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post #1 of 141 Old 05-13-2013, 01:33 PM - Thread Starter
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There's voltage adjustment for black levels but my blacks are quite black.Is there any voltage adjustments that improve white levels/white clipping,tone down whites? I doubt I would try it.Id guess it's the abl that Causes some of it.....turning contrast down helps some,but if you lower it too much then the brights whites on some screens will wash out.

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post #2 of 141 Old 05-14-2013, 12:24 PM
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No there is NOT a voltage adjustment for black level in digital video displays. If you think that is true, you are not understanding some of the fundamentals of calibration. In the old days of analog video with CRTs, there was a voltage level that controlled how black the display was (among other things) but you typically would adjust that by eye (looking at a PLUGE pattern on the display), not by setting it to some specific voltage.

In a digital video display (you did not even include enough of the model number for any of us to determine whether you are talking about a plasma TV or LCD TV, but both work more or less the same way), you display a PLUGE pattern and adjust the Brightness control to get the black level set correctly. No video displays made today have "perfect" black when displaying black video information. A couple of plasma displays (Gen 2 Pioneer Kuros from several years ago and a few new Panasonic plasma models) come very close to having very very very black blacks, but other plasmas and all LCD displays have a black level that isn't perfectly black. There is nothing you can do about it other than purchase a better TV that offers blacker blacks.

A PLUGE pattern usually contains "below black" plus black plus a third level that is a little above black. You adjust the Brightness control to get the black part of the PLUGE pattern to match the "below black" part of the PLUGE pattern so everything at or below black is as dark as the display can make it.

White level is set by the Contrast control. Once again, in digital video displays, there is no "voltage" you set for white level. You set Contrast to achieve a 100% white level of around 35 fL in a dark room. If you have no meter to perform this measurement, you are just guessing. Using a test pattern with digital values of 200-245 will show you whether the TV clips or not... some digital displays do, some do not, actually, these days, many digital displays do not clip white levels. But whether or not the display clips white levels doesn't necessarily have a lot to do with whether you have 35 fL or a headache-inducing 70 fL (when viewed in a dark room). All you can tell is what setting range you can use before clipping begins. If you look at the Contrast control and it has a range of 0-100 and you always see levels 200-254 no matter what Contrast setting you use, that TV just does not ever clip. But you still no nothing about how bright the TV is if you don't have a meter. Your only "tell tale" about whether Contrast is set too high is eyestrain. If you watch a movie for 2 hours and you detect a feeling of eyestrain, chances are the Contrast control is set too high. If you can watch a whole movie in a dark room without feeling like you have eyestrain, your Contrast control is set either correctly or too dark. The only way to know if it is set too dark is to raise the Contrast control and watch another 2 hour movie and see if you got the feeling of eyestrain... if you did, Contrast is now too high and it should be lowered. Learning the best Contrast setting without a meter can take some time... probably weeks of trying different settings and viewing content for 2-hour stretches to see whether you are comfortable or not.

It really sounds like you need to learn a lot more about calibration before you go looking for adjustments or settings that aren't right in front of you in the User Menu.

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post #3 of 141 Old 05-16-2013, 04:44 AM - Thread Starter
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On mine Anything much above 70 contrast makes the bright patches( which can be small or large patches)quite bright on some screens.Im wondering if it happens more on the lower budget models like I have( Sam 51pne450).I seen a Sam pne6500 next to the Sam pne450 and there was a bit more glare coming off the foreheads on the pne450. Not a lot but I could see it a bit.That may be another issue though.
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post #4 of 141 Old 05-16-2013, 05:28 AM
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Vic

You might want to find an article authored by Kal entitled "calibration for dummies".

It would be a good first step in learning calibration.

I'd give you a link but AVS oftentimes removes links from post.

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post #5 of 141 Old 05-16-2013, 06:13 AM
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Greetings

For learning about setting contrast and brightness, you can watch the tutorial videos here.

If you want to learn a whole lot more, then you could consider the video training series. If your time is not worth too much to you, then you can just keep foraging for information from articles and forums one piece at a time around the web.

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post #6 of 141 Old 05-16-2013, 03:59 PM - Thread Starter
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Thanks folks.I calibrate colors which is difficult and other things by eye because I know some things too look for.it's taken a long time and practice."I have a critical eye and know how too spot some problems on the tv".I've tried using patterns( I probably should try more patterns but after trying the video essentials disc I wasn't that impressed with it), and other peoples ideas but am not always satisfied with results.(example if I set brightness the way some recommend then my tv looks too dark in the darker screens and too bright on the bright screens like it's out of balance or it's a plasma thing.If I set contrast too high the whites are too bright( on some screens)and etc.etc..Biggest thing a meter would help with is the shifting gammas.

If you want too see over bright whites watch a teams white uniforms in baseball(Ny Yankees)or basketball.Its easier too spot if you watch It in black and white.
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post #7 of 141 Old 05-16-2013, 08:05 PM - Thread Starter
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Just watched Yankee game and can confirm that this excellent working CRT TV i have has the overblown whites too(its often caused by stadium lighting,direct sun on a white object)..This CRT handles the grayscale shades better so its less noticable than this plasma,even though this plasma on some screens is very good.This issue is also to do with the inconsistent plasma gamma(Uneven white too grayshades too blackshades transition) which makes this more noticable.

Hey Doug you were right about ycc444 better than rgb.The gamma is better on ycc444,and rgb is more difficult to calibrate,especially without a meter.I thought maybe the ycc was making the shiny reflections off objects elevated ,but lowering contrast I think resolves most or all of this.i know it's source , the way it's filmed relatated as well.

Most of the problems I have/notice are in the transition between brighter shades of gray too the brightest whites( color temp between them too).From the darkest shades to a bit lighter has transition problems too,but can be relieved by upping brightness which also relieves blackcrush, but upping brightness can cause washout in some average picture level screens.Lowering contrast helps overblown whites but causes washout on some whites.It's a juggling act.

Thanks for the link Micheal.i read one article and was an interesting read.Hope there's more
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post #8 of 141 Old 05-17-2013, 10:49 AM
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Originally Posted by Vic12345 View Post

Thanks folks.I calibrate colors which is difficult and other things by eye because I know some things too look for.it's taken a long time and practice."I have a critical eye and know how too spot some problems on the tv".

You cannot trust your eye. Just search the internet for "optical illusions" to see MANY examples of how your eyes will fool you when it comes to color and black&white. For example, your eye will tell you that the blue-est and brightest thing on the screen is "white" even if it is very inaccurate (i.e. not accurately d65 white). So you could have a grayscale ramp pattern displayed (many grayscale steps displayed at the same time) and 90% might look too yellow and 100% might look nice and white... but when you measure those patches with a meter, you find out that 90% is accurate (d65 white) while 100% is much too blue. You cannot stop that from happening even if you KNOW 90% is accurate and 100% is not. It's just the way your eyes work.

Never trust anyone who claims they can calibrate "by eye" because they have a "critical eye". It's just not possible. That's why we use meters... meters are not fooled by optical illusions and the shortcomings of human vision. I have a "critical eye", having 34 years of engineering and technical experience (and training from image science professionals) on professional imaging systems including cinema systems. I see things in images that few others would ever see... but there's no way I would EVER attempt a calibration without a meter, I am very aware of how easily my eyes are fooled.

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post #9 of 141 Old 05-17-2013, 12:34 PM - Thread Starter
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Mentioned it b4 I also compare it to an iPad that is accurate and somewhere between ?6700-7000color temp according to 1 article that tested it..I also did read an article that said one generation of the IPOD(a different machine) had some problems with color accuracy( different machine)..The iPad, another tv and the sun are what I compare it too.That's all I use.

Out of the box warm2 was quite red in the dark shades and blue in the brightest parts.That did not look right too me.Skin tones off too.I thought it's suppose too look a little closer too black and white,and 1 color temp.

I agree about the eyes being inaccurate and illusions often,but my eyes are viewing the screen.Some peoples eyes are very inaccurate,some are not bad, mine are in the middle.It takes me several days or weeks of watching to spot a problem,because I know at least a few things too look for.There is "Nothing" as important as being able to spot a problem.Only a meter may be better able.If you calibrate colors as much as I have you eventually learn how they work.It just took me quite a long time.Way Way too long!!

Cheers
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post #10 of 141 Old 05-18-2013, 12:38 PM
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Color temperature is mostly a worthless concept for determining the accuracy of white. Color Temperature is 98% influenced by red and blue. Human vision is most sensitive to green but the amount of green in the white barely affects color temperature.

We calibrate o a white standard of d65... that takes red, green, and blue into account and represents a single value for white. If you plot a 6500K line on a color space chart you get a curved line indicating all the points within the color space that will measure 6500K... hence, 6500K is NOT something you can use to determine whether your white is accurate of not.

Which brings us back to the inescapable fact that the only way to know if your display is accurate or not is to use an accurate meter to measure it.
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post #11 of 141 Old 05-18-2013, 01:43 PM
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Doug is right smile.gif He know's what he is talking about D65 it's a specific point 313x 329y . 6500K can be a white point that is either too magenta or too green. Your eyes fool you it doesn't matter if your looking a screen that is close to 6500K, if it's not D65 then it will not be accurate to use as a refrence. Use an accurate meter to measure and set your greyscale.
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post #12 of 141 Old 05-18-2013, 01:44 PM - Thread Starter
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Green affects the color of the white a lot.Ive driven myself NUTS trying too get whites right by eye...Looking at suns reflections on white objects does work much better than guessing,but my eyes are more accurate in a pitch black room(where I use an iPad).I think the iPad way may work better because my eyes are not as accurate in the sun.

Because this tv makes the BIG white patches(as well as small ones)really bright it's important to try to get the right color temp on them as they are so Noticable.Also the transition from big bright patch to the next darker shade/s is important too get right on this tv.Gamma 0 works best for that transition on mine I've found.

When doing grayscale I check it by watching tv over multiple days/week too see if I notice anything.The biggest mistake is changing it everyday or too often.cool.gif

It's hard too get the red gain right but important on this tv.Seems best if i do that gain last.Blue gain is easier too get right.One mistake I've made too often is getting a dull looking screen.
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post #13 of 141 Old 05-18-2013, 07:51 PM
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Originally Posted by Vic12345 View Post

Green affects the color of the white a lot.Ive driven myself NUTS trying too get whites right by eye...Looking at suns reflections on white objects does work much better than guessing,but my eyes are more accurate in a pitch black room(where I use an iPad).I think the iPad way may work better because my eyes are not as accurate in the sun.

Because this tv makes the BIG white patches(as well as small ones)really bright it's important to try to get the right color temp on them as they are so Noticable.Also the transition from big bright patch to the next darker shade/s is important too get right on this tv.Gamma 0 works best for that transition on mine I've found.

When doing grayscale I check it by watching tv over multiple days/week too see if I notice anything.The biggest mistake is changing it everyday or too often.cool.gif

It's hard too get the red gain right but important on this tv.Seems best if i do that gain last.Blue gain is easier too get right.One mistake I've made too often is getting a dull looking screen.

you should really read some of the articles on this site



http://www.tlvexp.ca/2013/05/beginners-guide-to-the-articles/

also the new ones in the index section (http://www.tlvexp.ca/)
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post #14 of 141 Old 05-18-2013, 11:42 PM
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Horses ... Water ...
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post #15 of 141 Old 05-19-2013, 03:46 AM - Thread Starter
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...drinking water. Ah!

* I'm referring to big white patches with regular full screen shows

I cannot watch the tv anymore with a 73 contrast setting.Too dull.Tweaked colors and Upped contrast to 85,Lookin much better...did notice if anyone cares that when there is a big bright white patch that the red gain has no effect on the patch past around 26 but green and blue still does.
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post #16 of 141 Old 05-19-2013, 11:50 AM
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Yes, green affects the color of white a lot. But color temperature tells you almost nothing about how green or magenta white is.

The problem here is that you really don't know enough about this stuff to know how "off" your comments are. Glad to see you are reading up on the issues, comprehension will come with time.

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post #17 of 141 Old 05-20-2013, 10:16 AM
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Originally Posted by Doug Blackburn View Post

Yes, green affects the color of white a lot. But color temperature tells you almost nothing about how green or magenta white is.

The problem here is that you really don't know enough about this stuff to know how "off" your comments are. Glad to see you are reading up on the issues, comprehension will come with time.
?

+1, you need a foundation of the basics first Vic. Man, sorry Doug, I keep quoting you instead.
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post #18 of 141 Old 05-20-2013, 10:21 AM
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Ok, Vic, it seems to me that you are disperately trying to find a method to setting up your picture without a meter , looking a source you deem accurate like your Ipad , using your eyes. Start with this, reset your Movie Mode to defautls , do just the basic picture setup, Contrast, Brightness, Color/Tint, Sharpness and turn off any enhancements. If you find Warm 2 too red for your liking then change it to warm 1. Warm 2 is closest on the samsungs to the D65 standard but will probably still be way too red. I wouldn't adjust anything to do with whitebalance. Watch the newly adjusted picture and live with it or your other options are to calibrate it with an accurate meter or hire a pro. Otherwise leave the white balance settings alone. This is my best advice to you smile.gif
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post #19 of 141 Old 05-20-2013, 12:48 PM
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Ok, Vic, it seems to me that you are disperately trying to find a method to setting up your picture without a meter , looking a source you deem accurate like your Ipad , using your eyes. Start with this, reset your Movie Mode to defautls , do just the basic picture setup, Contrast, Brightness, Color/Tint, Sharpness and turn off any enhancements. If you find Warm 2 too red for your liking then change it to warm 1. Warm 2 is closest on the samsungs to the D65 standard but will probably still be way too red. I wouldn't adjust anything to do with whitebalance. Watch the newly adjusted picture and live with it or your other options are to calibrate it with an accurate meter or hire a pro. Otherwise leave the white balance settings alone. This is my best advice to you smile.gif

+1 and if he reads some of the articles from Michael Chen (THX Instructor/Pro Calibrator) I linked to earlier, he'll see why this is the best that can be done without meters/software or hiring a good pro

here are some specific links again...

http://www.tlvexp.ca/2013/03/poor-tv-picture-quality-not-happy/

http://www.tlvexp.ca/2012/01/calibration-who-died-and-made-you-god/

http://www.tlvexp.ca/2013/05/i-know-what-love-is-i-mean-what-good-is/

http://www.tlvexp.ca/2013/04/polly-want-a-cracker/

http://www.tlvexp.ca/2013/01/calibration-boneheads/

http://www.tlvexp.ca/2012/12/the-fruits-of-copying-settings-the-pioneer-lottery/
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post #20 of 141 Old 05-20-2013, 03:03 PM - Thread Starter
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Thanks for replies.Just to confirm the problem I was having was color temperature and "gamma" between the brightest white patches and next darkest shades.
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post #21 of 141 Old 05-20-2013, 03:27 PM
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Thanks for replies.Just to confirm the problem I was having was color temperature and "gamma" between the brightest white patches and next darkest shades.

Both things that can't accurately be done without a meter.
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post #22 of 141 Old 05-20-2013, 05:31 PM - Thread Starter
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Tv only has 2 point controls.A meter does not prevent the bright white patches from going super bright.I would think every plasma is a little bit different in how it determines brightness and gamma of the brightest patches...The better I've got it looking the more I've been able too live with this problem.Its a problem,but not as much as a tv that's too dim.
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post #23 of 141 Old 05-20-2013, 09:40 PM
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Tv only has 2 point controls.A meter does not prevent the bright white patches from going super bright.I would think every plasma is a little bit different in how it determines brightness and gamma of the brightest patches...The better I've got it looking the more I've been able too live with this problem.Its a problem,but not as much as a tv that's too dim.

You can use dynamic range tools to measure how quickly the signal is increasing. You can be more analytical adjusting contrast to quantify the amount of light you'd compromise.

It all comes down to how much your time is worth. You can keep grinding away trying to do it by eye, or you can get a meter and start discovering the facts of your situation.

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post #24 of 141 Old 05-21-2013, 12:49 PM
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Tv only has 2 point controls.A meter does not prevent the bright white patches from going super bright.I would think every plasma is a little bit different in how it determines brightness and gamma of the brightest patches...The better I've got it looking the more I've been able too live with this problem.Its a problem,but not as much as a tv that's too dim.

A meter helps you get the right settings for each control. The contrast control sets how bright white is. 35 fL or so is what you want 100% white to measure in a dark room. Without a meter, you'll never know if you are looking at 15 fL or 25 fL or 50 fL or 90 fL... you have no clue. You won't get past the bad appearance until you know what you have and whether you are even remotely close to having the right settings. The only controls a meter won't help you with is the Brightness control that sets the black level and the Sharpness control that adds artifacts to images or "de-focuses" images in some cases. You have to use test patterns to set those 2 controls. But you set Contrast using a meter (to get 35 fL for viewing in a dark room), and you set your color management controls and gains/offsets to get color as accurate as it can be and grayscale as accurate as it can be. None of that can be done by eye. I can't do it by eye and I have 34 years of engineering experience with some highly sophisticated imaging systems and 6 years of experience measuring and calibrating home theater video displays (which is like 2+2=4 after the professional imaging systems I've worked on). Eventually, you'll understand this, but only if you keep studying and learning more about calibration and how human vision works (it's far from infallible).

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post #25 of 141 Old 05-21-2013, 04:45 PM - Thread Starter
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The article that reviewed iPad said if you put the light level control at halfway that it produces 30 footlamberts and images of 100% white is 39 footlamberts.So I put video essentials 100% white box on screen and try too make it as close to same look as a pure white screen on iPad.
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post #26 of 141 Old 05-21-2013, 10:13 PM
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Quote:
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The article that reviewed iPad said if you put the light level control at halfway that it produces 30 footlamberts and images of 100% white is 39 footlamberts.So I put video essentials 100% white box on screen and try too make it as close to same look as a pure white screen on iPad.

Still doesn't work unless you construct a proper Optical Comparator ... and even then if you don't match the Y of the display and the target, you'll get dubious results.

For instance, if the Y (luminance) of your display is less than the Y of the target, you will be probably end up adding too much blue to compensate for the difference.

You can literally chase these things for YEARS ... or you can invest in the proper equipment and get it dialed in a couple of hours.

Furthermore, given the availability of rental options, there's really no excuse for continuing to flail about in the dark.
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post #27 of 141 Old 05-22-2013, 01:04 PM
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Still doesn't work unless you construct a proper Optical Comparator ... and even then if you don't match the Y of the display and the target, you'll get dubious results.

For instance, if the Y (luminance) of your display is less than the Y of the target, you will be probably end up adding too much blue to compensate for the difference.

You can literally chase these things for YEARS ... or you can invest in the proper equipment and get it dialed in a couple of hours.

Furthermore, given the availability of rental options, there's really no excuse for continuing to flail about in the dark.

Try this: https://itunes.apple.com/us/app/isf-hdtv-professional-calibrator/id518987879?mt=8

A nifty app for the Ipad for $9.99! From ISF so not a joke.
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post #28 of 141 Old 05-22-2013, 01:35 PM
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I just measured my iPad.

With the brightness slider in the middle, it measures 20 fL, not 30.

the x measurement was .3083
the y measurement was .3216

d65, the calibration standard, has an x coordinate of .3127 and a y coordinate of .3290.

The dE (delta E) error calculates to 4 or 6 depending on which method of error calculation you use. In either case, those are visible errors. Human vision can detect a dE of 1 in a still image with a reference image next to it that is correct. In moving video images, it is difficult to detect errors in the range of 3 or less, but above 3, the errors become increasingly visible. Anybody can/should see an error of 10, even without training.

The inaccuracy of the iPad makes it about 8% too blue so your TV will be misadjusted by 8% too blue if you use the iPad as a reference... and that assumes all iPads measure the same. Then there's the viewing angle issue... the iPad has an LCD display so any viewing angle that is not straight-on to the iPad will produce a shift that causes white to get dimmer (and shift color somewhat) and black to get brighter. So measuring an iPad you have to align the meter PRECISELY with the iPad so there's no off-axis component that will throw off the measurement or comparison.

I've never seen a measurement study of a fair number of iPads from each generation... original, 2, 3, 4, etc. There are differences in appearance and certainly in measurements. You'd want to measure 25-50 samples of each model of iPad to draw any conclusions about how consistent each model is when compared to each other AND to determine how close (or far) they are from the d65 video standard. You could get away with 25 samples if the range of readings was fairly small/tight, but if there's more variation in readings, you'd need 50 or more samples to know what was going on. Being 8% too blue is not an acceptable reference standard.
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post #29 of 141 Old 05-22-2013, 10:41 PM - Thread Starter
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]Thanks for doing that.Mine is the iPad 1.The study was on ipad3.I think more recent ipads are a warmer temperature from what they originally were.ill have to check check for sure.

What iPad is yours? And is that 20 fl a measurement for an all white window like if you press the + symbol to open new window?
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post #30 of 141 Old 05-22-2013, 11:25 PM
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Quote:
Originally Posted by subraman View Post

Try this: https://itunes.apple.com/us/app/isf-hdtv-professional-calibrator/id518987879?mt=8

A nifty app for the Ipad for $9.99! From ISF so not a joke.

Looks like a pretty mediocre effort that ignores every optical comparator bug-a-boo. Also it looks like somebody just slapped the initials "ISF" on a GIF pattern. I guess if you're trying to pick between Warm1, Warm2, Medium or Cool presets then it might have *some* merit, but as a serious calibration tool, it is worthless.

Rule #1 For an Optical Comparator to work properly: There can be NO gap between the target on the display and the reference target on the Comparator. The iPad has an opaque frame ... thus there is no possible way to have the targets "meet" ... thus it will fail this rule 100% of the time.

Carry on ...

PS: OTOH, I guess you get what you pay for. Personally, I'd rather spend that $10 on a couple of slices of pizza ... or a few adult beverages ... same calibration results either way. wink.gif
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