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I’m planning to calibrate a display that’s connected to an iMac, but I may need to do the actual calibration with a PC. So I’m planning to connect the display in question to the PC and calibrate it, targeting rec.709 gamma 2.4.
Are there any obvious drawbacks if I do it this way and simply copy and paste the ICC profile from the PC to the iMac?
I have a similar question. ASUS monitor used with 2 Win10 laptops, only one of which can run a complete calibration (due to USB3 issues with Huey, I think). DisplayCal is installed on both machines. What I am not sure about is where exactly to put the profile file so that DisplayCal will automatically load it.
Just copy the profile over to the other machine and install it (in DisplayCAL menu File -> Install display device profile…, or right click profile in Explorer -> install, then use the profile loader to assign it to the display).
Thank you, Florian. Sorry for the dumb question.
Now I have a not-so-dumb one: how can I get reference images of the IT8 test charts, for example as tiff files, with RGB values that perfectly match an embedded profile according to the standard? It seems these are not widely available, perhaps because the people who can generate them are in the business of selling test charts. I don’t want to enter any such business, just to better understand my own color management by comparing the results of applying various profiles to the reference images.
Characterization charts (transmissive “scanner” targets, or reflective “camera” targets) need to be measured individually. This requires some relatively expensive gear (transmissive or reflective spectrometer), and also quite some sophistication, especially if one wants to manufacture such charts to tight tolerances (otherwise they would be less suitable for characterization). The device values (e.g. RGB or CMYK) are only used during chart manufacture. To make use of such a chart for characterization, the device values are not needed and thus irrelevant: You only need the physical chart itself, and the measured CIE values for each patch.
I fear you misunderstand. I don’t want the values for any device specific chart, but rather the ideal values from which those might be calculated. Surely such an image can exist independent of any device.
I don’t want the values for any device specific chart, but rather the ideal values from which those might be calculated
If we are talking IT8.7/1 and /2, then there is no such thing.
I’m not sure if you are clear how such targets are used. In case of IT8.7/1 and /2, you scan/photograph a physical (transmissive or reflective) target. The target is accompanied by reference CIE values which are used to create a profile for the respective input device. Using the profile, the reference values can then be reproduced accurately, which extends to similar film/stock being scanned/photographed now also being reproduced accurately (within limitations inherent to the process).
IT8.7/3, /4 and /5 are meant for print characterization. These charts are comprised of several patches with device values (eg. RGB or CMYK) where the device values are spaced in a regular grid (not talking layout here, but the actual device values). Knowing the specification, such charts are trivial to create. But to use them, you have to print them and measure the printed chart with a spectrometer. These measurements can then be used to create a profile characterizing the print.
