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Does this make your (MBP) screen flicker (like crazy)?

other said:
But like someone said, it may be related to the GPU and not the screen.
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The fact that this problem occurs with both LG and Samsung panels also supports the theory that it's the GPU that's causing the problem -it would be quite surprising that panels coming from different manufacturers suffered from the very same anomaly, unless it is a general feature of the LED-based technology, which I certainly doubt.
 
G.F. said:
The fact that this problem occurs with both LG and Samsung panels also supports the theory that it's the GPU that's causing the problem -it would be quite surprising that panels coming from different manufacturers suffered from the very same anomaly, unless it is a general feature of the LED-based technology, which I certainly doubt.
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You're right. What puzzles me is all the people (for example, Cybergypsy) who claim that there is no flicker present on their SR MBPs.
 
Powerbook 15'' 1.5ghz here.

I only see an off-black blank image. No grey lines, no pattern, nada. Tried at full zoom and full screen in firefox.

I gather that there are supposed to be grey lines in it? Did someone say it shows their terminal window overlay on it?

I can understand it flickers on some machines and not others. I don't understand how come some of us are apparently seeing completely different images.
 
RedTomato said:
Powerbook 15'' 1.5ghz here.

I only see an off-black blank image. No grey lines, no pattern, nada. Tried at full zoom and full screen in firefox.

I gather that there are supposed to be grey lines in it? Did someone say it shows their terminal window overlay on it?

I can understand it flickers on some machines and not others. I don't understand how come some of us are apparently seeing completely different images.
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Make sure you're downloading the full image and not the thumbnail (ie. don't right click on the thumbnail and choose "Save to...").
 
other said:
Make sure you're downloading the full image and not the thumbnail (ie. don't right click on the thumbnail and choose "Save to...").
Click to expand...

I opened the full image and zoomed in with a firefox zoom utility, and nada.

But now I tried actually downloading the thing (couldnt be bothered before) and opening it in preview. Yup got the the lines. They're only visible when zooming in extremely close and when zooming out quite far away, at certain zoom levels. No flicker yaay. I suspect on some MBPs, there's a resonance frequency on the screen circuits, and some people are hitting it with this at certain levels of zoom.
 
Dithering

Dithering and Frame Rate Control (FRC)


TN Film screens are traditionally more economical than other technologies. In fact, they only display 64 red, 64 blue and 64 green shades. The maximum amount of colours achievable from liquid crystal rotation alone is 262 144. In order to reach 16 million colours and above, panel manufacturers commonly use two technologies: Dithering and Frame Rate Control (FRC). These terms are often interchanged, but strictly can mean different things.


Spaital Dithering - The dithering method involves assigning appropriate color values from the available color palette to close-by pixels in such a way that it gives the impression of a new color tone which otherwise could not have been created at all. In doing so, there complex mappings according to which the ground colors are mutually assigned, otherwise it could result in color noise / dithering noise. Dithering can be used to allow 6-Bit panels, like TN Film, to show 16.2 million perceived colours. This can however sometimes be detectable to the user, and can result in chessboard like patterns being visible in some cases (i.e. the 'graininess issue' complaint from Apples MBP customers).


Frame Rate Control / Temporal Dithering - The other method is Frame-Rate-Control (FRC), also referred to sometimes as temporal dithering. This works by combining four colour frames as a sequence in time, resulting in perceived mixture. In basic terms, it involves flashing between two colour tones rapidly to give the impression of a third tone, not normally available in the palette. This allows a total of 16.2 reproducible million colors. Thanks to Frame-Rate-Control, TN panel monitors have come pretty close to matching the colors and image quality of VA or IPS panel technology, but there are a number of FRC algorithms which vary in their effectiveness. Sometimes, a twinkling artefact can be seen, particularly in darker shades, which is a side affect of such technologies. Some TN film panels are now quoted as being 16.7 million colours, and this is down to new processes allowing these panels to offer a better colour depth compared with older TN panels.
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The pattern the OP attached contained 3 colours (RGB values of 23,23,23 - 24,24,24 and 25,25,25) that 6-bit TN film panels cannot display natively simultaneously without simulation of one of the above dithering methods.

That would apply for any 3 similar colours within a single step, so the same would be happening for a patter, containg red pixels of, say 240,0,0 - 241,0,0 and 242,0,0. Only the darkest and lightest shades would be displayed natively, the middle shade would (in the case of temporal dithering or FRC) pulse between the lightest and darkest (240 and 242) giving an 'impression' of 241.


This issue (albeit highly exaggerated in this example) would not occur in perhaps the most modern implementations of TN-film panels, or any 8-bit desktop class panel (i.e. IPS or *VA).


By the way, this test will only work if displayed at a 1:1 or 100% zoom size. If any resizing is happening, anti-aliasing will mix the colour pattern to the experiment won't work as intended.
 
I don't see any flickering...I have a 2.33 macbook pro with matte screen...not seeing anything
 
l33r0y said:
The pattern the OP attached contained 3 colours (RGB values of 23,23,23 - 24,24,24 and 25,25,25) that 6-bit TN film panels cannot display natively simultaneously without simulation of one of the above dithering methods.

That would apply for any 3 similar colours within a single step, so the same would be happening for a patter, containg red pixels of, say 240,0,0 - 241,0,0 and 242,0,0. Only the darkest and lightest shades would be displayed natively, the middle shade would (in the case of temporal dithering or FRC) pulse between the lightest and darkest (240 and 242) giving an 'impression' of 241.


This issue (albeit highly exaggerated in this example) would not occur in perhaps the most modern implementations of TN-film panels, or any 8-bit desktop class panel (i.e. IPS or *VA).


By the way, this test will only work if displayed at a 1:1 or 100% zoom size. If any resizing is happening, anti-aliasing will mix the colour pattern to the experiment won't work as intended.
Click to expand...

This certainly makes sense. However, it doesn't explain why I'm able to see (I think) the flicker (although in a much much weaker form) on my Dell screen which uses a true 8-bit S-IPS panel. But is the dithering done in the panel (i.e. GPU sends signal with 'full colors' to the panel) or does the GPU dither the image? I mean, would it be possible that the GPU was sending the dithered signal also to the external monitor, or is this completely impossible?
 
I have my non SR macbook Pro set up with a 20" LG TN 8-bit panel, as my external monitor, and I do not see any flickering at all. Even if I zoom in and out fast, open it up in Safari or Preview no flickering occurs.

Although when I do zoom in all the way in preview all I see is just black, although not pure black but its just black, when I zoom in and out from safari I do see lines everywhere...
 
On my 1 ghz AlBook it just looks black. Only when I zoom in all the way using OS X's screen zoom do I even see the alternating dark grey and darker grey pattern.
 
no flickering on my samsung led. Downloaded full image and cheked it in preview no flicr at all.
 
Did anyone ever get this flicker issue fixed ?

I just got a MBP 2.2GHz glossy LG screen week 41 build. and it flickers on dark grey screens. Is there any fix or do I have to take this one back too. This is my 4th MBP all others had yellowing, freezing, warped casing.

I tryed reseting the PRAM but that didnt help.
 
Apple Store

Wow, I can't stand the flicker. Is there a solution to this annoyance?

I ran into the problem when extending a dark gradient on a website.

I went to the apple store to check if it was a isolated issue on my MBP and it was not. The flicked from the example appeared on all 15in MBPs in the store.

Please Help, before I call everyone one at LG and APPLE and freak out!!!!
 
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