Homemade Newton 200 mm f/6

The telescope mounted on a Gemini G41 mount
This is my first completely homemade telescope! The optics were grounded and polished with my friends Filippo Riccio and Paola Battaglia, and we're proud of the result! It took nearly 6 years from start to first light, maibe too much... but we've decided to take our time and get the maximum result.
Optical testing shows that the primary mirror has a maximum peak to valley error of about 1/10 lambda, that is a maximum error of less than 30 nanometers on the optical surface (equal to about 250 atoms!). The tube assembly is a double truss structure, that can be dismounted so that the whole telescope is collapsed to a box of about 25x25x46 cm, excluding trusses.
The focal length is 1260 mm, very good to be used as an astrograph. I've obtained very good images with a Baader coma corrector and my Canon EOS 5D (24x36 mm sensor), producing point stars all over the field, with only a minor vignetting due to the 2" focuser, easily solvable with a flat field.

Detail of the primary mirror

Detail of the secondary cage

Together with a Pentax 75 refractor

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