Posted 11 August 2010 - 03:08 PM
I have two, one a bit sharper than the other. The less sharp one was used on two eclipse trips, and produced very nice pictures. Even shooting the diamond ring there was no evidence of internal reflections, unlike a Canon 300mm f/4 L lens I used for a third eclipse, which showed lots of internal reflections from the multiple lens groups. I thought the focal length was ideal in that I was able to get good detail on limb features like prominences and the chromosphere, and still have enough field of view to capture an extensive corona. All this was on 35mm slide film. I would definitely recommend it for eclipses, but you might want to try it on the moon and terrestrial targets with your camera and decide for yourself.