Transcendent RFV(Real Field of View) has come true on the APM120-90deg Binocular.
By the surprising change of the view point, I have scceeded in taking full advantage
of the rich field of MASUYAMA-32mm-85-deg. with the minimum sacrifice of the listed FOV of 85-deg.
About 3.6-deg of RFV seems to be secured by my visual estimation.
After a lot of twist and turns in my mind, I finally decided it is the best way to attach and remove the Binocular from the horizontal unit.
As the original horizontal drum would not accept the encoder, I had to replace it for my horizontal unit with encoder. I firstly planned to replace the horizontal shaft for a dovetail so that the Binocular can be released from the horizontal unit by the dovetail-holder. But I found it more wise to use the original horizontal drum as a extension pillar. Inserting the shaft into the drum hole is easier than set the dovetail into the holder.
But I found the clamp screw could not perfectly lock the shaft from slipping, and I made a boss and a hole on the top of the drum and the base plate of the arm mount.