Thread: Are Longer Focal Length Refractors Making a Comeback??
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Old 01-11-2022, 10:02 AM
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anj026
Plyscope

anj026 is offline 		 
Join Date: Oct 2006
Location: Perth
Posts: 532
That chart is a good reference for achromats Don. I don't think it is accurate for fluorite apochromats.

It is possible now to buy a 80mm f10 doublet apo. Also there is a 102mm f11 apo available. There is a niche market for visual observers.
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