[net.astro] eyepiece recommendations

rrm@inuxe.UUCP (Ron Meyer) (07/18/84)

David,

	I have some suggestions for you concerning eyepieces. Although I
don't consider myself an expert at oculars, I know several people who
are and I've used a wide variety of scopes and eyepieces. First of all,
with a rather small f number scope, short focal length eyepieces will not
preform as well on your scope as they will on an f/6 (all other things being
equal). However, you can get good images if you don't ask a lot from your
scope, especially when using a 6mm or shorter focal length ocular. I am
of course assuming that you want to observe the moon and planets, the only
things that really need lots of magnification with little aberations in the
optical system. But to get really excellent images of planets and the moon
you need to get a larger f number objective and use a longer focal length
ocular. Number one point: Short focal length oculars are difficult to make
and do not preform as well as the longer focal lengths. Also the eye relief
is not as great with the short focal length oculars. If I were you, I would
not spend too much on a 12 or 6mm eyepiece. I have Meade orthoscopics (6,12.5,
25mm) and they work very well (note they are not research grade) but my
scope is a homebrew 8" f/6.