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Explore Scientific 5" Apo Review

Started by Rod Kaufman, 01/18/2010 01:05AM
Posted 01/18/2010 01:05AM Opening Post
Anybody else catch the review of the explore scientific 5" apo in Astronomy magazine? The author of the review is a dean at a liberal arts/sciences university and he appeared adept at putting the scope through its paces. He felt his most demanding test for chromatic aberration at night was to train the scope on the full moon and then look for the latter at both in-focus and out of focus views and he found none. The performance seemed pretty impressive and the lens is supposed to be a three element job with one or more components being made from Hoya low dispersion glass.
The scope and its mechanicals at f7.5 looked quite nice. Anybody else have any experience with one of these models?
Posted 01/18/2010 01:45AM #1
Rod:

As Roland mentioned not long ago, the moon is not a particularly demanding target in terms of chromatic aberration and it so large that what one often sees is lateral color in the eyepiece. My own personal favorites for exposing chromatic aberration are Venus, Rigel and Sirius. During the day, a phone pole silhouetted against a bright sky seems to bring out the fringing.

jon



Posted 01/18/2010 02:26PM #2
I'm not sure that being a dean of a liberal arts college has much bearing on qualifications to review astronomy equipment. If he was an astronomy professor, that would be a little different.

Most any bright star would have made for a more revealing test than the moon. Nevertheless, the review was interesting. I guess I would want to see how the lens centering holds up over time. Who is going to be the brave one that goes first?
Posted 02/19/2010 08:07PM #3
Best 5" APO was the Meade 127ED the one I owned had almost perfect color correction. On the full moon it showed barely a bit of false color.