Bokeh can be beautiful. It can also be crazy. Especially when using the Minolta MD Rokkor-X 500mm mirror lens.
Because the lens is not refractive it requires a careful choice of background to avoid doughnut bokeh. Catadioptric lenses use two mirrors. The secondary mirror partially blocks the main mirror blocking out the center of each light disc which in turn produces the characteristic doughnut bokeh. I actually don’t mind the doughnuts in certain situations. They can be artful. But they can also be insanely busy and ruin your carefully crafted photo composition. So how to avoid those doughnuts?
Try to shoot with backgrounds that have even tone and little in the way of finely textured features. Things like grass, trees in full leaf, glittering light, features with high contrast — all will result in doughnut bokeh.
This shot I took of a red-bellied turtle shows what happens when the background is too busy. Totally bonkers bokeh that distracts from what should be a really nice shot.
On the other hand this shot of a Slaty Skimmer dragonfly was shot against the surface of the pond. As a general rule, single toned sky, large structures of even tone, water without heavy light reflections will smooth out and give that desired creamy effect.