Hi all! I'm trying to figure out what my actual FOV is with my Olympus E-PL3, using a Canon FD 135mm prime lens. I'm going to be using this for astrophotography, so knowing the field of view as precisely as possible will help me plan my photos. An online lens calculator seemed to indicate the effective field of view would be ~9.15 degrees, and some image details on Astrobin seem to agree, indicating a diameter of about 9.4°. My own calculations seemed to indicate something closer to 12°, but I could easily be misunderstanding one or more factors that should figure into that number. I'd like to a) get the FOV calculated right and b) understand the math behind it better. Can anyone give me a better sense of what FOV my 135mm lens should be giving me? Thanks!