Massive Color Drift Correction for i1 Display Colorimeter - Page 2 - AVS Forum
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post #31 of 95 Old 04-18-2012, 04:45 PM - Thread Starter
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Originally Posted by sotti View Post

The same thing could be of any market.

I'm sure digital photographers routinely disparage any camera sold for less than $500, yet millions of people take pictures and enjoy them.

What bothers me is the industry color leader is using professional photographers and videographers to sell there calibration products. This is without any instrument specifications nor any guarantees of accuracy. X-rite says "In our world, perfection is not too much to ask for. i1Display Pro delivers." BTW, the specifications tab on the X-rite site for this product describes only the OS that the software will work with, nothing about the instrument. I guess this is good enough for the Apple/iPad like "click once" and it's done people!
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post #32 of 95 Old 04-18-2012, 04:55 PM - Thread Starter
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Originally Posted by sotti View Post

The issue is that the i1 Display 2 is a 6 or 7 year old design that replaced meters that were even older.

I have cheap Radio Shack meter that is over 20 years old, yet it still is useable for low precision work. If the the i1DisplayLT relies on a stable red filter then why is it so difficult to keep stable. After all the Blue and Green filters seem to have little or no problems with drift. This is a chemical dye issue that should have been corrected 5-6 years ago. Nothing else in the meter would account for a 60% error.
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post #33 of 95 Old 04-18-2012, 05:06 PM
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Originally Posted by Plasma54321 View Post

I have cheap Radio Shack meter that is over 20 years old, yet it still is useable for low precision work. If the the i1DisplayLT relies on a stable red filter then why is it so difficult to keep stable. After all the Blue and Green filters seem to have little or no problems with drift. This is a chemical dye issue that should have been corrected 5-6 years ago. Nothing else in the meter would account for a 60% error.

Colorimeters are a new thing, they had volt meters 100 years ago, and my guess is a good reliable volt meter was not an inexpensive item.

It may not be the red filter, it may be the blue and green. Either way the same reason the filters go bad is the same reason these meters were affordable in the first place. They were cheap filters. The glass ones in a Klien K-10 cost more than a case of i1 Display 2s.

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post #34 of 95 Old 04-18-2012, 06:36 PM - Thread Starter
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Originally Posted by sotti View Post

It may not be the red filter, it may be the blue and green.

So the blue and green filters failed and only the red is valid. Then why is my red luminance value down more than 60%. Why? How? This misinformation is not acceptable. So the only good meter is $10K. Then X-rite should state that fact. This is the standard argument - blue filters are not good. Get a colorimeter they are not good. Get a spectrophotometer but not a $1K one only a $10k one.

I am talking about a 60% error in less than 4 years of limited use. That is advertised for accurate professional use.
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post #35 of 95 Old 04-18-2012, 06:51 PM
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Originally Posted by Plasma54321 View Post


I am talking about a 60% error in less than 4 years of limited use. That is advertised for accurate professional use.

And a Washing machine should last 20 years .. and a TV should last 20 years but that Flat screen you paid $3000 4 years ago is now dead in the land fill.. With most tools and test instruments you get what you pay for.. I bought a new C6 (i1display 3) because it has sealed optics and they think it will last longer than the older design in the i1dispay2. I then bought a used i1Pro because I wanted a more accurate meter than just the colorimeter with tables.. Will the C6 be junk in 4 years, no one knows.. It sucks that stuff is not made to last for year and years but that is the way the economy is designed.. Everyone wants stuff CHEAP and you don't get the top of the line anything CHEAP
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post #36 of 95 Old 04-18-2012, 06:52 PM
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Originally Posted by Plasma54321 View Post

So the blue and green filters failed and only the red is valid. Then why is my red luminance value down more than 60%. Why? How? This misinformation is not acceptable. So the only good meter is $10K. Then X-rite should state that fact. This is the standard argument - blue filters are not good. Get a colorimeter they are not good. Get a spectrophotometer but not a $1K one only a $10k one.

I am talking about a 60% error in less than 4 years of limited use. That is advertised for accurate professional use.

if you store the meter in an airtight case with a high-quality desiccant and keep it away from light, heat, and moisture you can get more consistent results over time

I suggest you take another look at this article as it really does make a difference.

also, if you plan on buying another colorimeter in the near future, go for a sealed optics design like with the D3 family of meters
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post #37 of 95 Old 04-18-2012, 06:59 PM
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Originally Posted by airscapes View Post

And a Washing machine should last 20 years .. and a TV should last 20 years but that Flat screen you paid $3000 4 years ago is now dead in the land fill.. With most tools and test instruments you get what you pay for.. I bought a new C6 (i1display 3) because it has sealed optics and they think it will last longer than the older design in the i1dispay2. I then bought a used i1Pro because I wanted a more accurate meter than just the colorimeter with tables.. Will the C6 be junk in 4 years, no one knows.. It sucks that stuff is not made to last for year and years but that is the way the economy is designed.. Everyone wants stuff CHEAP and you don't get the top of the line anything CHEAP

+1, very true

for example, who knows how long the LED backlights in modern displays will last? only time will tell

the sealed optics of the D3 should give it a huge advantage over the D2 or the spyder family of meters that directly expose the filter array... just like the design on high end meters for professional use
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post #38 of 95 Old 04-18-2012, 08:03 PM
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Originally Posted by Plasma54321 View Post

So the blue and green filters failed and only the red is valid. Then why is my red luminance value down more than 60%. Why? How? This misinformation is not acceptable. So the only good meter is $10K. Then X-rite should state that fact. This is the standard argument - blue filters are not good. Get a colorimeter they are not good. Get a spectrophotometer but not a $1K one only a $10k one.

I am talking about a 60% error in less than 4 years of limited use. That is advertised for accurate professional use.

I've never heard that the i1 Display 2 is considered professional equipment.

The i1 Pro is x-rite's most "Professional" piece of equipment. The i1 Pro is an extremely reliable piece of equipment, we've seen those meters come through our lab 4 years old and still within original spec.

The i1 Pro is a great tool it's easily accurate enough for any consumer uses. Also they make the colormunki spectro that is a cut down version of the i1 Pro. Not nearly as good in reflective mode, but fairly comparable for emmisive use.

Granted in 2008 when you bought your meter, only the i1 Pro was available and they were selling in the vicinity of $2000, now you can find used ones on ebay for <$500 and the colormunki spectro new on amazon for $450.

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post #39 of 95 Old 04-18-2012, 09:16 PM
 
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Originally Posted by airscapes View Post

And a Washing machine should last 20 years .. and a TV should last 20 years but that Flat screen you paid $3000 4 years ago is now dead in the land fill.. With most tools and test instruments you get what you pay for.. I bought a new C6 (i1display 3) because it has sealed optics and they think it will last longer than the older design in the i1dispay2. I then bought a used i1Pro because I wanted a more accurate meter than just the colorimeter with tables.. Will the C6 be junk in 4 years, no one knows.. It sucks that stuff is not made to last for year and years but that is the way the economy is designed.. Everyone wants stuff CHEAP and you don't get the top of the line anything CHEAP

I don't know about wanting something for "cheap", but when the D2 came out it was what was available and lauded at least as much as the D3/C6 is now. So, as you say. . . "who knows"?

And the way the economy is, some of us may take the plunge once to get a colorimeter, but if it turns into junk, do not care to risk further resources. So you can't fault a person for that.

And if the D2 had unsealed filters subject to premature failure, then the product may not have been ready to market. Or else the vendor knew it and , as I said previously, figured on a hobbyist using it a few times, loosing interest, and then "who cares". Either way, not much integrity there.

And to expect a person to buy both a colorimeter, software and updates, and a spectro. . . Why shouldn't the one product be enough? It isn't sold in a package that way or disclosed as a requirement.

To be fair, if that's what a person is ok with then fine for them. I personally feel burned that my D2 was unreliable too. Last I checked they are on Ebay regularly for $45 to $60.

I'll be watching to see how the D3/C6 ages.
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post #40 of 95 Old 04-19-2012, 03:53 AM
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Quote:
Originally Posted by sotti View Post

The i1 Pro is a great tool it's easily accurate enough for any consumer uses. Also they make the colormunki spectro that is a cut down version of the i1 Pro. Not nearly as good in reflective mode, but fairly comparable for emmisive use.

sotti, I assume this model ColorMunki is what you are talking about?
ebay
The physical design doesn't look too suitable for projector profiling but the product details include using it with projectors.

You mention that the ColorMunki spectro isn't good for reflective mode, I assume you mean measured off the screen (ie. its better 'looking' into the projector lens). Would a ColorMunki spectro be suitable for training an i1 (to adjust its profile table to ensure it reads accurately) and using the i1 for the projector measurements?
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post #41 of 95 Old 04-19-2012, 08:55 AM
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Originally Posted by deandob View Post

sotti, I assume this model ColorMunki is what you are talking about?
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The physical design doesn't look too suitable for projector profiling but the product details include using it with projectors.

It works fine with projectors, but mostly just for reading odd the screen, I don't believe it has an illuminant head like the i1 Pro does for reading directly from the projector.

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Originally Posted by deandob View Post

You mention that the ColorMunki spectro isn't good for reflective mode, I assume you mean measured off the screen.

Not quite, I was referring to it's use to measure printed materials. The i1 Pro has a tungsten lamp which corresponds directly to illuminant A, making color measurement very accurate. The munki has I believe a doped up LED, this makes a big difference in the accuracy of measuring printed materials where the internal lamp is the only light source.

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post #42 of 95 Old 04-19-2012, 01:47 PM - Thread Starter
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Originally Posted by sotti View Post

I've never heard that the i1 Display 2 is considered professional equipment.

This is a direct quote from the side of my box for the meter:

"Designed to meet the needs of creative professionals and discerning digital imaging enthusiasts. Eye-One Display LT ensures reliable and accurate color onscreen. With the easy-to-use software wizard, you'll achieve consistent predictable color on all types of monitors - LCD, CRT and laptops - with a few simple clicks."

That sounds like people seriously interested in getting "good" results.

The product is DISCONTINUED on the X-rites site. There are no specifications for either this meter nor the i1 Display Pro.

In fact, the only specs that I have ever seen were on Spectracal's site. Probably, after they tested and ensured the X-rite product. I applaud the attempt to objectively quantify the accuracy of the device. X-rite doesn't want to! That is not good!
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post #43 of 95 Old 04-19-2012, 02:16 PM
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Quote:
Originally Posted by Plasma54321 View Post

This is a direct quote from the side of my box for the meter:

"Designed to meet the needs of creative professionals and discerning digital imaging enthusiasts. Eye-One Display LT ensures reliable and accurate color onscreen. With the easy-to-use software wizard, you'll achieve consistent predictable color on all types of monitors - LCD, CRT and laptops - with a few simple clicks."

That sounds like people seriously interested in getting "good" results.

Unfortunately that is what marketing is all about! Would you buy something that said, This is a poor quality, low priced device and it is only good for DIY users!"?

I agree with you 100% that products should last many many years and not be made so poorly that fail or become inaccurate quickly. I would probably feel the same way you do if I were in your shoes. This is one thing that is great about the internet and sites like this one, with sufficient time invested anyone can do the needed research to know more about a product than what the manufacture tells us.

As to the marketing.. here are 375 products sold by Harbor Freight that claim to be for professionals..
http://www.harborfreight.com/catalog...q=professional
Nothing sold by Harbor Freight is a serious quality product, I own many of them. I know they are inexpensive replicas of good stuff and they will fail but if I get 2 or 3 uses out of them I have gotten my money's worth.

Think of you i1D2 in that way. You got a couple of calibrations out of it, and you learned how to calibrate. You would have paid a pro more than you spent to do several calibrations. After all isn't that why we buy our own tools and do things ourselves, to save money and have that feeling of accomplishment?
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post #44 of 95 Old 04-19-2012, 03:10 PM
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Quote:
Originally Posted by Plasma54321 View Post

This is a direct quote from the side of my box for the meter:

"Designed to meet the needs of creative professionals and discerning digital imaging enthusiasts. Eye-One Display LT ensures reliable and accurate color onscreen. With the easy-to-use software wizard, you'll achieve consistent predictable color on all types of monitors - LCD, CRT and laptops - with a few simple clicks."

That sounds like people seriously interested in getting "good" results.

The product is DISCONTINUED on the X-rites site. There are no specifications for either this meter nor the i1 Display Pro.

In fact, the only specs that I have ever seen were on Spectracal's site. Probably, after they tested and ensured the X-rite product. I applaud the attempt to objectively quantify the accuracy of the device. X-rite doesn't want to! That is not good!

I'm sorry you're having serious issues with your meter, but it would be naive to believe everything the marketing folks tell you about a product. The D2 is not a professional grade meter and many professional calibrators would consider it to be an very error prone meter. I had somewhat better results with the CalMAN enhanced 'X2' version of this meter, but ultimately I upgraded to the D3 family of meters.
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post #45 of 95 Old 04-19-2012, 03:11 PM
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Originally Posted by sotti View Post

It works fine with projectors, but mostly just for reading odd the screen, I don't believe it has an illuminant head like the i1 Pro does for reading directly from the projector.

Thanks, so it sounds like the colormunki should do just fine then for training an i1 for projector calibration.
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post #46 of 95 Old 04-19-2012, 03:15 PM
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Originally Posted by airscapes View Post

Unfortunately that is what marketing is all about! Would you buy something that said, This is a poor quality, low priced device and it is only good for DIY users!"?

I agree with you 100% that products should last many many years and not be made so poorly that fail or become inaccurate quickly. I would probably feel the same way you do if I were in your shoes. This is one thing that is great about the internet and sites like this one, with sufficient time invested anyone can do the needed research to know more about a product than what the manufacture tells us.

As to the marketing.. here are 375 products sold by Harbor Freight that claim to be for professionals..
http://www.harborfreight.com/catalog...q=professional
Nothing sold by Harbor Freight is a serious quality product, I own many of them. I know they are inexpensive replicas of good stuff and they will fail but if I get 2 or 3 uses out of them I have gotten my money's worth.

Think of you i1D2 in that way. You got a couple of calibrations out of it, and you learned how to calibrate. You would have paid a pro more than you spent to do several calibrations. After all isn't that why we buy our own tools and do things ourselves, to save money and have that feeling of accomplishment?

+1, I agree with these points and this applies to any product in any market
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post #47 of 95 Old 04-19-2012, 03:49 PM
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Originally Posted by deandob View Post

Thanks, so it sounds like the colormunki should do just fine then for training an i1 for projector calibration.

Yes it would work very well.

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post #48 of 95 Old 04-19-2012, 03:59 PM - Thread Starter
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I want to refocus to the original thread questions (below):

I recently tried measuring both a new Westinghouse VR-3730 LCD HDTV and my older Panasonic 42PZ85 plasma HDTV. I used my i1 Display LT colorimeter with HCFR software, only to find a large RED color shift. The subjective PQ looks OK but the i1 is reading RED at about 50-60% lower than what I would be expecting.

I directly compared an older data file of my Panasonic TV with a new one at the same TV settings. The luminance and gamma charts are quite similar but the RGB levels, color temperature and CIE diagrams are different or shifted, especially WRT red values.

Is this magnitude of drift error that others have experienced with i1Display colorimeters? Or is there something else that is the problem?

Can HCFR software null this error out? Is this feature within its capabilities?[/


I have included my HCFR data charts to objectively describe what I am observing. The following charts contain data from my Panasonic 42PZ85 plasma HDTV from OLD=2/20/2010 and NEW=4/8/2012 under the same test conditions. The SOLID lines are the NEW data and the DASHED (reference) lines are OLD.

The luminance and gamma are fairly similar, but all the rest of the charts (RGB levels, Color Temperature and CIE Diagram) indicate large discrepancies. Can something be done to correct or compensate for this in HCFR? Is this what others have seen for i1 Display 2/LT meter drift?









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post #49 of 95 Old 04-19-2012, 04:37 PM
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Yes, this is a similar result I got when both my i1 LT's drifted. As per my posts above, my fix is going to be to purchase a second hand colormunki spectro (which is much more stable over time but no good for low light measurements) and train my drifted LT to the spectro so that the offset tables will cancel out the drift.

You can also read earlier threads I started about using an alternative color reference to adjust the offset tables but the only reasonable way I could work out was to use a second projector bulb that is stored away as a reference (the delta between an old reading and a current reading is the meter drift) but that is too much hassle and not guaranteed.
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post #50 of 95 Old 04-19-2012, 04:55 PM
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Quote:
Originally Posted by deandob View Post

Yes, this is a similar result I got when both my i1 LT's drifted. As per my posts above, my fix is going to be to purchase a second hand colormunki spectro (which is much more stable over time but no good for low light measurements) and train my drifted LT to the spectro so that the offset tables will cancel out the drift.

You can also read earlier threads I started about using an alternative color reference to adjust the offset tables but the only reasonable way I could work out was to use a second projector bulb that is stored away as a reference (the delta between an old reading and a current reading is the meter drift) but that is too much hassle and not guaranteed.

isn't it possible though for the meter to drift so far than it cannot be profiled successfully?
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post #51 of 95 Old 04-19-2012, 06:05 PM
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isn't it possible though for the meter to drift so far than it cannot be profiled successfully?

At some point that could become more of an issue, but as long as they are reading data that is remotely sane, it should be fine.

You can always double check the readings against the spectro to see if they line up.

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post #52 of 95 Old 04-19-2012, 06:05 PM
 
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Originally Posted by airscapes View Post

Nothing sold by Harbor Freight is a serious quality product, I own many of them. I know they are inexpensive replicas of good stuff and they will fail but if I get 2 or 3 uses out of them I have gotten my money's worth.

Think of you i1D2 in that way. You got a couple of calibrations out of it, and you learned how to calibrate. You would have paid a pro more than you spent to do several calibrations. After all isn't that why we buy our own tools and do things ourselves, to save money and have that feeling of accomplishment?

On the other hand, I have many Sears Craftsman tools which were inexpensive from many years ago and still work fine after some being abused on auto repairs from times when funds were limited and repairs were done "under the shade tree". Given that analogy, it is not unreasonable to expect the same kind of return on investment on a $200 (original price) meter.
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post #53 of 95 Old 04-20-2012, 01:46 AM
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On the other hand, I have many Sears Craftsman tools which were inexpensive from many years ago and still work fine after some being abused on auto repairs from times when funds were limited and repairs were done "under the shade tree". Given that analogy, it is not unreasonable to expect the same kind of return on investment on a $200 (original price) meter.

The durability of inexpensive, forged/hardened tools in no way relates to the long-term accuracy of an inexpensively made sensor designed to measure certain qualities of light. As someone who has supposedly worked with "pro-grade" calibration equipment before, I'd think you'd understand and respect that massive difference, as well as the massive difference between a $200 colorimeter and something several orders of magnitude more expensive that is used by professionals.

There are 10 types of people: those who understand binary, and those who don't.

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post #54 of 95 Old 04-20-2012, 06:18 AM - Thread Starter
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Originally Posted by deandob View Post

Yes, this is a similar result I got when both my i1 LT's drifted.

So you saw about a dE=40-50 shift in color error in 12-18 months. I trying to quantify what people have actually measured and over a definite time period.

In my case, the (see above) reference plots were 26 months apart and have massive RED filter error with normal storage.
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post #55 of 95 Old 04-20-2012, 06:27 AM - Thread Starter
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I am still confused as to why the luminance and gamma plots look so similar. The luminance plots are all most on top of each other. The gamma has some differences with the RED data darker (gamma higher) for most of the chart with the exception of 90% point.

Why are is this data reasonably good, when the RGB Levels, color temperature,and CIE diagram data clearly indicate a big problem?

What am I missing?

How would you adjust or correct for this in HCFR? Can an Excel spreadsheet be used to adjust things?
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post #56 of 95 Old 04-20-2012, 06:31 AM
 
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Originally Posted by HogPilot View Post

The durability of inexpensive, forged/hardened tools in no way relates to the long-term accuracy of an inexpensively made sensor designed to measure certain qualities of light. As someone who has supposedly worked with "pro-grade" calibration equipment before, I'd think you'd understand and respect that massive difference, as well as the massive difference between a $200 colorimeter and something several orders of magnitude more expensive that is used by professionals.

Just following up on Airscapes' comment about Harbor Freight tools. Interesting you would seek out and have to comment ONLY on my post.

Typical though.
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post #57 of 95 Old 04-20-2012, 06:45 AM
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I don't know exactly the magnitude of the shift but the red decrease was very visible to the naked eye making the picture look green / turquoise (the green was more obvious than the blue when the picture was red deficient). Sorry I don't have actual dE values but I would guess 15+
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post #58 of 95 Old 04-20-2012, 08:06 AM
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Quote:
Originally Posted by Plasma54321 View Post

I am still confused as to why the luminance and gamma plots look so similar. The luminance plots are all most on top of each other. The gamma has some differences with the RED data darker (gamma higher) for most of the chart with the exception of 90% point.

Why are is this data reasonably good, when the RGB Levels, color temperature,and CIE diagram data clearly indicate a big problem?

What am I missing?

How would you adjust or correct for this in HCFR? Can an Excel spreadsheet be used to adjust things?

Luminance and RGB are 2 different things. The meter can read the proper brightness (amount of light or luminance) correctly but not the proper color.
Gamma is the difference in luminance form 0 -100% and has nothing to do with color, so it can be accurate and the color reading be very wrong. You can not fix this without using a known good reference spectror meter, and if you had such a meter, you would probably just toss the D2 in the trash and use the spectro since the speed difference would be of no great issue.

If you are not familiar with meter profiling this is something that is done in the software if it support it. I have no idea what HCFR support.
To profile a meter:
The software tell you to ready your reference meter and you place it so it is looking at a known spot on the screen, hopefully taking into account Field of view difference between the 2 types of meters.

Then you display a Red, Green, Blue and white pattern and take readings of each.

Next you set up the target meter that you want to make better so it sees the same spot on the screen.

You do the same readings on the target meter.

The software makes a table of the difference between what the reference meter sees vs what the target meter sees.

This difference table is then applied to all readings made by the target meter during the calibration.

This fix is only accurate on this one display where the reading were taken.

Hope that clears it up.
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post #59 of 95 Old 04-20-2012, 10:35 AM
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Quote:
Originally Posted by HogPilot View Post

The durability of inexpensive, forged/hardened tools in no way relates to the long-term accuracy of an inexpensively made sensor designed to measure certain qualities of light. As someone who has supposedly worked with "pro-grade" calibration equipment before, I'd think you'd understand and respect that massive difference, as well as the massive difference between a $200 colorimeter and something several orders of magnitude more expensive that is used by professionals.

+1, well said

Quote:
Originally Posted by Phase700B View Post

Just following up on Plasma54321 comment about Harbor Freight tools. Interesting you would seek out and have to comment ONLY on my post.

Typical though.

so is your reaction to HogPilot's post; this is an open discussion thread, not private messaging
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post #60 of 95 Old 04-20-2012, 10:38 AM
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I'll say it again, proper storage of these meters is essential to maximizing their lifespan (especially for those meters with completely exposed filter arrays). I'm not sure the OP's storage method was 100% optimal.
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