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REFRACTOR COMA

Started by lancetakiguchi, 12/15/2002 08:02AM
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Posted 12/15/2002 08:02AM Opening Post
Miles Takiguchi
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Join Date: Nov 2002

Location: Kailua HI, US

Posts: 4

I have a short f 5.5 refractor that is 127mm that is built from Enlarger lens. Is a f stop the only way to combat coma when looking at planets?

Sincerely,

Miles Takiguchi
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Posted 12/21/2002 10:39PM #1
Ron Oehlert
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Join Date: Dec 2002

Location: Great Bend KS, US

Posts: 157

Mayhaps a bit late, But check on the direction of lopsidedness as seen in the out of focus rings. If it is the same on both sides of focus the objective needs collimating. If the bunching flips 180* inside and outside of focus, the lens itself is to blame. Assuming 127mm aperature, this still should be a fine RFT. Ron
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