[Kunama]

Not much info out there Lewis, you might be able to get some from Markus Ludes at APM he had them 12 years ago. Markus posted that he thought they were optically the equal or better than the FSQ.
"
I have the first imported 108 DED in stock. The lens design is an petzval
like the Tele Vue 101. The DED use an full size ED Douplet in front and an
big douplet ED in the giant 4" Focuser.
Backfocuse is rather small.

The scope is designed like FSQ and Pentax 100SDUHF as an astrograph

Optical quality in my unit is rather good , superior to any pentax I saw so
far and superior to any FSQ i saw so far.

Colorcorrection is similar to the 4"F/9 douplet Vixen ED.

If you are looking for the best 6x7 astrograph, than the Vixen 108 DED is
the way to go . If you are looking for pur visual scopes, than you would go
with something else

best wishes

Markus "