Just want to say, after years of using PhotoShop, I was unable to afford upgrade subscriptions when I moved to MACOS High Sierra. Affinity Photo is a tremendous alternative. I recently had this PDF Export problem. A printer I have worked with for years to do postcards told me my PDF Export of a design in Affinity Photo was only 72 DPI. I had set the doc up as a 4x6 postcard with bleed (4.25 inches by 6.25 inches), and choose the default profile for CYMK instead of RGB color. My design contained 3 images. Two of those were video screen captures and were 72 DPI PNGs, while the other was a 400 DPI photo. All the images were reduced more than 50% from their imported sizes, so I thought the PNGs would still get by. The other layers contained limited text and a solid background color. When I exported I chose the PDF (for print) at 300 DPI, using the Bilinear default. I was confused by the Printer's rejection of the PDF, since this is more or less the same way I used to set up PhotoShop docs, and I had used lower res images in the past without the entire PDF being rejected as 72 DPI. I read some info from Affinity regarding "Upsampling" and info about the Bicubic export choice. I then went to Doc Setup and did an Upsample at 300 DPI, which didn't appear to take any time or change anything - because it was already 300 DPI(?) Then I exported the PDF (for print) at 400 DPI and chose Bicubic option, no rasterizing. In the resulting PDF, the PNG images looked a tiny bit clearer on my monitor, but I wasn't sure about printing. Printer said the updated files were good and ran the job (which I haven't received yet). Although what I did worked, it was a shot in the dark. I'm interested to know why this Export to PDF was more involved than what I used to do in PhotoShop.
