Now I use it on crop as a staffer. I have been looking for a high-quality sharp staffer for a long time and by trial and error settled on this. Previously tried on tamron 17-50 2.8 (bought and sold) and canon 17-55 2.8 (tested). This one is better. Advice to everyone who is looking for a crop staffer - take 17-40 L, because. in any case, you will come to it, do not spend money on cheaper analogues, because. well, they don’t give a stable, clear picture like an elka (L), anyway, then sell it (like me, having lost money) and buy yourself an L. In general, you can get to know the lens better - rent it, there are different companies that provide such a service for reasonable money.