What a great idea Sigma to set these goals based on what is expected of them, using simple software (you have to read everything before you want to change settings of a zoom) in case of "panic" there can always reset "standard norms" in 2 clics.Et if the future of the objectives was that path ??. For my part I tried the shot, so far I am very satisfied with this dock (nikon) .With a little practice, the results are "extras", accelerated development ,, distance framed work, short, with a little practice (sometimes a bit more than expected ..) it's all good.