I have a 16bit CMYK file at 600dpi that is 1.713Gb in size. When I try to save it as a pdf it comes back as over the 2Gb limit. I get that it may add a few MBs in the process, however, when I reduce it to 8 bit and the file size reduces to 548Mb, I STILL can't save as a pdf because for some reason it still has it as going over the 2Gb limit. I've closed and reopened Photoshop and also rebooted the machine entirely in case some residual memory thing might be happening.
Any suggestions as to what might be the cause/a solution would be much appreciated.