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Stellarvue 102D

Started by jmcarp, 08/07/2003 12:45PM
Posted 08/07/2003 12:45PM Opening Post
A couple of days ago there was a thread under the topic "Pronto vs. TV76 vs. TV85 vs. Sky90 vs.??" in which a question was raised concerning minus violet filtering on the Stellarvue 102D's objective lens. I remember reading a recent post on the Yahoo Stellarvue group in which Vic Maris addressed this issue. I couldn't find the specific message in the group archives, so I e-mailed Vic at Stellarvue for a clarification. His response follows (posted with permission).

Jim

"The prior 102D's had minus violet filtering in the original objective coating. It was not an aftermarket coating with the center uncoated as this was not durable and created diffraction problems. Some aftermarket filters were tested but the extra optical element reduced performance. This may have been due to poor optical quality in the aftermarket filters used. Stellarvue is producing a new 102D without filtering and using a different method to add and eliminate attenuation. These are due to appear around November.

Hope that helps.

Vic"