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Discussion Starter #1
I purchased i1Pro (revision D I think) some time ago and I think it was plain defective. It kept showing that my i1Display Pro was measuring/calibrating Blue 10% below of where it should be for each and every grayscale levels. All my i1Display Pro calibrations that showed Blue @ 100% for every grayscale level were shown to lack 10% Blue for every grayscale level on EVERY display type and displays I had! I had actually had TWO i1Display Pro devices and they both measured grayscale with identical results.

When I profiled i1Display Pro with i1Pro (and I did follow all instructions precisely), my results were very mixed. On one display, a TN panel, profiling fixed the slight red tint that resulted after previous calibration by UN-profiled i1Display Pro. That seemed right, but then my VA panel calibration with profile i1Display Pro results in a VERY obvious blue tint that was not present when I used UN-profiled i1Display Pro. The same thing happened to my plasma after profiling my i1Display Pro with i1Pro and calibration it - there was an obvious blue tint!

So it fixed my red tint on TN panel, but messed up other displays. I don't know what to think. Was it defective? There was a big thread, started by someone, that showed some research about i1Pro being LESS accurate than i1Display Pro in many cases...
 

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Ditto the questions from JimP.

It is possible that your i1Pro is bad. You should have a base for it with a white ceramic tile in it. The base serial number should match the serial number of the i1Pro. When the units are made, they calibrate it to the individual white tile as a set. It is possible that the unit has been dropped, or worse, opened, and the diffraction grating has been damaged or offset some how. Usually though, if it is bad, it will not pass self-check and calibration to its reference tile.

However, if you use the software tool from XRite and run the calibration report, it should say whether it passes or not, and also give you the number of seconds the bulb has been run in the unit and some other information about it. If all that is good, you should have a functional unit.

If you are using software that can display the measured spectra from the i1Pro, you may be able to check it against some known light sources. For instance, if you have low-pressure sodium (yellow-orange) street lights in your neighborhood, you can stand underneath one and aim the i1Pro at it. The yellow colored light from these lamps is pretty much a single spike at 589nm. If you have software that can display the spectrum the i1Pro measures, you can easily verify that it is at least working.

It is not unusual though for a correctly working i1Pro and i1Display Pro to differ from each other. This depends a lot on the particular display technology, the character of the spectrum of light it emits and whether you have a proper calibration file for the display technology for the i1Display-Pro.

Generally, the process is to characterize the display at high brightness with the spectroradiometer (the i1Pro) and create a correction matrix so your colorimeter (the i1-Display Pro) agrees with it. Then use the colorimeter to set the white balance. Generally, the spectroradiometer is better at measuring an accurate color temperature, but it is much slower and not as accurate at low light levels. Once the colorimeter is corrected in software to agree with the spectral device, it is generally much faster at acquiring the light data and better at measuring color at low light levels.
 

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too add to the info already given,
I found contact mode for making profiles is trouble some.
The field of view is so small that a good read is iffy.
using a tripod and making the I1pro 38% farther away than the I1D3 gave a good read.

if you do not have a tripod, use something to move the pro off the screen, like a chalk board eraser or something soft and thick that can keep it flat but away.

let it warm up by being plugged in and take a couple runs before using it to profile.

also, using a powered USB hub will help the I1pro.
 

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Really how far i need to place the i1 pro to measure away from the screen? and if i do this i will get less ftl right? so far im trying to be to max 40ftl.
Ted (Teds lightspace disk) tested FOV and used 7 inches for the I1pro and 5.35 for the I1display 3.
7 times .235 (23.5% not 38%) equals 1.645
7-1.645=5.355
if I copied his distances wrong, someone correct me.

Calman tested and suggests 30%

I found 38% when the I1pro is 10 inches and display 3 is 6.2 inches
works well. I have experimented with up to 50% and down to 20%.
30% works well.

no ftl should be similar
 

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Discussion Starter #10
My i1Pro was used. I purchased it off eBay, but it was in excellent condition from a seller with a ton of positives and no negatives. I ran diagnostics and they were all successful. My unit came with base and all necessary peripherals and components. I tried using several applications - HCFR Calibration, ArgyllCMS 1.7.0 + dispcalGUI 3.0.0 package, and of course the latest SpectraCal CalMAN 5.20 Enthusiast Edition. They all produced identical results as far as correction matrices went. I know I created correction matrices correctly, following all instructions, profiling each display device separately, although resulting correction matrices for each display device were close to identical within a marginal difference. I do not want to sound rude or ungrateful, but I am aware of how spectrometers differ from colorimeters and about their strengths and weaknesses. I am not a pro, but I consider myself knowledgeable enthusiast (with very little money to afford anything beyond i1Display Pro and used i1Pro...). I've been calibrating TV's with my i1Display Pro locally and I never had any trouble with any set. I learned most of it from here and many guides, but I only know started to have questions, for which I could not find answers.

The TN panel, for which i1Pro seemed to work well, eliminating the red tint was ASUS VG248QE, one of them LightBoost monitors, a lot like ASUS ROG. The other devices were 2011 Samsung SPVA CCFL LCD HDTV and Samsung PNF5300 plasma. On these other devices, i1Pro correction matrix/profiling and calibration using that profiling resulted in an obvious blue tint across the entire grayscale, just like I stated in the OP.

It was most likely a bad unit or maybe i1Display Pro's tables for those devices were more accurate than i1Pro's light readings.

Thanks for all your responses!
 
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