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Panel Question imac 20'' (2009)

rjp said:
In addition to the brightness difference, what you are demonstrating here is the difference between matte and glossy.
Click to expand...

Well the brightness level is set to the same, in addition a glossy screen when viewed from the side should show a "mirror effect' if it is a 6-bit panel, as does this dell panel.

when viewed straight on the dell is as bright as my imac.

A easy way to settle this would be to have someone with a LG panel imac to submit a pic similar to mine. That would solve this easily.

In Addition. the facts as we know them are:

There are two manufactures of panels for the 2009 imacs. As in previous years.

The panels in question are the LM201WE3 which is a LG and a AUO M201EW02 VF. Here are the specs for each:

http://lcdtech.no-ip.info/en/data/monitor.lcd.panels.htm?pan=LM201WE3

The M201EW02 VF is not listed here so we can surmise that of all the 2009 panels in production which there are three. A V8, a VO and a VC. of all of the ones listed the VC matches the AUO panel in the ifixit article tear down. With it having "four backlights'.

"As we mentioned earlier, this iMac still uses an LCD with a CCFL backlight. This particular display features four backlights, each of which require their own high-voltage AC power."

http://www.ifixit.com/Guide/First-Look/iMac-20-Inch/658/2

The only panel in production for 2009 for AUO that has four backlights is the 'VC' version. Also the "VC' also has a contrast ratio of 1000:1 same as the LM201WE3. I highly doubt that Apple would use panels with two different contrast ratio's. Here are the panels is question:

http://lcdtech.no-ip.info/en/data/m...br=&cr=&va=&rt=&int=&dim=&pwr=&blt=&wei=&coa=

Now what we are essentially comparing here is a panel from two manufactures. One a 6-bit panel and one a 8-bit panel.

A 8 bit panel would have a higher viewing angle and show colors more accurately. This is a big discrepancy in the 2009's panels. As well as previous years. Some using 8-bit and some using 6-bit with FRC. Here is a good article explaining the issue.

http://www.tftcentral.co.uk/articles/content/6bit_8bit.htm#8bit TN

So what you're basically saying that the 2007 panel that you have is no different that a 2009 regardless of who makes that panel. If so you're ignoring the facts. If that is what you want to believe, thats your prerogative. You would be ignoring the facts, no question.
 
iamthedudeman said:
Well the brightness level is set to the same, in addition a glossy screen when viewed from the side should show a "mirror effect' if it is a 6-bit panel, as does this dell panel.

when viewed straight on the dell is as bright as my imac.

A easy way to settle this would be to have someone with a LG panel imac to submit a pic similar to mine. That would solve this easily.

In Addition. the facts as we know them are:

There are two manufactures of panels for the 2009 imacs. As in previous years.

The panels in question are the LM201WE3 which is a LG and a AUO M201EW02 VF. Here are the specs for each:

http://lcdtech.no-ip.info/en/data/monitor.lcd.panels.htm?pan=LM201WE3

The M201EW02 VF is not listed here so we can surmise that of all the 2009 panels in production which there are three. A V8, a VO and a VC. of all of the ones listed the VC matches the AUO panel in the ifixit article tear down. With it having "four backlights'.

"As we mentioned earlier, this iMac still uses an LCD with a CCFL backlight. This particular display features four backlights, each of which require their own high-voltage AC power."

http://www.ifixit.com/Guide/First-Look/iMac-20-Inch/658/2

The only panel in production for 2009 for AUO that has four backlights is the 'VC' version. Also the "VC' also has a contrast ratio of 1000:1 same as the LM201WE3. I highly doubt that Apple would use panels with two different contrast ratio's. Here are the panels is question:

http://lcdtech.no-ip.info/en/data/m...br=&cr=&va=&rt=&int=&dim=&pwr=&blt=&wei=&coa=

Now what we are essentially comparing here is a panel from two manufactures. One a 6-bit panel and one a 8-bit panel.

A 8 bit panel would have a higher viewing angle and show colors more accurately. This is a big discrepancy in the 2009's panels. As well as previous years. Some using 8-bit and some using 6-bit with FRC. Here is a good article explaining the issue.

http://www.tftcentral.co.uk/articles/content/6bit_8bit.htm#8bit TN

So what you're basically saying that the 2007 panel that you have is no different that a 2009 regardless of who makes that panel. If so you're ignoring the facts. If that is what you want to believe, thats your prerogative. You would be ignoring the facts, no question.
Click to expand...

I'm not ignoring any facts. I hear all your facts any I'm weighing them as carefully as I can. So far, you seem to be the only one with one of these special 20" panels. Maybe as time goes on others will pos their panel numbers and we'll see how widespead this is.

But so far, I don't see anything about your display that looks any different than mine. If it is the panel you suspect and really is 8 bits, that's great. Good for you. You are lucky. That panel also has a 92% gamut! Do you understand just how significant that is? The other panels in the 20" imacs have around 76% color gamut. If I were Apple, and I offered a monitor with an incredible 92% gamut, you can be darn sure I'd advertise this fact!

Maybe they just got a hold of a handful of these higher quality screens and you lucked out in getting one. Or maybe you're making the whole thing up? So far your's looks no different than any other 20" imac screen I've seen, and you seem to be the only person possessing the AUO version if I'm not mistaken. (Well, you and Mr ifixit) Have there been any others?
 
rjp said:
So far, you seem to be the only one with one of these special 20" panels. Maybe as time goes on others will pos their panel numbers and we'll see how widespead this is.

Or maybe you're making the whole thing up? So far your's looks no different than any other 20" imac screen I've seen, and you seem to be the only person possessing the AUO version if I'm not mistaken. (Well, you and Mr ifixit) Have there been any others?
Click to expand...

Go to page 6 of this thread, post #137: tms568, the threadstarter stated he has this AU panel.
 
rjp said:
But so far, I don't see anything about your display that looks any different than mine. If it is the panel you suspect and really is 8 bits, that's great. Good for you. You are lucky. That panel also has a 92% gamut! Do you understand just how significant that is? The other panels in the 20" imacs have around 76% color gamut. If I were Apple, and I offered a monitor with an incredible 92% gamut, you can be darn sure I'd advertise this fact!
Click to expand...

That is a logical supposition, unless e.g. (just conjecture):

a) apple had only limited inventory of this panel which could not meet customer demand after the iMac update
b) there were quality issues with (batches of) this panel causing them to initially revert to using a different (previous) panel
c) apple felt there was no perceptible difference between the two panels
d) something else
 
Canadian Bacon said:
Go to page 6 of this thread, post #137: tms568, the threadstarter stated he has this AU panel.
Click to expand...

Thank you for the correction. So yes, there are at least two people reporting having this panel. It would be useful to get a larger sample if more people would try the terminal method and report.

So far we have no conclusive information as to whether this is a 6 or 8 bit panel since the model is not listed on AUO. I think there are screen test available that can determine this using gradients. The 6 bit version should have more banding. I will try to locate one.

Yes, quite possible Apple put these in just a few units and so did not mention it.
 
My panel

Hi everyone,
I'm a first time poster and have been following this thread for several weeks. I have a two-week old 20' alu imac (2009) and think I may be able to clear up at least some of the confusion. Here are the specs of my imac:

1) Panel number is LM201WE3 (like most all posters at this point; different from dudeman)
2) Model number is MB417LL/A (same as dudeman)
3) I've done the color swatches test several times now, and the panel looks exactly the same as dudeman's. No color shift from the sides, but very obvious from the bottom (and top).

Based on dudeman's images, I don't have any reason to believe his panel is any different in quality from my own (since mine looks EXACTLY the same).

I've been following the thread because I've been debating seriously whether or not I could live with the 20 inch. The panel is BEAUTIFUL in almost every way, and I don't do graphic design, movie editing, etc, so am not engaged in any activity that requires extreme accuracy in color representation. However, the shift is obvious to me, even looking straight on at the computer (I can see that "whites" are different from top to bottom). I've been trying to get used to it for the last couple of weeks and have pretty much decided to keep the computer. It would have cost me $350 more (I got an additional discount on the 20inch) for the 24 inch, so I think I've decided I'd rather roll that money into something else (I'll buy more RAM, then think about getting either an ipod touch or a great pair of speakers...or even better, maybe I'll just get a flat-panel TV and save the TV viewing for a real dedicated item!).

It's been a tough decision, but at the end of the day, the 20in is a great computer and fits my needs. However, it does have color shift, and the theory about different model #s corresponding to different panel quality doesn't hold up. Additionally, my panel (with a different part # and manufacturer) behaves exactly as dudeman's, leading me to believe there's no difference in the quality of the two panel types.

Hope this helps. Again, the 20inch is a great computer. It pains me somewhat not to have the 24inch, but at the end of the day, it's not a necessity for my life and I can envision other uses for that $$.
 
Pics only proved that the this new panel model # still has the top to bottom contrast shift. Pretty much means it is a 6-bit panel.
 
The 20" is beautiful!

mysterygirl said:
Hi everyone,
I'm a first time poster and have been following this thread for several weeks. I have a two-week old 20' alu imac (2009) and think I may be able to clear up at least some of the confusion. Here are the specs of my imac:

1) Panel number is LM201WE3 (like most all posters at this point; different from dudeman)
2) Model number is MB417LL/A (same as dudeman)
3) I've done the color swatches test several times now, and the panel looks exactly the same as dudeman's. No color shift from the sides, but very obvious from the bottom (and top).

Based on dudeman's images, I don't have any reason to believe his panel is any different in quality from my own (since mine looks EXACTLY the same).

I've been following the thread because I've been debating seriously whether or not I could live with the 20 inch. The panel is BEAUTIFUL in almost every way, and I don't do graphic design, movie editing, etc, so am not engaged in any activity that requires extreme accuracy in color representation. However, the shift is obvious to me, even looking straight on at the computer (I can see that "whites" are different from top to bottom). I've been trying to get used to it for the last couple of weeks and have pretty much decided to keep the computer. It would have cost me $350 more (I got an additional discount on the 20inch) for the 24 inch, so I think I've decided I'd rather roll that money into something else (I'll buy more RAM, then think about getting either an ipod touch or a great pair of speakers...or even better, maybe I'll just get a flat-panel TV and save the TV viewing for a real dedicated item!).

It's been a tough decision, but at the end of the day, the 20in is a great computer and fits my needs. However, it does have color shift, and the theory about different model #s corresponding to different panel quality doesn't hold up. Additionally, my panel (with a different part # and manufacturer) behaves exactly as dudeman's, leading me to believe there's no difference in the quality of the two panel types.

Hope this helps. Again, the 20inch is a great computer. It pains me somewhat not to have the 24inch, but at the end of the day, it's not a necessity for my life and I can envision other uses for that $$.
Click to expand...

Thanks for chiming it. Appreciate your input very much.

I also feel the 20" imac is a wonderful display. Like you, I have been torn between the 20 and 24. Yes, the 24 is obviously better, but this 20 is absolutely beautiful too! We forget this in these threads since the people most motivated to post are typically the ones who are unhappy. But hey, let me give credit where it's due, and it's due here.

I mean, this has got to be the most beautiful display I've ever seen! (At least when I'm looking directly at it).

Still can't decide if I want to pay 200 more for the 24" (refurbs here).

I'm actually afraid it might seem too massive.
 
trip1ex said:
Pics only proved that the this new panel model # still has the top to bottom contrast shift. Pretty much means it is a 6-bit panel.
Click to expand...

You don't pay attention much do you? AUO 20.1 panels are all 8 bit. I have proven as much with the links I posted. If you have some hard info proving otherwise please post it.
 
rjp said:
Thank you for the correction. So yes, there are at least two people reporting having this panel. It would be useful to get a larger sample if more people would try the terminal method and report.

So far we have no conclusive information as to whether this is a 6 or 8 bit panel since the model is not listed on AUO. I think there are screen test available that can determine this using gradients. The 6 bit version should have more banding. I will try to locate one.

Yes, quite possible Apple put these in just a few units and so did not mention it.
Click to expand...

There are thousands of people with this panel. Believe it or not not everyone who owns a mac is on this site.

"So far we have no conclusive information as to whether this is a 6 or 8 bit panel since the model is not listed on AUO."

Thats just a weak excuse. C'mon RJP. The model listed on ifixit.com and the teardown had four back lights. There is only one model of AUO 20.1 panel with four back lights and that is the "C'. Furthermore there is not a panel in AUO current production of 20.1 panels with a 6-bit panel. please find me one.
 
Just checked my panel # using Terminal;
I have M201EW02 VF

The above is the number for my Alu iMac 20" 2009.
I have two other 20" Alu iMacs, my kid's 2008 (spring)
And the wife's 20" Alu iMac 2007 (summer)

I will check the other two numbers after I get through work.
Cheers.
 
iamthedudeman said:
You don't pay attention much do you? AUO 20.1 panels are all 8 bit. I have proven as much with the links I posted. If you have some hard info proving otherwise please post it.
Click to expand...

My hard proof is in those pictures you posted. They show that the panel still has the contrast shift from top to bottom which was the biggest complaint about the 20" from what I remember.

So it is kind of a moot point now.
 
rjp said:
Are you sure about that? I thought it was the TN technology that caused the contrast shift, not the number of bits per color.
Click to expand...

Anyone who doesn't care about the contrast shift will hardly care if the panel is 8-bit vs 6-bit. OR so it seems to me.
 
For what it is worth, based on what I've read TN panels are only 6-bit. And only achieve more colors through various techniques like dithering or FRC.

Manufacturers are listing more TN panels as 8-bit now or achieving 16.7 million colors, but again from what I read it seems like this is due to advanced techniques along the lines of dithering and FRC. At least I haven't seen any sources that reassure there are actual 8-bit TN panels.
 
Just got my new 2009 20" iMac. panel # M201EW02 VF

and

~: user trip1eX has been disconnected
 
Technical difficulty.

New panel is sweet. Just as good as 24". Obviously 8-bit. Contrast shift is minimal. I guess I won the panel lottery. Just as Dudeman said. I guess I was owned.


Now I have a few other problems though.

First, my dvd drive burps every 5-10 minutes with no disc in it. The sound is basically a second or two of what you hear when you put in a disc. It is like the drive senses a disc being inserted, starts up for a second or so and then quickly stops. I've heard this 10x or so since I got this thing yesterday. It's a fake starup noise. :)

Also fans seem a bit faster and louder. Computer is far from hot on the back. Matter of fact super cool compared to my previous iMacs. Maybe these fan speeds are why.

1200 rpm cpu
1600 rpm hard drive
1350 rpm optical.

The 24" had 1200 cpu fan going all the time. But optical and hard drive were at least 400-500rpms slower.
 
trip1ex said:
Technical difficulty.

New panel is sweet. Just as good as 24". Obviously 8-bit. Contrast shift is minimal. I guess I won the panel lottery. Just as Dudeman said. I guess I was owned.


Now I have a few other problems though.

First, my dvd drive burps every 5-10 minutes with no disc in it. The sound is basically a second or two of what you hear when you put in a disc. It is like the drive senses a disc being inserted, starts up for a second or so and then quickly stops. I've heard this 10x or so since I got this thing yesterday. It's a fake starup noise. :)

Also fans seem a bit faster and louder. Computer is far from hot on the back. Matter of fact super cool compared to my previous iMacs. Maybe these fan speeds are why.

1200 rpm cpu
1600 rpm hard drive
1350 rpm optical.

The 24" had 1200 cpu fan going all the time. But optical and hard drive were at least 400-500rpms slower.
Click to expand...


Huh? You had just written that you were convinced the contrast shift demonstrated in dudeman's pics indicated it was a 6 bit panel. How can you now say it is as good as the 24"?

trip1ex wrote:
">> My hard proof is in those pictures you posted. They show that the panel still has the contrast shift from top to bottom which was the biggest complaint about the 20" from what I remember..
>> Pics only proved that the this new panel model # still has the top to bottom contrast shift. Pretty much means it is a 6-bit panel. "

I have an application that I downloaded last year called LCDTest 1.0 that presents nice color gradient patterns on the mac screen. Using this I can see the difference between 6 bit and 8 bit colors on my imacs. The 8 bit is much smoother, whereas the 6 bit has more distinct banding. The 8 bit still has bands, but they are much finer and harder to see.

I wish I could give you a link to the app but all the links I find online today are down. Perhaps I could send the application itself if you'd like to try it.

Here is the link. Maybe you can get it to work. You want the gradient test.
http://azlan.anilezfa.com/mac-lcd-test-for-find-dead-pixels

This is the only way I know of to distinguish 6-bit from 8-bit panels.
 
I got owned I guess. He was right.

Wife likes the 20" size better too. Go figure. There is something to be said about everything concentrated right in front of you.

My iMac does this weird sound though every 5-10 minutes still. It just did it as I was typing. It sounds like the optical drive is faking a start up.
 
trip1ex said:
I got owned I guess. He was right.

Wife likes the 20" size better too. Go figure. There is something to be said about everything concentrated right in front of you.

My iMac does this weird sound though every 5-10 minutes still. It just did it as I was typing. It sounds like the optical drive is faking a start up.
Click to expand...

Congrats on winning the panel lottery. Get it repaired rather than replaced as you won't want to play the lottery again.
 
rjp said:
Huh? You had just written that you were convinced the contrast shift demonstrated in dudeman's pics indicated it was a 6 bit panel. How can you now say it is as good as the 24"?

trip1ex wrote:
">> My hard proof is in those pictures you posted. They show that the panel still has the contrast shift from top to bottom which was the biggest complaint about the 20" from what I remember..
>> Pics only proved that the this new panel model # still has the top to bottom contrast shift. Pretty much means it is a 6-bit panel. "

I have an application that I downloaded last year called LCDTest 1.0 that presents nice color gradient patterns on the mac screen. Using this I can see the difference between 6 bit and 8 bit colors on my imacs. The 8 bit is much smoother, whereas the 6 bit has more distinct banding. The 8 bit still has bands, but they are much finer and harder to see.

I wish I could give you a link to the app but all the links I find online today are down. Perhaps I could send the application itself if you'd like to try it.

Here is the link. Maybe you can get it to work. You want the gradient test.
http://azlan.anilezfa.com/mac-lcd-test-for-find-dead-pixels

This is the only way I know of to distinguish 6-bit from 8-bit panels.
Click to expand...

I just provided "proof' that this a 8-bit panel by listing every AUO 20.1 2009 panel in production on this thread and none of them list being a 6bit panel. Re-read my posts and you will see what I mean. If this thread was law and order, you would be in jail. Lol.

Further more ifixit tore down a 20 2009 imac with my panel and it had four back lights, same as the 2009 i listed.

Is it as good as a 24' probably not. Does it look as good to me. Yes it does. Does that mean it is. No

Glad to see that I am not crazy, Tri. What ever you do don't hand in your mac if there is a problem, get it fixed.
 
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