Orthoscopic eyepiece question

I was browsing around the WWW tonight and encountered the University Optics
site and their Orthoscopic eyepieces. So, what's an Orthoscopic eyepiece
versus Plossl, Radian, Nagler, etc.

Ooooohhhhh nooooo -- I just asked the wrong question - - - here goes the
Great Eyepiece Debate again. Forgive me for I am a novice and I have
sinned.

--

----
Joe S.

Joe S. wrote:
So, what's an Orthoscopic eyepiece versus Plossl, Radian, Nagler, etc

See:
http://www.astronomydaily.com/atm/ep.asp
(you may need to register)

For specific eyepiece specs, see:
http://www.klhess.com/telespec.htm

Best,
Stephen

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On Wed, 23 Jul 2003 21:34:00 -0400, "Joe S."
wrote:

I was browsing around the WWW tonight and encountered the University Optics
site and their Orthoscopic eyepieces. So, what's an Orthoscopic eyepiece
versus Plossl, Radian, Nagler, etc.

Ooooohhhhh nooooo -- I just asked the wrong question - - - here goes the
Great Eyepiece Debate again. Forgive me for I am a novice and I have
sinned.

Performance on planets, the Moon. Also, generally neutral colouration
of those objects relative to some other eyepieces, and affordable,
even in expensive brands like Taks. When you realize ultra wide field
eyepieces serve well for wide field objects, you buy another eyepiece
for ultimate contrast, FOV not being that important.
But, having said that, the new TMB Monocentrics might be worth
comparing, even if they cost nearly as much as Radians.
-Rich

(If you are lucky), you get what you pay for...

"Joe S." wrote in message
I was browsing around the WWW tonight and encountered the University
Optics
site and their Orthoscopic eyepieces. So, what's an Orthoscopic
eyepiece
versus Plossl, Radian, Nagler, etc.
Joe S.

(If you are lucky), you get what you pay for...

Always.
But knowing what we're paying for is another matter.

UO orthos I have used are sharp, affordable, lightweight. The field of view is
_not_ wide field at all. The eye relief is close, in mm, to the focal length.
So the short focal length ones have tight eye relief.

Therefore you are not paying for a wide field, nor a standardized 20mm eye
relief. Just a sharp image.


john

"Joe S." wrote in message ...
I was browsing around the WWW tonight and encountered the University Optics
site and their Orthoscopic eyepieces. So, what's an Orthoscopic eyepiece
versus Plossl, Radian, Nagler, etc.

Ooooohhhhh nooooo -- I just asked the wrong question - - - here goes the
Great Eyepiece Debate again. Forgive me for I am a novice and I have
sinned.

For image sharpness and contrast Orthos virtually can't be beat. On
the other hand, they have the smallest field of view (even smaller
than Plossls) and short eye-relief at high powers. Radians, Naglers
and the like aim towards similar image quality but with superior
eye-relief and a generous field-of-view. If you are on a budget, and
are mostly into planetary viewing Orthos should be sufficient. Some
may want a larger fov for lunar observing though.

wrote in message
...
But, having said that, the new TMB Monocentrics might be worth
comparing, even if they cost nearly as much as Radians.
-Rich

Has anyone had a look through the TMBs yet?

Brian A

On
the other hand, they have the smallest field of view (even smaller
than Plossls) and short eye-relief at high powers.

However, they have slightly longer eye relief than Plossls. Typically, an
Ortho would be used for lunar or planetary observing, and in many cases a wide
field would be a distraction.



Clear, Dark, Steady Skies!
(And considerate neighbors!!!)

Even if you decide that wide field EPs are for you (alt/az mount, strong
interest in DSO’s etc.) Buy one Ortho that will give you about 150x
with your scope.

It will be a useful frame of reference, for evaluating other EPs as well
as atmospheric conditions.

All the best,

Dave Werner

I have a suspicion most eyepieces are pretty darn
comparable on-axis, but I certainly do not know that for sure.


For long focal lengths, you are very right. As the focal length gets shorter,
for instance in Dobs, then certain eyepieces will add small amounts of
spherical aberration. Off-axis, that is another whole ball of wax.

Roland Christen