There is no such thing as the best Linux distribution for photographers. With some tweaking, any mainstream distro can be turned into a solid platform for managing and processing photos. After all, digiKam, Darktable, gThumb, and other popular photographic tools can be easily deployed on practically any Linux distribution with a minimum of effort.
The devil is in the detail, though, and small things might require some adjustments. My recent migration from Ubuntu to openSUSE Tumbleweed is a case in point. Most of the tools I use in my photographic workflow are available in openSUSE’s official software repositories, so deploying them was a rather straightforward affair. But there were a few things that needed some tweaking.