175mm APO (TMB-design), f=1400mm, APM-telescopes

Wonderful and rare instrument! According to an avid astronomer who observed with it: “The 175mm APM-refractor was of exceptional quality!”.

Comes with heavy-duty tube-ring and an amazing lot of screw-on extension rings (as you can see on the images). The focuser has a (self-made?-) motofocus, with a Robofocus (model 3.1). The focuser needs a bit of cleaning and maintenance after staying for 15 years in the observatory, but the optics are OK (dust-cover and end-caps protected the inside and outside).