AlphaZentauri Posted November 16, 2021 Posted November 16, 2021 I really love using Affinity Publisher as an alternative for InDesign but I have one major problem with it. I usually export my images as JPEGs from Capture One in AdobeRGB to be more flexible when exporting my publisher documents to PDFs for print or to send them on the web. Unfortunately there seems to be a problem though when exporting the file into a PDF and activating "Convert image colour spaces" into my set ICC Profile (let´s say sRGB in this case) and the file size suddenly skyrockets. If I do not have the setting ticked a 16 page 2560*1440 px per page PDF with many images varies between 36mb with quality 100 JPEG compression and 5 mb with quality 70 JPEG compression. When I tick "Convert to image colour spaces" in order to get an sRGB version for web use the file size changes to 175 mb no matter what jpeg compression is set. The problem only seems to be existant with RGB colour spaces. I did a test with ISO Coated v2 and the file size with 70 JPEG compression is a modest 14mb. No matter what other RGB profile is used file size always stays at 175mb. I also checked the PDF in Acrobat and found 2 major problems. The first problem is that the JPEG compression seems to fail. No matter how I low i put the JPEG quality the resulting images always look the same. The other problem is that the bit depth gets changed. If I export without conversion the photos have 24 bit/pixel. If I tick the conversion option I get 48 bit/pixel which would mean 16 bit per channel. Using CMYK colour spaces the conversion works flawlessly, same for the compression and the images in the files have 32bit/pixel aka 8bit/channel. My other settings are as seen in the attached screenshot. I am using the latest build of Affinity Publisher and Windows 10. I am looking forward to your suggestions and insights! If this truly is a bug I hope the Affinity team will fix it soon Quote
Staff Callum Posted November 19, 2021 Staff Posted November 19, 2021 Hi AlphaZentauri, Welcome to the forums I'm having a lot of trouble replicating this behaviour here at my end. If you try this with a new test project using just one of your images does the same issue occur? If it does would you mind going to File > Save As package and then send me the resulting package file so I can try replicating this issue again? Thanks C Quote Please tag me using @ in your reply so I can be sure to respond ASAP.
AlphaZentauri Posted November 19, 2021 Author Posted November 19, 2021 Hello Callum! Thank you for your answer! I think I have found the cause of the problem now. If the colour format of the document is set to RGB/16 the JPEG compression of RGB colour spaces at export fails. So as soon as the colour format of the .afup is set to RGB/8 the compression works well. I don´t really understand yet, why going from 16bit in file to 8bit JPEGS is a problem for RGB images but not for CMYK though. Because with a CMYK colourspace set as the export colour space the problem does not occur - no matter if RGB/16 or RGB/8 is selected in the document setup. Thank you! O Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.