Astro Photography
I am both fascinated as well as frustrated by astro photography.
Fascinated because it opens the eye for the universe with all its wonders and stunning beauty.
Frustrated because I know from experience how much longer and bigger the lenses of the pros (aka astro physicists) are. But it is more fascinating than it is frustrating ;)
Whoever wonders, my gear is a Vixen Sphinx SXW computerized equatorial mount and a Celestron C8 eight inch Schmidt-Cassegrain carbon optical tube assembly with Celestron f/6.3 reducer aka field flattener (makes the telescope a 1260 mm f/6.3 reflex lens).