Hi all, I'm wondering if at least for the limited purpose of proof validation/certification, a way to "match" various instruments to a "master" one can be devised. On just a certain paper/ink combo (a single paper, various printers but same inkset - i.e. Epson 3880, 4880 and 7880). I make my iterative proof calibration (Oris ColorTuner) with a DTP-70 ; to a very good match (typical 0.5dE avg, 3.5dE max). But then to check proof stability/validity over time, the customer might use an i1, or even worse, i1-uvcut. From the very first day, if they try validate a proof (typical validation strip 12647-7, 54 patches) it will yield quite different numbers, maybe even out of tolerance. So my plan: 1) in the same style as Idealliance does with their G7 graybalancing target, build some target (large, maybe 8000+ patches) that can be read with all instruments (iSis, i1, DTP-70) 2) print one specimen of that target, linearized/maxgamut on the intended printer/inkset and paper combo. 3) measure that one specimen with all involved instruments (the individual instruments, not the model) - so let's say measure in a handful of i1's, one DTP-70, one iSis, and a few i1-uvcut ones. (output only Lab/XYZ, no spectral needed) 4) make some sort of "Lab-to-Lab" link profile for each instrument to "match" the master one (DTP-70). Then, for proof validation, measure through the individual instrument (ie i1 #2), apply the relevant "instrument correction" profile to the measurements (i1#2 correction), and then use those corrected measurements for a validation that would be closer to the one that would have been made with the "master" instrument (DTP-70). Sounds feasible/useful? (as long as a canned validation software is not used, but just ColorPort or some other measurement software, coupled with an Excel spreadsheet). What should I use to create the "correction link profile" (Lab to Lab) when I have the set of two measurements (master and individual) to be corrected? As long as it's restricted to one paper/inkset combo, will it be useful even to uvcut instruments? -- Roberto Michelena