Help! I bought a Cassegrain mirror set mounted in a Cave Astrola mirror cell and secondary spider. They are not Cave mirrors I think, the only ID on them is the number C12-2. This is a 12.5" f16 Cassegrain or Dall Kirkham but I can't identify the mirrors any further. Any help appreciated. Jim
Mirror identification
Started by brewtes, 07/05/2018 09:40AM
Posted 07/05/2018 09:40AM
Opening Post
Posted 07/05/2018 10:04AM
#1
Hi. James!
I don't know how convenient this would be for you, but if you can form a good prime-focus axial image using the PM alone, then the configuration would be Classical Cass. On the other hand, if that image is LOADED with spherical aberration... then it would most likely be a Dahl.
There is another possibility... Ritchey... but that seems unlikely, given the probable vintage of the OTA. Tom
I don't know how convenient this would be for you, but if you can form a good prime-focus axial image using the PM alone, then the configuration would be Classical Cass. On the other hand, if that image is LOADED with spherical aberration... then it would most likely be a Dahl.
There is another possibility... Ritchey... but that seems unlikely, given the probable vintage of the OTA. Tom
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Posted 07/05/2018 11:35AM
#2
I'll take a guess and suggest it may be a vintage coulter DK optics set. I believe Cave would have a serial number on his optics whereas Coulter likely did not. I had an observing buddy who had a set from Coulter and he wasn't thrilled with its performance, hard to collimate and a large secondary, here's an old Coulter ad for them:
https://www.google.com/search?q=coulter+optical+catalogue&sa=N&biw=1920&bih=876&tbm=isch&source=iu&ictx=1&fir=XWvfWtszEzBLMM%253A%252C3wxHFeyUKwJejM%252C_&usg=__84zi6_VojfoWYZRdRphfbnjAqi4%3D&ved=0ahUKEwjN9ozpj4fcAhVwHzQIHUoBB1c4ChD1AQhPMAs#imgrc=HS1U3OsCKuGJEM:
https://www.google.com/search?q=coulter+optical+catalogue&sa=N&biw=1920&bih=876&tbm=isch&source=iu&ictx=1&fir=XWvfWtszEzBLMM%253A%252C3wxHFeyUKwJejM%252C_&usg=__84zi6_VojfoWYZRdRphfbnjAqi4%3D&ved=0ahUKEwjN9ozpj4fcAhVwHzQIHUoBB1c4ChD1AQhPMAs#imgrc=HS1U3OsCKuGJEM:
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