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Spotting scopes and Astronomy eyepieces (1 Viewer)

A

AlbertoJ

Well-known member
I know Zeiss scopes have astro adapters and can use 1/4" and 2" astronomy eyepieces (like Nagler or Pentax XW).
Swarovski has 1/4" astro adapter.

Which other Spotting scopes can use astronomy eyepieces?
 
Celestron and Pentax. Focus travel is limited in any fieldscope so not all astro eyepieces can reach focus at infinity.

Rick
 
Also the Optolyth has astro adaptors.
The Kowa 88 can also receive astro-eyepieces but you have to do the adaptor as already shown in this forum.
Having a Nikon FSA-L2 I guess that the Nikon EDG can also receive astro-eyepieces and reach focus. The easiest way of doing that would be to "adapt" the Nikon adaptor to use the previous Nikon eyepieces on the EDG. I would do a T hole on it and would use a adaptor of T to 1.25"...

David
 
Thanks for reply.
I´d preffer haven´t to do any adaptor if I can avoid it.
Ok, I think my choice is reduced to Zeiss, Swarovski and Pentax.
 
Alberto,
If you use a Baader adapter for Zeiss there won't be any difference comparing with a change of Zeiss eyepieces.
The big Kowa at 100X must be a crack.
By the way, are here any user of 2" astro eyepieces in a spotting scope?

Fernando
 
BobinKy said:
Is there a formula to calculate this problem?

...Bob
Click to expand...

It's more a mechanical issue of where people place the focus compared to the seat of the EP. The focuser can take up a it of slack but not all of it. There isn't a standard mostly because the astro people all have long travel focusers and are only interested in focusing at infinity.

When folks designer spotter EPs they all have a well defined seating plane and they make sure the focus of the EP matched the focus of the objective.
 
Fernando np said:
By the way, are here any user of 2" astro eyepieces in a spotting scope
Click to expand...

AFAIK there are no spotting scopes whose bayonet or screw mounts could accept a 2" eyepiece.
An adapter would place the eyepiece so far awayfrom the scope body that focussing to infinity would be impossible.

John
 
And no point since the prism clear aperture is never more than 20~25mm. Much smaller than the 27mm fieldstop of the widest 1.25" eyepiece, the 24mm Panoptic.

Rick
 
John Russell said:
...AFAIK there are no spotting scopes whose bayonet or screw mounts could accept a 2" eyepiece.
Click to expand...

If one looks outside the prism design spotters, to the small APO refractors (by Televue, Stellarvue, Astro-Tech, etc.) can take 2" eyepieces. All have 2" diagonals , and some of the companies sell an "erecting prism" for 2" occulars, that makes the orientation of the view similar to that of the prismatic scopes. Their are also quite a few 3rd party diagonal/erecting prism options available also.

Of course, the small refractors are not waterproof, as the Macsutovs are not either.

Also, a 2" eyepiece/occular is normally in long focal lengths, which means usually a wider field but low power views.

For example let us assume a 20mm 2" occular with a 600mm focal length scope. That would be 30x.
 
"For example let us assume a 20mm 2" occular with a 600mm focal length scope. That would be 30x."

I have a 30mm 2" occular with a 600mm scope - what do that give me? 20x ? (don't really know how to convert the "mm" of astro eyepieces to the "x" of spotting scopes. thanks in advance)
 
AlbertoJ said:
I know Zeiss scopes have astro adapters and can use 1/4" and 2" astronomy eyepieces (like Nagler or Pentax XW).
Swarovski has 1/4" astro adapter.

Which other Spotting scopes can use astronomy eyepieces?
Click to expand...

I just noticed in the latest Birdwatch mag. that Hawke are doing an ED Endurance scope that takes 1.25" astro eyepieces see here

I wonder if they are as good as their Frontier bins and will cause a stir like they did.

A UK stockist says the Endurance ED scopes are the equal of their Frontier ED scopes. See here.

Nev
 
Hawke seem to be totally confused with their FOVs and conversions (m@1000yds!!!) and if any of the figures are anywhere near correct then the FOV is disastrously narrow throughout the range.

John
 
Same factory as Celestron Regal 80 and 65mm scopes? The Hawkes Endurance and Celestron look very similar, even down to the fluting on the prism body. The eyepiece locking mechanisms are also the same.

Rmel66.
 
cango said:
"For example let us assume a 20mm 2" occular with a 600mm focal length scope. That would be 30x."

I have a 30mm 2" occular with a 600mm scope - what do that give me? 20x ? (don't really know how to convert the "mm" of astro eyepieces to the "x" of spotting scopes. thanks in advance)
Click to expand...

Yes 20x 600mm[focal length] divided by 30 = 20x 600mm divide by 10mm eyepiece = 60x etc.
 
RJM said:
And no point since the prism clear aperture is never more than 20~25mm. Much smaller than the 27mm fieldstop of the widest 1.25" eyepiece, the 24mm Panoptic.

Rick
Click to expand...

Hi Rick,

I ordered one of those Pentax PF-65EDII scopes from BuyDig.com for $400 with the zoom. I also ordered a Meade 5000 20mm SWA. It has a 68 deg view. Should that work with the Pentax or will the prism clear aperture restrict the FOV? I've been looking at even wider angle eyepieces like the Williams Optics 16mm UWAN which has an 82 deg AFOV.

The fact that the Pentax takes astronomical eyepieces seems to open up lots of possibilities but I'm worried that I don't know enough about telescopes to pick eyepieces that are compatible.

Mark
 
Mark, I can only estimate the Meade has a fieldstop of ~21mm so you will have to measure the Pentax's prism opening yourself.
 
Thanks Rick,

Unfortunately, I have no idea how to do that. Are there websites or books you know of that explain all of this? I've been reading reviews of eyepieces and the authors are using a lot of terminology that I don't understand.

Probably my best bet is to start a thread on the Pentax forum asking members if they have actually tried ultra wide angle eyepieces on their PF-65EDIIs.

Thanks,
Mark
 
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