I did do a test with a Mutoh (flatbed adapted) printer and Topaz RIP which prints onto glass with special inks [it’s a weird fish, that RIP, lots of the manual is about how the manufacturer's "by eye" method is better than using ICC profiles].
Oh god, don’t get me started. I have a competitor nearby that similarly claims his calibration "by feel" is better than anyone’s measurement based calibration, lol.
In this case, the regular process is to print direct onto the back of the glass then paint over the ink with white. The final piece is viewed through the glass - so as a reflective object, not a trans.
I get it - that’s pretty common. I’ve seen people actually use this type of print as “transflective” - both as a reflective print during the day and transmissively at night.
We did try a test of painting the glass white first then printing onto that white surface, with the idea to read the inks direct (not through the glass). Unfortunately, in this case, the appearance of ink on paint is quite significantly different to ink printed direct onto glass.
That feels like a red flag right there. We’re talking about UV Curable inks right? Not Solvent or something else? Perhaps I misunderstood.
Another thought was to have inks on the front surface (to be read direct with the spectro) and white paint on the back but that looks weird so I'm pretty sure it’s a fail.
That should be exactly the same as printing with the same ink order on the back side of the glass, right?
I am planning to try opaque white glass, just for the profile making - in the hope that the inks will take to that glass well and we can "see" the same as we’d see in the "normal backpainted white process". i.e. inks printed straight onto glass - with white backing.
Right, or calibrate and profile on Sintra and use that setup on other materials. I’m starting to get the feeling that you’re not using UV Curable inks for this… From my experience, if you want to print on glass you’ve got to drop everything and go UV curable. Tell us more about these ‘special inks’. p.s. I was just nearby you in Swansea Wales a few weeks ago - gorgeous! Scott Martin www.on-sight.com