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Using focal reducer with the Collapsible Dobsonian for fast imaging?

Equipment Reducer Dobsonian
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Abhijit Juvekar avatar
Abhijit Juvekar avatar
Hi,

I recently thought about using a focal reducer like 0.67X which we use for RC to use with Collapsible Dobsonian (SW 8 inch or 10 inch versions )

We can lower the upper section in order to reach the correct focus after adding the focal reducer and get lower F ratio.

Has anybody tried it?

e.g.
 Flextube 200P Collapsible Dobsonian is 1200mm F5.9 with 0.67X focal reducer we can get it to F3.9 at 804mm FL ?
andrea tasselli avatar
andrea tasselli avatar
Abhijit Juvekar:
Hi,

I recently thought about using a focal reducer like 0.67X which we use for RC to use with Collapsible Dobsonian (SW 8 inch or 10 inch versions )

We can lower the upper section in order to reach the correct focus after adding the focal reducer and get lower F ratio.

Has anybody tried it?

e.g.
 Flextube 200P Collapsible Dobsonian is 1200mm F5.9 with 0.67X focal reducer we can get it to F3.9 at 804mm FL ?

It isn't going to work. You need a reducer-corrector designed for newtonians, of which there are but a few. And expensive.
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