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I use a BNC-DVI cable so obviously i won't get EDID information but i have the driver installed but when i select it, it goes blank for a second and switches back to 2048x1536 max resolution and 120Hz max refresh rate; even when i lower it to, for example, 1920x1200 it goes back to 2048x1536 (in the CCC and in the windows resolution setting).
Adding any resolution higher than 2048x1536 won't show up in windows. I had a newer catalyst beta driver installed but even going back to an older one on which it worked didn't help.
I have no idea why it suddenly won't work anymore
done
According to the manual, it does have an automatic adjustment protocol, and you can set the tolerances of x,y, and Y independently.
from the manual:
Then again, I've never actually used the software, so I can't be sure.
The CS-2000 is a BEAUTIFUL instrument. I wish I could work with one
I like the WinDAS white point balance test - it allows you to slide the contrast level and see how the chromaticity changes, so it gives you an idea of how well the grayscale tracks.
One thing that many calibrators do, when testing grayscale tracking (white point balance across the range of luminance) is do a systematic test from 0% to 100% luminance, usually in 10 percent intervals, and record delta E's at each of those 10 points. Due to display and instrument limitations, you'll rarely see low delta E's at the very low luminance levels. Even on a high end Sony trimaster OLED, the WPB doesn't track perfectly below 0.1 cd/m2 (see fig 11 of this recent open access paper from journal of vision.
Here's an example of how grayscale tracking can be reported. This was a special calibration done by Scott Wilkinson and Robert Heron on a high end OLED tv (Samsung KN55S9C, close to $10,000) owned by Leo Laporte.
Notice in this figure that the average delta E was 2.28 which is still considered very good (although their other instrument reported delta E's below 1).
Here's the video of the entire calibration process.
Keep in mind that those delta E's are simply delta E's relative to the chromaticity of D65.
Delta E is used in many contexts - when measuring the quality of an instrument, Delta E refers to the difference of that instrument relative to a lab-grade reference instrument. Delta E can also be used to refer to repeatability measurements within the same instrument, or between instruments of the same model.
When reporting Delta E's in the context of display calibration, it's done with reference to a particular standard. In the case of HD video, that standard is Rec 709.
With computer displays, it can be tricky to report these results, since the software that does the measurements typically run in a windows or OSX environment, and there may be weak links in the display pipeline that alter the final signal. With a signal generator, you can be certain that what you see reflects the monitor's output at its most basic operating level.
Once you introduce video cards, operating system, and test pattern software, there is the risk of all those components changing the original signal.
There are a couple ways to deal with this, however. One is to really manage your operating system and software environment carefully, to ensure that there are no weak links in the pipeline. One can confirm whether this is done successfully by measuring test patterns in signal generator environment and comparing the x,y,Y readings to those obtained when measuring the same test patterns in a windows+software environment. If they are the same, then one can proceed with a degree of confidence. Vito, or anyone else: if you end up doing this experiment, I'd be very curious to learn the results!
The other way is to actually measure the x,y,Y values at different IRE's using the signal generator, and then record the values (from 0% to 100% or whatever you choose). You can then open up HCFR, and input those values into the grayscale measurement tab (check the box called "editable data"), and it will automatically calculate the Delta E's at each luminance level that you input.
Here, this is written by Yoshi Ohno, whose expertise I trust over just about anyone.
Do you understand that the i1 pro measures both emmisive sources, and object sources (referred to in the xrite terminology as display measurement and spot measurement), and is therefore, according to the authoritative definition I have provided, both a spectroradiometer and a spectrophotometer?
I understand it's confusing, as usually the term radiometric and photometric are distinguished in that one involves radiometric quantities, such as radiant flux (in watts), and the other involves photometric quantities such as luminous flux (lumens), and in order to convert from one to the other you have to take into account the spectral luminous efficiency function.
So one might think that a spectroradiometer measures radiance, while a spectrophotometer measures luminance.
But this is not what separates the two. Converting from radiance to luminance is not a function of the optics or the hardware of the instrument, it is a simple mathematical function that is applied to the Spectral Power Distribution (SPD).
I can actually measure SPD's using my i1 pro:
this is what it looks like (courtesy of Zoyd, who took the measurements in HCFR with his i1pro):
Another point of confusion is that people often use the terms spectroradiometer and spectrophotometer interchangeably, but, according to the authoritative source, a spectroradiometer measures a test light directly, whereas a spectrophotometer uses a reference light to illuminate a test sample, then reads the reflected light off that sample. The combination of the reference illuminant and the spectral reflectance factor of the sample will determine the final reading.
In this sense, a spectrophotometer is actually more sophisticated than a spectroradiometer, as a spectroradiometer has to only measure incoming light, whereas a spectrophotometer has to both generate a reference illuminant, and read the reflected light.