View Single Post
Old 02-02-2012, 01:13 PM
clive milne
Registered User

clive milne is offline
Join Date: May 2011
Location: Freo WA
Posts: 1,443
A rough sagitta calculation indicates that the central thickness of a 25" f4.2 made from 19mm float will be around 10mm, and a bit over 12mm for the 22's...

Reply With Quote