I've picked up a Schnieder G Claron 270 Wide Angle f 11. Barrel lens in mint condition, takes a 110mm filter. Anyone have any info? Image circle? Possible shutter size? Approx. value? External screwthreads on back of lens 85mm, are they for rear filters? Too big for my 5x7 Korona. Looking to go ulf will this get me above 8x10? Thanks for any help.... Bill