Among all the instruments I enumerated, the PR-704 can be a reference instrument ? no offence / Roger From: argyllcms-bounce@xxxxxxxxxxxxx [mailto:argyllcms-bounce@xxxxxxxxxxxxx] On Behalf Of János, Tóth F. Sent: 1 octobre 2010 21:02 To: argyllcms@xxxxxxxxxxxxx Subject: [argyllcms] Re: ColorMunki measurement drift Well, I think we should compare each of those instruments to a much better reference instrument (or a reference light source), but not between each others. I think it can't tell anything. They will be closer to or further from the true but randomly, so you can't tell.