GREAT JOB BY SIGMA. YOU MAY NEED A HEAVY DUDY TRIPOD FOR VIDEO CAMERAS. I GOT ONE FROM MANFROTTO ABOUT $400. IF COMPARED TO NIKON AND CANON 600MM LENSES, THIS QUALITY IS SAME AT A REASONABLE PRICE. I PURCHASED FROM SIGMA4LESS FOR A GOOD PRICE. BE CAREFUL!
PERFECT AUTOFOCUS GOOD PRICE
IT IS 6KG HEAVY