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Jaegers 6" F8 delivers on Saturn, not Jupiter

Started by Bill in Ballard, 12/25/2003 01:40AM
Posted 12/25/2003 01:40AM Opening Post
Last Sunday we had clear skies in Seattle so I pulled out the old Jaegers, and with a 9mm Nagler, Cassini's division was absolutely clear, and there was some shading on the planet.
Thrilled by Sunday's success, I thought I would try an early morning session with Jupiter. At 0500 Jupiter was high in a clear, southern sky. At first look with a 32mm U.O., and a minus violet filter there were two bands and the four Gallilean Moons (a good start I thought). However,any attempt to increase power resulted in a washed out lifeless orb. The viewing conditions were not the issue. It was the dreaded chromatic aberration. The minus violet filter didn't even put a dent in it.
I have been thinking long and hard about a chromacor, but I have been on the fence because of expense, and I'm not sure how easy they are to use with different eyepieces. Has anyone had good results using a variable polarizing filter on planets? My goals are to see detail on the surface of Saturn and in the rings...I would also like to be able resolve the red spot and more than two bands on Jupiter. If the only way to get that type of performance out of a fast achormat would be with a chromacor then it would unquestionably be worth the price but if a polarizing filter would do it, then that would be even better.
Posted 12/25/2003 04:04AM #1
Hi Bill,

Try this link. One of the moderators is a man named Sol Robbins, he is a real whiz on the subject of the Chromacor. The success people describe with 6" f8 Syntas should give you something to really think about. The designer of the Chromacor is readying the launch of the Chromacor III that he says will be a true plug and play device.
http://groups.yahoo.com/group/Chinese_Refractor/

Happy Holidays,

Steve
Posted 12/25/2003 10:22AM #2
I've not tried a polarizer, but just on theory I
would not expect it to help much.

There is no difficulty using Chromacor with different
eyepieces. Maybe if you tried something like a
50mm or 60mm Plossl the edges of the field might
be dark or cut off.

It does take some effort to find one matched
to the spherical aberration (and to lesser extent,
color correction) of your scope. Might also
need to make sure the focusser is squared-on
the optical axis, and maybe collimate the main
lens. But result is well worth the efforts.