Best tool yet for helping visualize a shot – Lens•Lab Review

Freaking love this app. In 30 seconds it taught me what two years shooting hadn't ... that shooting a long lens wide open means your depth of field is about 3 inches. Sliders and a visual index that gives you an idea of the relative size of things as they'll appear in frame make this the best lens tool I've run across yet. Great for anyone shooting rangefinders as well.
Review by webslog on Lens•Lab.