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would you say this is a good deal? 12.5 dob truss
http://www.astromart.com/classifieds...fied_id=325218
I'm considering purchasing this home made truss. Sellers ratings are good and from other post i've read astromart is a good place to buy. I don't really know what to ask the seller. Help! I'm limited to some catadioptric and truss designs do to the fact I can only get items shipped via USPS. (Overseas U.S.A.F.) Thanks all DH |
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Impact9 wrote:
http://www.astromart.com/classifieds...fied_id=325218 I'm considering purchasing this home made truss. Sellers ratings are good and from other post i've read astromart is a good place to buy. I don't really know what to ask the seller. Help! I'm limited to some catadioptric and truss designs do to the fact I can only get items shipped via USPS. (Overseas U.S.A.F.) Thanks all DH Ask him more about the mirror figure. Ask him to fax you an interferometry report. Everything else on the scope is low-ball, imho. It's cheap, but we don't have any idea how good the optics are, or if it moves well. I don't like the truss tubes. An f/4 scope is going to be very sensitive to collimation, so either you're going to have to re-collimate on every assembly, or do something with the truss tubes to ensure repeatable re-assembly. Are those conduit clamps he's using at the mirror box? Ugh! The back of the mirror box is closed. It will take this scope a long while to cool. So imho, the value of the telescope structure is slightly more than zero. The value of the optics are variable, depending on how good they are. If the optics are good (and you can determine this with a foucalt tester, ronchi or interferometry test), it might be worthwhile. It appears to be a very unremarkable home-made scope on the surface. I'd pass unless I could look through it before writing the check. That's my *opinion*. Good Luck! Uncle Bob |
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