This is an exceptionally stylish and unique model! I did not resist its charm myself - I recently finished refurbishing probably the same model, from a slightly earlier period (it has engraved markings instead of a sticker which probably indicates 1958 or earlier). It's great that you managed to keep this first scope in good condition to this day. Are you sure about the 900mm focal length? Maybe it is counted together with the Barlow lens built into the adapter? In my copy the lens has approx. 450 mm focal length ...
Towa 60/900 restoration thread
Posted 03 May 2021 - 11:23 AM
Your sample looks brand new. Amazing you were able to restore it in this condition, considering it's age.
Do the engraved markings say Towa?
Have to check for the built-in adapter, last time I had it out I remember being able to see the SL9 Comet "spots" on Jupiter.
I noticed your focuser looks like it screws on the back of the OTA, mine has the 3 screw configuration.
The focuser knobs are different but the tripod looks similar .
These were probably designed mainly for Terrestrial use, I really like the rotary 3 eyepiece holder.
Posted 03 May 2021 - 11:55 AM
Thanks, it actually looks a bit worse than in the pictures. Not very well thought-out design of the "mount" causes the tendency to uncontrolled falling of the tube, which is why it is battered from the bottom. The eyepiece adapter is cracked and it would have to be dismantled to stick it. However, I am afraid that the old, polymerized material will not be able to withstand unscrewing the side covers.
The focuser is engraved with the "Circle T" badge and is branded as "Marine". I believe Marine is a Towa brand used to label "spotting scopes" category instrtuments in the 50s or even later. You're right - in my model the focuser is simply screwed into the tube. The knobs in my copy are a typical 1950s Towa design that was later abandoned.
When it comes to the eyepiece adapter, personally I have mixed feelings - the permanently built-in Barlow lens never bodes well, here we have an additional second lens erecting the image. I think that when it comes to the main lens it is of quite good quality, but these additional lenses deteriorate the image a bit - although its quality is close to the standard of later Japanese "spotting scopes" equipped with a zoom.
It is a pity, however, that you cannot miss those additional elements that are needed to reach the focal point hidden inside the tube - then we would probably have a really good, "fast" refractor for wider fields ...
Some time ago I devoted a separate thread to my adventures with this model: https://www.cloudyni...piece-revolver/
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