[Astromelb]

Dear Morton,

I understand your questions.

This is a twin doublet design, so there are two sets of doublets, making it a quadruplet. Same design concept as the SharpStar 100Q model and Tak's FSQ's.

I agree it is interesting that they both do a 60mm and a 65mm quadruplet, as you state there isn't a lot of difference between a 60mm and a 65mm as you point out.

There is significant volume for SharpStar in both 60mm and 65mm sizes, as customers want both options.

I have the 60mm underway with supply from the manufacturer currently, the 65mm is awaiting a new batch being produced shortly.

These telescopes are very nice as you point out. The designs are deliberate to offer another triplet & quadruplet refractors series to customers here in Australia. All using premium O'Hara FPL53 ED Glass at a very competitive price.

I have taken on the SharpStar distributorship deliberately as people keep asking me for an alternative to other triplets and quadruplets.

Clear skies.

Rgds,
Cris.

PLEASE REFER TO CORRECTION ABOVE AS I HAVE UPDATE FROM THE MANUFACTURER