Hi! thought I’d try my own tests:
tripod with IS to off, mirror-lockup, remote release. I took five shots with each combination, refocusing each time, then manually selected the one that looked best.
This is on the Canon 60d with the 70-200mm 2.8 IS II at 100mm, iso 100, 1/320 sec, f5.6
The three tests are: bare lens, 77mm 75$ hoya filter, 77mm 116$ b&h uv filter (http://www.amazon.ca/77mm-Clear-Haze-Multi-Resistant-Coating/dp/B0000BZLBQ/ref=sr_1_1?ie=UTF8&qid=1426763205&sr=8-1&keywords=B%2BW+77mm+Clear+UV+Haze+with+Multi-Resistant+Coating+%28010M%29)
Wanna guess which is which? 😉