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Old 30-10-2012, 12:01 AM
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cometcatcher (Kevin)
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Join Date: Jan 2005
Location: Cloudy Mackay
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Quote:
Originally Posted by arifmshaikh View Post
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.
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