I just got my moon shots back, and they are all blurry. I was using a Sigma 400mm f/5.6 mirrored lens. The blurriness happened using both 100 and 400 ISO film, at exposures of 4 to 8 seconds. Should I simply have exposed for a more brief period of time, or is this a consequence of using a mirrored lens?
My shots of Mars had donuts around them, but I knew about the donut problem... Thanks, Amita

