expand...

Yeah well said, that's what I was thinking. As I recently did a lot of research in LCD televsion and a few suffered this problem.

But there is another problem that might be linked, which is hardware lock up (screen goes black and music loops) when gaming in Windows bootcamp.

I've not had time to test this yet on my replacement MBP.
 
J the Ninja said:
Ok, I just played around with it after seeing some flickering on mine.....and to be honest, it looks like the duty cycle from the dimmer showing through.

In case you didn't know, software dimmers work by pulsing the light on and off rapidly, making it seem dimmer. How often they change between on and off is called the duty cycle, and how many times per second the duty cycle repeats is called the frequency. If the frequency is too low, the flicking effect can be seen at low duty cycles. This same effect is responsible for the weird flickering dimmed house lights can have, and the clicking sound some adjustable computer fans make at low speeds.

Which makes me wonder if this is a software fix or not. If it the frequency is controlled by software, it may be possible to send out a firmware update to increase it.
Click to expand...

that would be great if it could be fixed by firmware/software.
 
smokedog said:
Yeah well said, that's what I was thinking. As I recently did a lot of research in LCD televsion and a few suffered this problem.

But there is another problem that might be linked, which is hardware lock up (screen goes black and music loops) when gaming in Windows bootcamp.

I've not had time to test this yet on my replacement MBP.
Click to expand...

Are you using the bootcamp video drivers? if so, don't. I was using them in vista32 and would constantly get hard lockups. I installed the video drivers from laptopvideo2go and they work fine, no more crashes.

However, I still encounter the flicker on low brightness levels in vista too.
 
jgo78 said:
Are you using the bootcamp video drivers? if so, don't. I was using them in vista32 and would constantly get hard lockups. I installed the video drivers from laptopvideo2go and they work fine, no more crashes.
Click to expand...

A tried two different drivers from laptopvideo2go and doesn't make a difference.

There already quite a lengthy thread over at Apple disscssions about this problem
http://discussions.apple.com/thread.jspa?threadID=1767221&tstart=0
 
Have had my new MBP for little under a week now, and playing around in low light situations has caused me to turn down the brightness to levels not used throughout the day; and I have been noticing some flicker.. traces of flicker lets say, that I have not wanted to acknowledge as it would probably mean a fault.. and hassle. The problem seems to kick in when I move turn the brightness to level 2,3 or 4.. then it becomes less noticeable as you move upwards. It's one of those problems that you notice as your browsing and from the sides you get the feeling of a 'shimmer' that is slightly obvious.. but certain its there.

Outside of this the system is perfect.. I am just wondering if I should return it being within the 14 days and take a chance on a new one, or get my money back and buy at a later date.

From level 6 brightness onwards there appears to be no trace - and this seems a comfortable level to use in low light situations that is comfortable.. but I'm still worried the lower levels should have no traces what-so-ever..
 
e3lysium said:
Outside of this the system is perfect.. I am just wondering if I should return it being within the 14 days and take a chance on a new one, or get my money back and buy at a later date.
Click to expand...
Well you paid a lot of money for the laptop, if you can live with the fact it has a fault, then keep it.

I'll put on money on it that you have a 00009C84 screen. I'm interested in the people with 00009C84 screens who don't suffer from this problem.
 
smokedog said:
Well you paid a lot of money for the laptop, if you can live with the fact it has a fault, then keep it.

I'll put on money on it that you have a 00009C84 screen. I'm interested in the people with 00009C84 screens who don't suffer from this problem.
Click to expand...

*raises hand*

9C84, no flickering.
 
smokedog said:
Well you paid a lot of money for the laptop, if you can live with the fact it has a fault, then keep it.

I'll put on money on it that you have a 00009C84 screen. I'm interested in the people with 00009C84 screens who don't suffer from this problem.
Click to expand...

00009C84 is indeed the screen that I have.

I should also add that this is exactly the same problem I have had with my first-generation iPod-Touch; ... operating the brightness in the lower regions results in a sort of fast 'vibration' effect of the screen that your eyes can just make out.. my later purchased iPhone has no such problem in lower brightness settings, therefore people who suggest this issue might be fixed with an update in the future might not wish to ignore the fact it was never resolved for my iPod.

I had already returned a no-problem MacBook 13" as it was a little too small screen-wise for me from the online store.. I should add that my MB 13" had the 00009C85 panel that was fine *but* for the fact that blacks were not as black as they are on the the my MBP 00009C84 (I presume all PROs are better screens) but I am having second thoughts whether or not I should take a chance with another machine 'at the moment' and just get a full refund and wait for a later revisions.. I'll give it a day or two before deciding, but at the moment I'm thinking on getting a refund.
 
e3lysium said:
00009C84 is indeed the screen that I have.

I should also add that this is exactly the same problem I have had with my first-generation iPod-Touch; ... operating the brightness in the lower regions results in a sort of fast 'vibration' effect of the screen that your eyes can just make out.. my later purchased iPhone has no such problem in lower brightness settings, therefore people who suggest this issue might be fixed with an update in the future might not wish to ignore the fact it was never resolved for my iPod.

I had already returned a no-problem MacBook 13" as it was a little too small screen-wise for me from the online store.. I should add that my MB 13" had the 00009C85 panel that was fine *but* for the fact that blacks were not as black as they are on the the my MBP 00009C84 (I presume all PROs are better screens) but I am having second thoughts whether or not I should take a chance with another machine 'at the moment' and just get a full refund and wait for a later revisions.. I'll give it a day or two before deciding, but at the moment I'm thinking on getting a refund.
Click to expand...

yep, same problem with mine 9c84 screen.

Let it be known though, that some people may not be as sensitive to it and not notice it at all. So, for those lucky people, they don't have a problem.

I'm really hoping for some kind of software/firmware fix.
 
Same issue with a 9C85 screen.

Flickering occurs when screen is dimmed to the lowest and second lowest settings. Most noticeable when the harddrive is being written to (e.g. first time bootup / setup screen, installing iWork 08, installing Office 2008). Flickering parallels disk read/write rates.
 
jgo78 said:
yep, same problem with mine 9c84 screen.

Let it be known though, that some people may not be as sensitive to it and not notice it at all. So, for those lucky people, they don't have a problem.

I'm really hoping for some kind of software/firmware fix.
Click to expand...

I think there might be something in what you say regarding the sensitivity aspect in some people, but that does still not mean a "problem" does not exist with those systems. I had the standard MB 13" for around a week before deciding to swap over and in that time I did not notice any form of "shimmer" or "flicker" during this time.

Obviously once you become "aware" of a problem you then begin to look for it even more. I am now of the impression that this fault exists in the higher regions of brightness, it just becomes less noticeable as you move up; masked if you like.

I would suggest people get into as dark-a-room as possible and have their brightness set to maximum and then quickly toggle down to level 2.. and at that point you might be able to understand what some of us here are talking about.

I am 7 days into my purchase and phoned AppleCare up earlier and was merely advised to remove the battery and then hold down the power button for 10 seconds and re-try. Failing that to arrange a Genius showdown.. something I will not be going through as I will request a refund instead if I deem the problem to be unacceptable. I'll give it another day I and see if this battery/reset/thing makes any difference.. but can only test it out later tonight.
 
e3lysium said:
I think there might be something in what you say regarding the sensitivity aspect in some people, but that does still not mean a "problem" does not exist with those systems. I had the standard MB 13" for around a week before deciding to swap over and in that time I did not notice any form of "shimmer" or "flicker" during this time.

Obviously once you become "aware" of a problem you then begin to look for it even more. I am now of the impression that this fault exists in the higher regions of brightness, it just becomes less noticeable as you move up; masked if you like.

I would suggest people get into as dark-a-room as possible and have their brightness set to maximum and then quickly toggle down to level 2.. and at that point you might be able to understand what some of us here are talking about.

I am 7 days into my purchase and phoned AppleCare up earlier and was merely advised to remove the battery and then hold down the power button for 10 seconds and re-try. Failing that to arrange a Genius showdown.. something I will not be going through as I will request a refund instead if I deem the problem to be unacceptable. I'll give it another day I and see if this battery/reset/thing makes any difference.. but can only test it out later tonight.
Click to expand...

I agree. One thing for me though is, my flickering at low brightness goes away after 10 minutes once the computer is turned on, or awaken from sleep. Unfortunately, I've already tried the battery/reset thing and it didn't help me.

Let us know how it goes with the genius, im curious.
 
jgo78 said:
I agree. One thing for me though is, my flickering at low brightness goes away after 10 minutes once the computer is turned on, or awaken from sleep. Unfortunately, I've already tried the battery/reset thing and it didn't help me.

Let us know how it goes with the genius, im curious.
Click to expand...

Having spoken to AppleCare earlier after the power down, battery removal, etc.. I decided to see if this had made any difference and spend a good hour or two with the unit late on (finishing up now) in complete darkness with numerous wallpapers swapped throughout the session (brighter the better) and a single safari browser window set at macforums.. no sooner do I hit the region of 2 on the brightness settings than I begin to notice the shimmering effect (very fast pulsing, sort of refresh rate style) in the open space areas of the browser.. and further noticeable depending on brightness of background, etc; but definitely 'there'

I am just not going down the Genius route and will be ringing returns up tomorrow and explain the reason. Should I be given the option to have the unit replaced I might take a punt, but I doubt Apple work like that in the UK (money back .. re-order when refunded?) ..

I really get the impression as I mentioned in an earlier post that if you have the problem at all then you should be concerned as the 'image quality of text' just not feel as stable as it should do, even on brighter levels. I once again make this assumption on spending several days with the Macbook 13" and noticing no problems at all regarding stability of text, etc. It's very similar to my iPod Touch and iPhone.. the one with the low-brightness flicker problem also has text that is just not as sharp as my iPhone.. so this fast pulsing might be vibrating to the point that regardless of brightness setting overall image is still suffering.
 
Got my 3th Macbook Pro today, guess it is 3th time lucky.

When I first got it, I was certain it was 00009C84 screen due to the extra contrast and brightness. But it turns out to be a 00009C85 hence why it doesn't have the flickering problem. There is still a bit light bleed on the corners but its much more exceptable.

The MBP on the right is the one with the light bleed problem. If you look at the left side of the screen you can see that it is lighter. It's not as noticeable in the photo. But in everyday use your eye is drawn to the bright area.
(Both units are set to 4 brightness and using the same colour profile)


 
smokedog said:
Got my 3th Macbook Pro today, guess it is 3th time lucky.

When I first got it, I was certain it was 00009C84 screen due to the extra contrast and brightness. But it turns out to be a 00009C85 hence why it doesn't have the flickering problem. There is still a bit light bleed on the corners but its much more exceptable.

The MBP on the right is the one with the light bleed problem. If you look at the left side of the screen you can see that it is lighter. It's not as noticeable in the photo. But in everyday use your eye is drawn to the bright area.
(Both units are set to 4 brightness and using the same colour profile)


Click to expand...

using the same color profile for both displays?

one of ur displays are gonna be off (e.g. colors, blacks, whites, etc) seeing that both pannels are from different vendors (e.g. LG 9C84 and Chi 9C85)...
 
EngenZerO said:
using the same color profile for both displays?

one of ur displays are gonna be off (e.g. colors, blacks, whites, etc) seeing that both pannels are from different vendors (e.g. LG 9C84 and Chi 9C85)...
Click to expand...

Both panels are 9C85. But they still look different.
 
Ok, I just bought a brand new 2.5 mbp from Amazon. I plan on it replacing my iMac but so far I'm a little upset about the display.

I have the 9C84 display and I'm comparing it to my late 07 iMac display. Unless, I'm missing something, the MBP's screen is ridiculously inferior to the iMac's. No matter how many times I try to calibrate or load another MBP owners calibration profile, I can't get it to match the iMac's.

The biggest difference I notice is the brightness of the colors on the iMac vs the MBP. The colors are so much more vibrant on the iMac while the MBP just seems washed out. Should this be the case? Are the iMac's displays just naturally superior to a laptop's display like the MBP? If they are not, I'm afraid I have received one of the "crappy" displays I've been hearing so much around here.

If I do have to return it, do I go through Apple or through Amazon? Should I just take it to a local Apple store and ask for a replacement (I could also compare it to the other MBP screens on display)?

Any help or hints on how to help my display would be greatly appreciated. Thanks!!!

Here are some pictures comparing the two, I think the first pic illustrates what I'm talking about best.

web.jpg


web.jpg
 
How do you find out which screen # you have (00009C84 or other)?

EDIT: Never mind...found it here: go to system preferences --> displays --> color --> choose any profile --> open profile --> then scroll down to number 13 --> look at "model"
 
Right, a little update regarding my situation..

I phoned Apple Returns up and was all set to get a full refund when they offered to ship out another unit the following day. Excellent service I must add, and I am now typing this message on the new system that I have literally been using for no more than 20 minutes.. *however* although I still have the same 9C84 panel, thus far (and obviously I am going to need more time to test) I can assure you that the overall impression of surfing and viewing the screen (regardless of brightness) "feels" as it should be. By this I mean that with my previous system my eyes were almost staring "through" the text because "something" was getting in the way causing me to lose focus.. Obviously I was having problems with lower-end brightness flicker and I felt that this was still having an effect in the higher-end brightness levels even though you could not actually see it.. hence losing focus, things not feeling right.

So, so far the replacement has not showed any signs of flicker and surfing and just using the system feels sufficient. I will spend an hour tonight in dark conditions to properly test the panel and make totally sure and look for other screen problems, but so far so good. Not all 9C84 panels have the flicker problem it would seem ..

I just hope I don't regret the positive impressions later!
 
Further update after some late night testing of my new 9C84 unit .. compared against the old problematic 9C84 one; some of the information might be of use to some of you that believe you have the ‘flicker/shimmer’ problem.

Firstly, visiting http://www.lagom.nl/lcd-test/all_tests.php and then scrolling down to “Inversion (pixel walk) test” seems to show the panel with the problems results in shimmering of one of the boxes quite badly - but on my new unit none of those boxes appear to flicker. I am not saying this is in any way related, just an observation between two 9C84 screens.

My new 9C84 is now keeping clarity of text at all light levels and does not appear to be flickering at any of the lower-end light levels.

My vision no longer gets the feeling of ‘staring through’ text and now feels ‘comfortable’ to use.

I would seriously advise anyone who believes they have problems and are within their returns policy to make use of it as the difference is much more than not just having flicker on low-light levels!
 
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