It took me a little while to get used to my new system. I can't over from Canon and bought the EM-1 and 50-200. I had trouble at first but have gotten the setting like I want them on my em1 and love it! This lens is sharper than my original Canon 100-400L and equal to the new 100-400l. Plus its a 2.8-3.5 Here are a few shots from today. All of them are pretty big crops. I LOVE this lens. What a jewel. I got it on ebay for $340 with 2 filters in like new condition.