The below article contains excerpts from The Display Calibration Guide.
What are CCSS / EDR Files?
Colorimeter Calibration Spectral Sample (CCSS) is a file that supported applications can use to tailor colorimeters to displays for more accuracy. They are created with a compatible spectrometer.
ArgyllCMS and HCFR also uses CCSS files to tailor colorimeters to displays – with colorimeters that support such CCSS files. For example, the i1 Display Pro / ColorChecker Display family of devices are calibrated in the factory and this calibration is stored in firmware.
The i1 Display Pro also comes with EDR files (same as a CCSS but in a different file format) that allows it to be tailored to the display technology you want to calibrate. The issue with the EDR set that comes with these colorimeters is that they haven’t been updated for ages and they are not really suitable for wide gamut displays.
How to Create CCSS Files?
HCFR has a function to create a new CCSS. This is done by using only a spectrometer. The function is available from the advanced menu.
When creating a CCSS, HCFR will measure the 3 primary colours and white. The spectral data for these is encoded in a CCSS file that you can save after creation.
You can use the high resolution mode for capturing the CCSS if you are using an i1 Pro 2 or i1 Pro 3 device, which allows it to use the device’s native 3nm resolution for capture as opposed to the default 10nm resolution that the manufacturer’s SDK provides.
You can also create a CCSS with Argyll command line. Please see more on how to do that here: https://www.argyllcms.com/doc/ccxxmake.htm.
HCFR Crash during CCSS File Creation
Please note that some versions of HCFR crash while creating the CCSS. While the file will be written out, it will be unusable in its current state. To use the file, you will need to change the following line…
SPECTRAL_NORM “0.000000”
to …
SPECTRAL_NORM “1.000000”
After this, the CCSS file should load normally in HCFR.
How to Use CCSS Files in HCFR?
To use a CCSS calculated for a particular display type or display model with HCFR, you need to install HCFR (and optionally ArgyllCMS – see more here) and then pop it into the Color folder under C:\Users\YOUR_NAME\ AppData\Roaming\Color
You will need to show hidden files and folders in Windows to be able to access this folder. Then you can use HCFR – or any other application that uses ArgyllCMS – to calibrate the display with your i1 Display Pro / Colorchecker Display / Colormuki
Display / Spyder 4 / Spyder 5 devices. (I believe Spyder X cannot use CCSS files, unfortunately.)
How to Source CCSS Files?
Option 1
You can download user-submitted CCSS files from DisplayCal’s website. It is best to make sure the file is in CCSS format (not CCMX as it is not transferrable) and that the user used either a high-end spectrometer (such as a JETI) or used an i1 Pro device in its 3nm high-resolution mode to create the spectral set. See the link to the database below:
https://colorimetercorrections.displaycal.net
Option 2
You can check the SimpleHomeCinema.com spectral sample collection here. I need to get round to creating more of these. Too many things to do and too little time as they say.
Option 3
An AVS Forum member call SirMaster has created CCSS and EDR files for JVC projectors and is posting them here: https:// nicko88.com/misc/autocal/. We very much appreciate the community service, Sir!
CCSS versus CCMX
Matrix Corrections are 6 numbers (3 for each axis x, y, z) that describe the drift difference for the colours between a good known sensor (usually a spectrometer) and the sensor you want to use.
If you have a spectrometer at hand, creating a CCMX is likely to be more accurate than creating a CCSS. More on CCMX files in another article.
However, when portability is needed – that is the correction will be used on a different display unit or with a different colorimeter unit – then a CCSS is more accurate. A CCMX is not really transferrable between display units or colorimeter units, as it is coded to the exact display (with serial number XYZ) and a particular colorimeter (with serial number XYZ).
I discuss CCMX files in another article. Look out for it on the site.
CCSS File Use in JVC Autocal
JVC Autocal cannot use CCSS files directly, only its XRITE equivalent called an EDR file.
To use an EDR file with Autocal, you need to place it in the Autocal folder next to the Autocal executable, then rename the file to Projector.edr. Autocal will load this file when you select the Spyder sensor option.
For lamp-based projectors, there is only a slight accuracy gain for calibration compared to the stock EDR file loaded in Autocal.
For laser projectors, the accuracy gain can be substantial that EDR file use is encouraged as the second best option after using an actual spectrometer.
Please note that you must use a different EDR file dependent on light source level (high lamp vs low lamp or low vs medium laser). You will also need to use a different one based on filter position (so low lamp no filter vs low lamp filter).
NZ7 CCSS files will work with NZ8 and NZ9 projectors for their no filter position.
If you are using HCFR to validate Autocal results, it is a good idea to use the corresponding CCSS file so that the sensor has the same correction and you are not correcting for CCSS data differences.
Alternative Sensors in JVC Autocal
If you are using one of the DLL hacks to use alternative sensors with JVC Autocal, then those options will have their own ways of loading a CCSS as below:
ArgyllCMS spotread.exe: the spotread.exe syntax allows for loading a CCSS file. See more here.
If you are using the DLL that Omardris developed for AutoCal, then that tool can also load a CCSS. However, the XRITE SDK can only interpret files with a resolution of 1nm, therefore you may need to interpolate files that have more coarse samples or find ones that have a 1nm accuracy.
ColorSpace DLL: You can add your own EDR files to ColourSpace. See here for more.
If you would like to learn more about displays, and display calibration, you can get The Display calibration Guide here.
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