My second serious attempt at a long exposure deep sky image with this lens (the first is
here) - the Russian LZOS Rubinar 500mm f8 mirror lens.
This is a HDR composition with a Canon 400D at ISO800:
21 x 30secs subs
15 x 120sec subs
16 x 240sec subs
11 x 600sec subs
Ambient temps of about 28C. Processed in PixInsight (which I'm still learning). Any advice on how to deal with the halo/reflection thingys appreciated. Otherwise I think this lens shows quite a bit of promise as a low-cost & light-weight flat field APO alternative.
Larger image here:
http://www.astrobin.com/31981/
Thanks for looking