Tried to calibrate mine unfortunately Vivitar super glues the focus ring, making it impossible. Would advice to avoid the Vivitar branded one.
here's some shots F3.5 ISO 3,000 and 1/30th
I cannot get mine to focus less than 1.2meters, which is not that bad I guess, but not ideal at all.
IMAGE LINK: https://flic.kr/p/voV5M3









Got some stiff competition though from the looks of things on here!

