Thanks Asher! Well, it was taken with a selfmade contraption (focusing helicoid mount with taped in lens, no aperture) consisting of an uncoated quartz singlet lens. It was shot at full aperture (geometrically f1.0 actually) on a digital SLR camera. That lens element I found long time ago in a optical surplus store when I was searching for UV capable lenses. That idea was influenced a bit by the design of the Struss Pictorial Lens and the Hanovia Kalosat quartz lens, both hard to locate today. I am used to build such solutions with the help of my mechanic and as this turned out to deliver good results, will be turned into a mechanically well made solution (tape is just for testing, not for later use...)
That image is just resized and otherwise completely unaltered according to my puristic shooting approach.