Am 26.08.2014 19:44, schrieb Roger Breton:
Isn't the "target" illuminant always D50 in an ICC profile?
The virtual illuminant of the PCS is always D50 by definition, but the PCS isn't the color space of your print, but a mathematically defined virtual one. The desired viewing light source for your print can be whatever you want (incandescent lamp, fluorescent lamp, etc.), and the point is to build a profile for the print under the actual viewing light source. If you want to view your print under D50 light, then you are of course free to choose D50 as viewing light source. Print standards are a different story. They define standardized conditions, whose assumptions may or may not match reality. I guess there are more people around who read a magazine under incandescent or fluorescent light, than people reading their magazine in a D50 viewing booth ;-) But admittedly it would not be practical either to sell different variants of the same magazine, each one intended for a different viewing light source. So one needs a compromise, even if it is not perfect, and the standardized compromise is just D50. If you are working in the print business, then you may be forced to comply with standards, regardless whether they are optimal in a particular scenario, or not. Your personal, individual solution is not bound to any standards, though, and you can go the pure scientific way. Btw: The FWA compensation becomes necessary, if the spectrometer's light source does not match the desired viewing light source for which the profile is built. If the spectrometer uses an incandescent lamp for acquiring the readings, and if the desired viewing light source for the print were the same kind of incandescent light as well, then the FWA compensation would not make a difference. Regards, Gerhard
Roger -----Original Message----- From: argyllcms-bounce@xxxxxxxxxxxxx [mailto:argyllcms-bounce@xxxxxxxxxxxxx] On Behalf Of Graeme Gill Sent: 26 ao├╗t 2014 09:22 To: argyllcms@xxxxxxxxxxxxx Subject: [argyllcms] Re: Fwd: Question about M1 measurements Roger Breton wrote:So corrections are "illuminant-dependent" then?Dependent on the target illuminant, yes of course - the whole point is to correct the readings for the target illuminant. Graeme Gill.