BORG 107FL Visual Sets

I just prepared for two kinds of Series 115mm visual observing sets. Biggest advantage over Series 80 is the larger focuser’s drawtube allows to avoid vignetting even when long light path accessories such as erecting mirror diagonals and Binoviewers etc are used.


With BinoTechno erecting mirror diagonal and Masuyama 26mm

So far, BORG 107FL and Masuyama 26mm was the best combination for the wide field of view in my experience. 32mm wasn’t unfortunately.

BinoTechno 2″ EZM requires almost 150mm extra back focus. Generally 30mm longer than conventional 2″ diagonal(?). The focuser drawtube position in above picture shows it’s in focus at the infinity.

These two packages have been added in Hutech E-store. Major differences between these two packages are the focus travel and with an extension tube (7603) or without.


Main tube – 8240 is same length as F3.9 configuration. So it’s quite easy to convert F3.9 to visual or prime focus setup.

~ by tedishikawa on March 9, 2020.

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