Congratulations, einstein! You found a 12% non-uniformity "problem."
(31 + 51 + 66) / (27 + 46 + 59) = 1.12
I only claimed: "less than 20%"
...thanks for confirming my measurements,
LK
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24" owners with a good screen, please post a pic!
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(31 + 51 + 66) / (27 + 46 + 59) = 1.12
I only claimed: "less than 20%"
...thanks for confirming my measurements,
LK
Did you try searching google images for bad alum iMac screens yet? Any comments on all of the pics showing up now with good iMac alum screens?
I agree that there is no keyboard cable into the Imac... but I do think the display is realtime based on the iChat display... The narrator cannot take the time to look down at the keyboard, nor be expected to do precise mousing, so there is probably an assistant with a wireless keyboard and mouse doing the work.
Uh, why limit the source to "google images" -- especially when a quick search of that site (with domain name filtering) returns NONE of the many gradient-related photos posted in this forum, in discussions.apple.com, or any other Mac-related site?
...try these for starters,
LK
http://discussions.apple.com/message.jspa?messageID=5166261#5166261
https://forums.macrumors.com/posts/4144982/
https://forums.macrumors.com/posts/4145730/
https://forums.macrumors.com/posts/4147167/
https://forums.macrumors.com/posts/4150341/
https://forums.macrumors.com/posts/4159996/
https://forums.macrumors.com/posts/4165464/
https://forums.macrumors.com/posts/4184846/
https://forums.macrumors.com/posts/4249652/
https://forums.macrumors.com/posts/4251236/
https://forums.macrumors.com/posts/4251452/
Well, you've proven my point nicely. All the problems you linked to are from these forums, and there are very few problems in a general search of the web, like google. Could it just be that the forums are biased to the problems, because people tend to come here with problems, and google is biased to no problems, because people showing off their new iMacs don't tend to have problems?
Why so obsessed?
Leon -
Have you returned your aluminum iMac yet? If you have, why are you continuing to be so obsessed with this screen gradient? Anyone that is looking to buy a new iMac will surely see one of the many posts you have on this topic. For those that actually want to pull out the light meter and measure their screens, they will get the real results and appreciate your information and knowledge.
I am just curious to see why you keep posting on this topic over and over? What are you trying to do?
I for one have no intention of using a light meter on my iMac and I bet most people won't! Yes, I spent over $2,000 for this machine and if there is a small screen gradient issue, I am still happy with my overall experience. If the problem was so bad that I actually noticed this problem, I would go back to apple and get a refund.
Your smart a** replies and attempts at making everyone else look stupid for even considering buying an aluminum iMac are really pointless! Please upgrade to the white iMac as you put it and leave it already! Be glad you don't have the aluminum iMac then!
I LOVE MY iMAC!!!! (For all those that are scared off by light meter readings)
Leon -
Have you returned your aluminum iMac yet? If you have, why are you continuing to be so obsessed with this screen gradient? Anyone that is looking to buy a new iMac will surely see one of the many posts you have on this topic. For those that actually want to pull out the light meter and measure their screens, they will get the real results and appreciate your information and knowledge.
I am just curious to see why you keep posting on this topic over and over? What are you trying to do?
I for one have no intention of using a light meter on my iMac and I bet most people won't! Yes, I spent over $2,000 for this machine and if there is a small screen gradient issue, I am still happy with my overall experience. If the problem was so bad that I actually noticed this problem, I would go back to apple and get a refund.
Your smart a** replies and attempts at making everyone else look stupid for even considering buying an aluminum iMac are really pointless! Please upgrade to the white iMac as you put it and leave it already! Be glad you don't have the aluminum iMac then!
I LOVE MY iMAC!!!! (For all those that are scared off by light meter readings)
Wirelessly posted (Mozilla/5.0 (iPhone; U; CPU like Mac OS X; en) AppleWebKit/420.1 (KHTML, like Gecko) Version/3.0 Mobile/3A109a Safari/419.3)
Sounds like this "Leon" character needs to get a real job so he can afford an actual professional, calibrated display and stop complaining about consumer hardware. I have an iMac 24, and its display is perfectly fine, no dead pixels, and much better off axis than any of my other Macs. There is no such thing as a "perfect" display. Period.
Sounds like this "Leon" character needs to get a real job so he can afford an actual professional, calibrated display and stop complaining about consumer hardware. I have an iMac 24, and its display is perfectly fine, no dead pixels, and much better off axis than any of my other Macs. There is no such thing as a "perfect" display. Period.
Leon -
Have you returned your aluminum iMac yet? If you have, why are you continuing to be so obsessed with this screen gradient? Anyone that is looking to buy a new iMac will surely see one of the many posts you have on this topic. For those that actually want to pull out the light meter and measure their screens, they will get the real results and appreciate your information and knowledge.
I am just curious to see why you keep posting on this topic over and over? What are you trying to do?
I for one have no intention of using a light meter on my iMac and I bet most people won't! Yes, I spent over $2,000 for this machine and if there is a small screen gradient issue, I am still happy with my overall experience. If the problem was so bad that I actually noticed this problem, I would go back to apple and get a refund.
Your smart a** replies and attempts at making everyone else look stupid for even considering buying an aluminum iMac are really pointless! Please upgrade to the white iMac as you put it and leave it already! Be glad you don't have the aluminum iMac then!
I LOVE MY iMAC!!!! (For all those that are scared off by light meter readings)
Amen! My new iMac has the "problem" and is the most beautiful screen I have ever owned. I couldn't even see it with a solid grey screen until I took a picture of it which exaggerates the "problem".
Like Leon, I also took delivery of a number of machines that had less than perfect screens. The second was much worse than the first, so much so that my 6 year old nephew commented on it! (and for some unusual reason I got angry, really angry with apple)
Anyhow, those machines are history, I've ordered a third and if it's bad, its going back again (I guess three attempts is enough) .
Problem is, I'm looking for the problems now so I expect to be my own worst enemy.
But guess what, in between all the ranting (some of my own included) I've learnt a thing or two about displays and thats a good thing.
I've also learnt I can wait a while longer than I thought I could and that my 2004 iMac G5 also has a little more life in it than I gave it credit for.
Kuska
I highly doubt that. Are you saying it was CGIed in post? Wow talk about spending a fortune. I don't see why they would blow the budget for that when they could have just moved the camera.
My feeling is that it is real.
The image on the screen was put there afterwards, yes. The whole computer wasn't rendered. I would think that he actually used the computer in the movie but that they captured the whole thing and put it back onto the screen afterwards. That way they can make it appear perfectly uniform and without any glare. (they did this in the iPhone movies as well)
It's really not anything advanced and it doesn't cost much. It's common practice in advertisements that contain screens. In fact I would say that practically every computer/screen advertisement is either done this way or completely computer rendered.
Perhaps you'd also like to know that most product photos from larger companies these days are actually computer rendered. It's cheaper and more practical to do it that way. Product photographers is a dying breed.
I know that I heard Apple was rendering all the product shots on the website, but in this case it seems strange that the time keeps changing on the screen. I guess it could suggest either possibility but to me it suggests that the time changes are due to editing a long day of shooting. If the screen was replaced it would seem to me that the timeline would be more seamless.
hey,
i am a future switcher (am i in the right thread?), and i have been waiting for the leopard release to buy an Imac with the new OS pre-installed. however I was taken a little bit aback after reading all the posts concerning the freezing issue.
did this happen to the vast majority of people or just a few unlucky ones? shall i wait until this is finally fixed or shall i buy it right after october 26th with my fingers crossed hoping that if i ever encounter these sort of problems a future update shoudl fix it or in worst case scenario, i get my machine replaced for a new one of repared?
what do you think?
thanks in advance for your help!
Wow, I am 100% in the same exact situation. Was waiting for Leopard etc. etc....
Now I'm getting cold feet, and thinking I should wait for the 'hardware revision'.... assuming there will be one.... sometime soon.
The type of rendering you are talking about is not the same as would be needed for this off angle shot, and it is very expensive. You are talking about the master shot and not the inserts, right? And let's say it was, you would most likely not be able to tell. What makes you so sure? Do you see visible artifacts?
EDIT: After looking at the HD version of the spot I now see that the stationary shot is used on the master angle. That would be very easy to do in post. I don't see the need, though, as it could be photographed live and not be a problem either.
Dirty is a very good description of it. The thing is that it isn't only darker but yellow/brownish which makes it look.. dirty.
I'll be the first to admit that I'm also no Einstein, but given that sample set you cannot just say "the mean difference is 12%". If you calculate the variance between the measurements (ie: do a student's T-test on that data), you will find that the two means are NOT statistically different.
In other words, (31 + 51 + 66) / (27 + 46 + 59) = no statistically significant difference.
If you can provide numbers with less variability (variance?) on each side, and increase the number of measurements, you may be able to make a significant difference. Until then, you've got nada (that's Spanish English, btw).
For now I'll just stick with my subjective impression that the iMac screens I've seen look Really Good!!
All the best.
WHAT variance? There was ONE measurement of ONE location on each side of the screen. Each datum consists of three independent dimensions: red, green, and blue. The total luminance at each location was approximated by summing three orthogonal values -- NOT by averaging three observations of the same property.
Furthermore, repeated "observations" of any given point on a digitized image will yield EXACTLY the same result every time. There is no possibility of "scatter," because the bits in the image file are time-invariant. What's the standard deviation of your social security number?
And what's your formula for calculating the "variance" of ONE data point?
...innumeracy RULZ!
LK
Initially I'd wondered if the condensation experienced with both machines on initial start up had some way discoloured either the glass or the actual screen itself as the water evaporated, but have no idea if simple condensation would have this type of effect ?
Kuska
After reading all this, not only do you lint pick the iMacs, (if that's so important as compared to the world's real problems), you lint-pick each other's grammar!! I think this thread says more about you than it does the iMac's screen.
If you don't like the screen go buy a windows computer!!!!!
If you don't like the screen go buy a windows computer!!!!!
Oh, well in that case you have NO point whatsoever. You need to collect multiple measurements because you have a high potential for sampling and measurement error, which is not necessarily the same thing as the precision (defined as reproducibility, NOT accuracy) of your measurement. When you've read something about statistics, I'd be happy to have a real discussion.
In the meantime, you sound like your arse is sore about something. Try not to be such an ****** to the community, ok? I'm interested in the topic of a potential screen defect, and you want to toss around insults with the idea that I'm somehow numerically illiterate?? Take it down a notch, I'm not here to be insulted.
Clearly the ravings of an algebraic maniac.
Here, try this little experiment in applied statistics:
1) Count your fingers (both hands, if you can manage it).
2) Carefully record the results in your laboratory notebook.
3) OOPS! Insufficient sample size.
4) Enlist ten thousand or so neutral observers to repeat the measurement.
5) Carefully record their observations in your laboratory notebook.
6) Calculate the mean, median, standard deviation and skew of the sample distribution.
7) Calculate the MoE of your final result at, say, the 95% confidence level. Feel free to use the handy-dandy MoE calculator at http://americanresearchgroup.com/moe.html.
(Hint: Enter Population_Size = 1, Sample_Size = 10001)
8) Report your approximate number of fingers (+/- MoE).
...uh, 4 or 5 significant digits of precision should be sufficient,
LK
"I would advise you Sir, to study algebra, if you are not already an
adept in it: your head would be less muddy, and you will leave off
tormenting your neighbors about paper and packthread ..."
- Samuel Johnson
Are you seriously arguing that a single point measurement is going somehow accurately assess the monitor? And why exactly to you think that a repeat measurement will give the exact same result?? Oh wait a sec... you're not so stupid that you're measuring the screen with the DigitalColor Meter utility, ARE YOU?? Haha! Nice Experimental Design GENIUS! Yeah, that will tell you exactly what the computer has mapped to that area of the screen, but it will not assess he actual output of the screen. Get a monitor calibrating device, and do repeat measurements.
I think I'm done with this topic, and I'm certainly done with you, LK. You come off like an under-educated, snotty little twerp. And FWIW, the correct statistical test is a 2-tailed Student's T-test (margin of error won't get you where you need to be). You bore me.
You're projecting, Bubba. Please refresh my memory on WHO jumped into the fray babbling utter nonsense about "student's T-tests", "statistically significant differences" and "variance" -- of a SINGLE data point, no less.
When you find yourself in a hole of your own making -- STOP DIGGING!
Yet another lame straw man. The weasle-worded phrase "assess a monitor" is nothing but a transparently dishonest attempt to muddy the waters and divert attention from your astoundingly idiotic "statistical" pronouncements.
The subject was not "assessment" (whatever that might mean) -- it was a discussion of LUMINANCE UNIFORMITY, which (unfortunately for you), is an easily-understood, precisely-defined, and unambiguously quantifiable property of LCD displays.
Widely-accepted international standards define and specify luminance uniformity as a simple ratio of maximum to minimum brightness. No statistics involved; just divide the brightest by the darkest. Any errors in locating the absolute brightest/darkest areas of the screen simply produce a slightly optimistic result. No big deal. No one cares if it's off by a few percent.
As I already explained, there is nothing to repeat -- and no reason to repeat it. The data-set under discussion (a more-than-sufficient 10 million+ discreet RGB brightness measurements) was acquired by Mr. Sushi's superb Canon IXY DIGITAL 700 camera -- in a matter of 20 milliseconds -- and promptly recorded on his SD flash card. Measurement complete! Everything after the shutter-click is data analysis -- NOT measurement.
Are you seriously suggesting that replicate high-quality digital photographs of the same display -- taken back-to-back, on the same day -- would yield substantially different results? Remember, Bubba, we're NOT talkin' about ppm precision hair-splitting; we're talkin' about macroscopic brightness differences -- on the order of tens (or hundreds!) of percents.
Please tune-in Sesame Street for a refresher course on "big" and "little."
What a maroon! I wouldn't have thought it possible that anyone capable of operating a keyboard could be so invincibly dense. The "actual output" of the iMac screen was ALREADY measured once -- by Mr. Sushi's camera. There is nothing more to measure. The data is now written in silicon; no matter how many times you "sample" it, it remains unchanged.
Anyone who follows your sage technical advice will be measuring the "actual output" of Mr. Sushi's display -- MULTIPLIED BY -- the "actual output" of the second display. ...but why stop at only two?
The ideal method of analyzing the 10 million+ RGB measurements acquired by Mr. Sushi's camera would be to programatically extract and process the binary JPG data -- directly from the camera's SD flash card.
The next best approach is an interactive graphical examination/analysis of the JPG's data bits -- exactly as they are "mapped" by the computer into an area of video memory. I freely admit that DigitalColorMeter.app has its limitations. OTOH, it's universally available, and good enough for detecting gross non-uniformities and distinguishing between "big" and "little."
Oooh! Now we have a TWO tailed test ... for the same ol' ONE data point!
...stupidity has no asymptote!
LK
No, this seems to be related to the backlighting. Because with those screen where the backlighting is fading from left to right the yellowish area is at the right side and not exclusively in the middle.
One interesting thing is that it varies in visibility over time as well. Sometimes it's barely visible and sometimes it's very obvious and quite annoying.
As has already been said, you're boring us. Why don't you just NOT get an iMac and be done with it? Or better still: get a life, instead of spending countless hours with your multi-quote posts which are repetitive and lacking in substance - I mean, don't you have anything better to do with your time? It's laughable (and sad and pathetic) that you don't.
posted from a 24" iMac with a good screen