Congratulations on the scope, it is a rare and beautiful instrument. Paolo's review is right on, although I will say the slower triplets like the TMB 100/800 give the scope a run for its money. Art said there were 10 of these imported to the US, but it is quite rare to see one listed for sale.
One thing I noticed was that there was very limited backfocus with the scope and that 1.25" diagonals barely reached focus. I spent a long time trying to get 2" eyepieces to focus with my scope. While I cannot guarantee this will work with yours, I will put this here for people who may have these scopes in the future and are able to find an old 2" diagonal for an FSQ. There is no room for a rotating mechanism, so the diagonal stays fixed in position. With an alt az mount it is easy to point the diagonal facing up, but with an eq mount you may need to rotate the tube. There may be a better way to adapt 2" eyepieces but it likely involves replacing the focuser.
Why go through all of this trouble?
You need the following:
PreciseParts: make an adapter from a Tak FS-60C focuser (same as in the FC-100N) to a Genetic Wide T-mount Adapter and put 0 for length (shortest possible). This should be 7.3mm in length
Stellarvue 48mm extension 5mm long:
Takahashi 2” mirror diagonal for FSQ-106 (TSD0001 NOT the newer model) - only available used:
The diagonal has an extension that screws into an M48 opening and allows it to be used in 2” focusers. Unscrew the extension, and replace it with the 5mm ring. Then put the PreciseParts adapter onto the end of the focuser – you will need to unscrew the black plastic ring that connects the 1.25” adapter.
On mine, this allowed me to barely reach focus even with a Nagler 31mm.
(no photos of the adapter)
Edited by Derek Wong, 29 September 2015 - 04:20 AM.