I use a Schneider 58 mm XL. I only shoot color chromes and always use a centerfilter, even with Astia. I find that I can get good slides without a centerfilter, but using one makes a huge difference in getting a close to perfect exposure (to my eye). I was very concerned about bellows flare when I got my camera. I've looked for it and never seen its symptoms (reduced contrast) in any of the couple thousand slides I've shot. For my 135 mm and 240 mm lens I usually use a lens hood. For my wide angles (75 mm and 58 mm) I don't. The image circles for the wide angle lenses aren't large enough to pose even a remote possibility of bellow flare, in my unscientific opinion.