Hello friends. While I have the Zuiko 75mm 1.8 and is an extraordinary lens, I thought about buying a moderate telephoto for a job for BTS (behind the scene of a movie), where can be I dont need be far away occasionally and with the silent shutter of the GX7 I can be near the set. With the cost of the Panasonic can acquire and the Zuiko 45 and the Zuiko 40-150 (used of course), but in good condition. My question is that there is much difference in quality? the Zuiko 45 is excellent, does the Lumix improvement beyond the better aperture? I advance is not a closed decision, it may not buy it, but I am evaluating the idea. Thanks.