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FCD1 glass from Hoya has the same optical properties as Ohara FPL-51 glass. The abbbe number [how they measure CA] of FCD1 / FPL-51 is 81 while FPL-53 is 95 - almost the same as pure Fluorite. The FPL-53 does get 20 odd percent better CA correction then the FCD1 / FPL-51 [all things being equal]. However a lot depends on the tolerances, machining, quality of build and esp. the mating glass. A poorly made FPL-53 scope will do worse then a well made FCD1 / FPL-51. Don't forget the Meade 5000 80mm is a triplet design which also helps CA correction. Visually you may not notice the difference between a triplet Hoya FCD1 and a Doublet FPL-53 - maybe some more minor spurious colours on bright objects being the difference - with AP it could be more noticeable. The reviews for the Meade 80mm appear to be good.
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