Using 500mm lens for astrophotography

arifmshaikh · #1 29-10-2012, 10:33 PM

I have 170-500mm apo lens which I am thinking to use for wide field astro photography. I see that refractor needs field flattner. Do I also need ff with this lens. What are the pros and cons of using this lens vs refractor telescope.

cometcatcher (Kevin) · #2 30-10-2012, 12:01 AM

Quote:

Originally Posted by arifmshaikh

I have 170-500mm apo lens which I am thinking to use for wide field astro photography. I see that refractor needs field flattner. Do I also need ff with this lens. What are the pros and cons of using this lens vs refractor telescope.

No you won't need a field flattener. Should make a reasonable lens for AP.