APM - APO SD Triplet Refractor - 180 mm - f/7 to f/5.6 - 4.2" focuser

APM - APO SD Triplet Refractor - 180 mm - f/7 to f/5.6 - 4.2" focuser

This instrument is the entry into the world of really big apo refractors. Ther 180 exactly fills the gap between APM´s 152 mm apo and the 203 mm instrument.
Of course, this telescope requires a really big and heavy mount. Therefore, the instrument is only conditionally suitable for mobile use. For every observatory it is certainly a real eye-catcher.

The 180 mm SD apochromat with the large 4.2 inch R&P focuser allows astrophotography at the highest level. With the 0.8x reducer/flattener, you can achieve a fast focal ratio of f/5.6 with full correction of the image field! This is an optimal prerequisite for full-frame photography. With it, you can easily expose objects all night long. The SD optics enable a colour-pure image, so that even bright stars do not show any colour fringes.

This reducer corrector has an M83x1 male thread on the camera side with a back focus of 55 mm.

The optical elements are crucial for a telescope. But just as important is the mechanically flawless construction of the tube with its internal baffles and suitable focuser. Here APM hase taken special care to use materials with very low thermal expansion. The focuser is tilt-free and carries even heavy loads without any problems. An adequately dimensioned and adjustable dew shield is of course also included. The solid tube rings supplied are CNC-machined and also allow further accessories such as finders, secondary optics (guide scopes, etc.) to be mounted on the side. A carrying handle for the 19 kg instrument is of course also included.

Whether you are interested in solar or planetary photography, visual observations or astrophotography of nebulae, star clusters and galaxies, this telescope will definitely convince you.

Backfocus Info: The refractor has a total backfocus of 250 mm, 85 mm of which is covered by a sliding tube that sits between the end of the tube and the focuser.