Re: [gentoo-user] CMYK comparison to sRGB between platforms

[Peter Humphrey <peter@prh.myzen.co.uk>]

On Wednesday 09 September 2015 14:41:19 Mick wrote:

> Would you mind explaining how it works?  You measure the icc of a monitor -
> what do you do with this then?  Do you need to be running something like
> colord all the time to feed some correction data to xranrd?

You get a live DVD (Fedora) with the calibration program and some user notes. 
The device comes with a strap to hold it against the middle of the screen, and 
a 6' USB lead. The measuring process is straightforward, though complicated 
for me by the fact that my screen is LED, not LCD. Still, I told it to treat 
it as an LCD and the result, though a bit bright for my eyes, appears accurate 
enough. It also knows about CRTs and projectors.

Once the calibration is complete (about 10 minutes for the standard 
calibration) you have to copy the .icc directory from ~/.local/share to a USB 
stick or something, then reboot into your usual system and double-click on the 
file in your GUI file manager. That transfers the data to the monitor, 
apparently permanently.

Simple, once you get out of the habit of using the CLI. Well, it would be, 
except that I had to run:

$ Find / -iname \*.icc 2> /dev/null
$ mv .local/share/icc .

Then I could see the icc folder in the file manager and drag it to the USB 
stick.

As for double monitors, the calibration program on the DVD asks you to choose 
the monitor to calibrate, so it can detect more than one at a time, but I 
don't know how transferring the .icc in the main system would work with two 
monitors. You might have to download and install the client tools.

HTH.

-- 
Rgds
Peter