Created attachment 136337 [details] example slides A vector graphic (like eps) used as a background image is rendered in poor quality when viewed in slide show mode. Interestingly, the rendering is well done when adding the eps-image as an image object. Additionally, when the odp-file is exported to pdf, then the image is rendered well. The behavior seems to be already reported at https://ask.libreoffice.org/en/question/46375/image-quality-higher-in-exported-pdfs-than-odp-how-to-get-best-quality-images-in-odp-presentations/ The attached odp file contains two slides: the first uses an eps-file as background image, the second displays an image object that is the imported eps-file.
Thanks for reporting this issue. It seems to me like a duplicate of bug 87450 *** This bug has been marked as a duplicate of bug 87450 ***