Luminous Landscape Forum

Raw & Post Processing, Printing => Colour Management => Topic started by: AlterEgo on May 06, 2015, 11:38:23 am

Title: i1DPro, i1Pro2, argyll and .ccss calibration spectral samples...
Post by: AlterEgo on May 06, 2015, 11:38:23 am
http://www.argyllcms.com/doc/ccxxmake.html says

Quote
For Colorimeters that have sensor spectral sensitivity calibration information built into them  (ie. the X-Rite i1d3, and DataColor Spyder4), ccxxmake allows a creation of a calibration spectral sample (ccss) for a particular Display, by making use a reference Spectrometer instrument. This can then be used to improve the accuracy of subsequent measurements on that Display using such Colorimeters, by using it with the dispcal, dispread and spotread -X option, or it can be installed, and will then appear in the available display type selection (-y option).

the question is - can an "average Joe" with a regular i1Pro2 device (and not some $xxxxxK lab grade devices covered with "traceable to NIST" stickers) really get .ccss that will improve i1DPro operation (with argyll) vs the regular/generic .ccss files available when you install DispcalGUI, like "RG_Phosphor_Family_25Jul12.ccss", "RGBLEDFamily_07Feb11.ccss", etc

thank you.

Title: Re: i1DPro, i1Pro2, argyll and .ccss calibration spectral samples...
Post by: Czornyj on May 06, 2015, 01:09:49 pm
IMHO - no. i1D3 standard spectral calibrations are pretty decent (done by Konica-Minolta CS-1000), and in more than less cases match the display better than custom .ccss characterisation done by i1Pro2, that has too low optical resolution.
Title: Re: i1DPro, i1Pro2, argyll and .ccss calibration spectral samples...
Post by: AlterEgo on May 06, 2015, 01:21:00 pm
i1D3 standard spectral calibrations are pretty decent (done by Konica-Minolta CS-1000)
you mean exactly those .ccss files that I am talking about from DispcalGUI that in turn were from XRite .edr files supplied with i1DPro OEM software, right ? just to be sure
Title: Re: i1DPro, i1Pro2, argyll and .ccss calibration spectral samples...
Post by: Czornyj on May 06, 2015, 02:19:37 pm
Exactly.
I'm planning to make some test using the JETI Specbos 1211 of my friend to verify my observations, but IMO in case of GBr backlight i1D3 is more reliable than i1Pro2 or i1Pro2 characterised i1D3.
Title: Re: i1DPro, i1Pro2, argyll and .ccss calibration spectral samples...
Post by: AlterEgo on May 06, 2015, 02:27:49 pm
Exactly.
I'm planning to make some test using the JETI Specbos 1211 of my friend to verify my observations, but IMO in case of GBr backlight i1D3 is more reliable than i1Pro2 or i1Pro2 characterised i1D3.

if you happen to do this please by all means share here, thank you...
Title: Re: i1DPro, i1Pro2, argyll and .ccss calibration spectral samples...
Post by: GWGill on May 06, 2015, 11:13:20 pm
IMHO - no. i1D3 standard spectral calibrations are pretty decent (done by Konica-Minolta CS-1000), and in more than less cases match the display better than custom .ccss characterisation done by i1Pro2, that has to low optical resolution.
Right, but a .ccss made with a lesser instrument may well be a great deal better than any other option for non-standard displays.
Title: Re: i1DPro, i1Pro2, argyll and .ccss calibration spectral samples...
Post by: AlterEgo on May 06, 2015, 11:17:33 pm
Right, but a .ccss made with a lesser instrument may well be a great deal better than any other option for non-standard displays.
well, how do you know that you have a non standard display then ? what is the test ?
Title: Re: i1DPro, i1Pro2, argyll and .ccss calibration spectral samples...
Post by: GWGill on May 07, 2015, 09:04:31 am
well, how do you know that you have a non standard display then ? what is the test ?
If you haven't got a reference instrument you feel you can rely on, then it's going to be a subjective judgement. Is the white the color your would expect ?
But I would say that the i1pro and i1d3 have roughly the level of basic accuracy, and certainly if you are intending to measure with a particular i1d3, then you will get a better correction by creating a matrix (.ccmx) rather than creating a spectral reference (.ccss) using the spectrometer.

The advantage of the i1pro is that it will make measurements that are independent of the display technology. The advantage of the i1d3 is that it is faster and more consistent at making low level measurements.