I had "split" a comment for this objective, mounted my Nikon cameras (D40X and D5100), determined message of the case: obstruct the opening of the figure 22. I told myself that it was not worth it to have a goal that opens to 2.8 if it is for use to 22. I sent an email to GEEK TREND that markets that brand. And the answer came to me a few days later: Yes, you should place the mark on the aperture ring 22 and then change the aperture by the commands of the case. What I'm doing donkey I had returned the day before the lens while it is I who have not been able to use it well. MEA culpa.