The 8-bit vs 16-bit printing debate is way larger than the question I'm asking... Let's just say I shoot 14-bit raw images and process them in 32 bits per channel (bpc), and would like to print (on an Epson P800, up to 17" wide) at the highest quality possible.
I use the Turboprint driver and I am looking for a way to avoid using Gimp for printing, as it only supports 8 bpc (the 2.9 development release supports higher bit depth but is a nightmare to maintain on Archlinux).
For single images I export directly as pdf (16 bpc) from Darktable and print using gtklp, but I need a way to assemble smaller images on a single page and export as a pdf document, to save on paper.
Hence my question about Scribus and 16 bpc images in pdf.