It doesn’t happen so often to amateur astronomers to get their hands on a professional-class telescope. But it does happen every once in a while .
On December 27th, 2015, I happened to perform some tests on the Telescope of the “Osservatorio di Fascia” (more info in Italian here and here), located in the Ligurian Apennines (Italy) at 1400 m elevation.
The main scope is an 800 mm f/8 (6400 mm focal length) ASTELCO Ritchey-Chretien, built in 2010-2011. It sits on an alt-az mount and has two Nasmyth foci for visual observation and digital imaging. After my testing session, I took the chance to point this big scope right at the core of M42, the Great Orion Nebula. A few tens of seconds’ worth of exposure was more than enough to capture the faint wisps of one of the most beautiful objects in the entire sky. Imaging camera was a SBIG STL-11000, more details available in the caption. Click on the image below to bring up a full-res version.
M 42 (the Great Orion Nebula)
Before cosmetic cleanup, the original image had some strange patterns in the image, such as the ones shown in the close-up below. Of course they are not part of the nebula, but are most likely due to some internal ghost reflection.