Isnt there an issue uploading 16 bits photos to GIMP - or is that issue solved?
I've not been aware of any issues loading 16 bit depth images in GIMP in recent years. What issue are you referring to specifically?
As to the Ubuntu/TurpoPrint etc issue - yeah, that's the kind of thing that made me drop out of Ubuntu some years ago. There would be an update and this would break random stuff, and I'd have to spend hours trying to fix it. I got tired of it and went back to Windows for my desktop environment.
am I able to control what color profile the printer is using from Ubuntu?
The thing is that in
@gary mulder 's suggested setup, the printer manages its own profile. You just send srgb to the printer. The printer then handles the rest. I'm not sure whether your printer supports this.
The classic/old-fashioned way is to have the printing application manage the printer's colors by attaching a custom profile. Shotwell AFAIK does not have color management capability. IDK about ImageViewer, but given its primary purpose, I don't expect it's geared to this end.
As to having Ubuntu managing printing profiles directly and then hoping that nothing will get lost in translation between the app you use to print from and the actual printer, I'm not sure, but info like this doesn't make me enthusiastic:
https://askubuntu.com/questions/668345/printer-color-management-how-do-i-calibrate-my-printer See also here:
https://discuss.pixls.us/t/gutenprint-linux-assigning-icc-profile-for-printer-paper-combo/23876/5 Seems like you'll have to construct custom profiles for your printer & ink & paper &
and the printer driver you're using on Ubuntu. In other words, it's apparently 'normal' that ICC profiles supplied by vendors intended for use on e.g. Windows or Mac platforms will not work with open-source drivers.