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Old February 6th 04, 08:23 PM
Stephen Paul
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Default First Telescope - Epilogue

"Edward Smith" wrote in message
...

9 1/4 SCT.
Teleview 8mm Radian


I'm jealous g. 9.25's have a great reputation for good optics, and the
8mm Radian will make an awesome planet eyepiece at ~294x when the seeing
supports it. Planet and moon viewing aren't affected by light pollution, and
they are easy to find, so you have a great setup to start with for driveway
astronomy.

I would just caution you to take your time and become experienced. Those
first several sessions sometimes leave you wondering if there is something
wrong somewhere. My first several planet observations weren't so great (or
deep sky for that matter), but now that I have observing skill, collimation
skill and the ability to evaluate the atmospheric conditions based on a star
test, I can't believe I ever thought the images were ever anything but great
in those very same telescopes.

One of the issues I have at home is that 200x+ is not always useful
(nevermind 290x). You may find you need other eyepieces for those nights
when 290x is too much magnification. But even if it's not a problem in your
area on most nights, you will still want at least a 25mm Plossl for ~100x,
a half degree true field of view and a 2.5mm exit pupil. When you aren't
looking at the moon or planets, medium to low powers really come into their
own. As for widest possible fields of view, the F6.3 R/C is one way to go,
and a 2" diagonal with 2" eyepieces is another. Something like the 2" TV
50mm Plossl will get you all the way down to 47x and 1 degree of field
without the R/C, but I'm not sure about vignetting. I "think" the 9.25 has a
large enough primary baffle to allow the maximum field stop in a 2" eyepiece
to be used, but someone might correct me.

Anyway, great choice and best wishes,
Stephen Paul