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FlorinC
01 Mai 2017 00:17

Colimare Newton catadioptric
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Acesta este telescopul cu pricina:
https://www.amazon.co.uk/Seben-Boss-1400-150-Reflector-Telescope/dp/B00692THU2
Acest "newtonian" are un barlow in focuser ca sa poata ajunge la focala de 1400. Designul se numeste "Bird-Jones" iar primara cred ca este sferica.
Stelele au mereu coma (nu foarte pronuntat...dar exista) si incerc sa ii mai dau telescopului o sansa. Altfel...ATM-ul...il asteapta. Ca nu ma indur sa il vand altora sa ii "procopsesc" pe altii cu el. Nu e groaznic ...dar am instrumente mult mai bune acum si ceva experienta in plus ca atunci cand l-am cumparat si pot sa fac diferenta.
Am gasit asta pe Cloudynights:

"The problem with every commercial Bird-Jones telescope that I have seen is that they are poorly executed designs. The lens in the focuser is not just a Barlow, but also a corrector for the spherical abberation of the primary. The example that I have just doesn't work. The original design was a little more sophisticated than that. A nice history of the design is given here...

https://en.wikipedia.org/wiki/Newtonian_telescope
and
http://www.telescope-optics.net/sub_aperture_corrector.htm#bottom
