OK. We're talking the same language and getting closer. Thanks for the clarifications of terminology
When I produce a slideshow with H.264 AVC, add a menu and then burn the result to a DVD in PD18, I put that disc in my Blu-Ray player to watch it. The resulting menu is functional and the menu image is fine. My problem is with the slideshow images that follow; they are visibly poor. They are significantly worse than the slideshow images on the disc I created by burning a DVD with the software on my PC rather than using the burn function in PD18. (But doing it that way leaves out the menu.)
I assume that simply adding a functional menu to my produced file does not, by itself, degrade the slideshow images. That leaves only the burning process in PD18 as the likely culprit.
For now, I've elected to burn the best possible slideshow images, meaning I'm using the software in my PC and putting up with the lack of a menu. There must be a way to get the menu AND get the good slideshow images. If you've got any more suggestions, I'd be glad to listen.
Thanks for taking time to reply.