[karmantra]

In the U.S. it is just about impossible to get any of the fixed eyepieces or even the zoom for the Fieldscopes, other than what they came with. Are there any fixed/zoom eyepieces from other manufacturers than would fit & work with the Fieldscope? Or an adapter that would fit between an eyepiece and the scope itself? I may be asking the impossible, but I do know that ZenRay & Vortex make eyepieces that mount onto Swaro scopes. Has anyone experimented with alternatives?
Nikon could eliminate this issue if they made availability a priority, but there must be a marketing reason for not doing so!

[LabradorDuck]

You can still get the fixed eyepieces from Amazon Japan, but you have to use a forwarding service like Tenso.com since they don't ship to the US. This adds to the price, but I still got mine for less than list price (far less that what I've seen on eBay).

Theron/Avian/Bosma makes knockoff Nikon-like scopes (no 50mm ones though), and their eyepieces should in theory fit the ED50, but I seem to recall reading that certain eyepieces don't *quite* fit certain scopes for weird reasons. Optically, reviews vary from "decent" to "almost indistinguishable from Nikon, so generally positive. Hopefully someone who has used these will weigh in.

[FrankD]

I have tried the Theron (Bosma) 30x and 25-75x in the Nikon ED 50. I posted a thread about it in the main spotting scope forum several months ago.

Basically, both will "fit" in the ED 50 but the threads aren't an exact match so they don't fully "seat" into the scope. They won't fall out of the scope if it is flipped upside down but they aren't fully into the scope. Optically they work without any issues in terms of near or infinity focus and the overall optical performance is very good if not quite at the level of their Nikon counterparts. The difference, in my experience, seems to fall into the area of color rendition (slightly warm bias in the 30x in particular).

[kerryd]

Careful which body you try the Bosma on. It will not fit the straight ed50.

[mikefreiberg]

Originally Posted by FrankD

I have tried the Theron (Bosma) 30x and 25-75x in the Nikon ED 50. I posted a thread about it in the main spotting scope forum several months ago.

Basically, both will "fit" in the ED 50 but the threads aren't an exact match so they don't fully "seat" into the scope. They won't fall out of the scope if it is flipped upside down but they aren't fully into the scope. Optically they work without any issues in terms of near or infinity focus and the overall optical performance is very good if not quite at the level of their Nikon counterparts. The difference, in my experience, seems to fall into the area of color rendition (slightly warm bias in the 30x in particular).

Hi Frank,

This is interesting to find out something that "almost" fits the Nikon threads. Any vignetting at all? Did any of the threads strip by chance? Thanks for posting!

All the best,
Mike Freiberg
Nikon Birding Market Specialist

[FrankD]

Mike,

Kerry's comments above are correct. I should have been more specific. The 30x Bosma wide angle eyepiece fits in the Ed50 angled but not the Ed50 straight. The Bosma zoom fits in both ED50 styles.

The threads partially engage but the eyepieces don't seat completely. I posted a thread detailing this in the main forum. I believe it was titled Nikon ED50 and Theron Optics Mag82.

The threads did not strip and there was no vignetting.

[mayoayo]

I dont see the eyepieces for sale in their site,only as a part of the MAG82 kit...A good deal in the scope though,895$ including the two eyepieces seems excellent value

I would love to be able to buy the eyepieces as a complement for my 27X DS in the ED50,and to try and adapt them to work in a Kowa 823 that I am fixing..

[soultime]

Originally Posted by mayoayo

I dont see the eyepieces for sale in their site,only as a part of the MAG82 kit...A good deal in the scope though,895$ including the two eyepieces seems excellent value

I would love to be able to buy the eyepieces as a complement for my 27X DS in the ED50,and to try and adapt them to work in a Kowa 823 that I am fixing..

Having purchased the Bosma 30x both in the kit and also separately online (at a good price) it is certainly something I would not recommend. One of them is obviously a lot les than 30x magnification with lots of edge distortion and the other appears to be more like 38x than 30 when compared side by side with other scopes. Quality control issues methinks.
Both the fixed and zoom are available separately in the UK under the Avian brand, though expensive in my opinion.

Andy

[FrankD]

The 30x was also available online at some very attractive prices. Kerry purchased one but it didn't work with his ED 50 straight. I think the was looking to sell it. Maybe a PM would be in order Manuel.

[mayoayo]

Thanks Frank..I,ll do that...The Bosma 30X would be an equivalent in focal to the 24-30X Nikon ,..So +/-16X in the ED50..right?...I have seen the bosma clon of the Nikon Zoom in some Astro configurations lately,I wonder if other focal lenghts of these series are avalilable..

[FrankD]

I saw the astro version of the Nikon zoom as well. Henry pointed it out. I forget who was making it. Williams optics?

I haven't seen any of the wide angle Nikins in a 1.25 inch configuration yet but will keep an eye out for them. It shouldn't be hard to do as my Bosma 30x almost fits nicely into the 1.25 inch sleeve in my Promaster. The optical performance was certainly pleasing.

[mayoayo]

Frank,,I dont remember If W.O has a version of the Nikon zoom..I saw a few different brands of a similar model the other day,while searching Ebay for Zooms..I saw some other astro eyepieces that looked just like the ZEN ED 82 / Vortex Razor 30XWA, but with a 1 1/4 barrel screwed in the thread, instead of the bayonet,

By the Way,,Kerry is selling me the Bosma 30X, thanks for the tip!..It will be a great complement for the 27XDS..Ill get 16X on the ED50,and 26X on the Kowa 823!

[mayoayo]

Originally Posted by FrankD

Mike,

Kerry's comments above are correct. I should have been more specific. The 30x Bosma wide angle eyepiece fits in the Ed50 angled but not the Ed50 straight. The Bosma zoom fits in both ED50 styles.

The threads partially engage but the eyepieces don't seat completely. I posted a thread detailing this in the main forum. I believe it was titled Nikon ED50 and Theron Optics Mag82.

The threads did not strip and there was no vignetting.

Frank,,This does not make sense..The Mount is identical in both scopes,..the difference lies in the scope body,but the mount is not altered....Did You try the same eyepiece on a straight and Angled scope and found this to be true?
Or two different eyepieces were tried,.. Kerry´s eyepiece in his straight scope and Yours in an angled?...This could be a sample variation or defect in the Eyepieces,perhaps even different makers are being compared,and their thread design varies a bit...
Perhaps His eyepiece and Yours are not the same..

[FrankD]

Actually I had a straight ED 50 for a brief time last summer and an angled version for a longer stint last November a nd December. The Theron 30x would not mount at all in the straight though the Theron zoom would partially seat into the threads. The angled ED 50 partially seated both eyepieces. I don't have an explanation really. Manufacturing tolerances maybe between both units. Interesting though that the zoom fit in both.

As I mentioned above I posted a detailed thread on it with pics last December.

[NDhunter]

A bit of advice here is don't try to partially or seat any odd eyepiece onto another
scope where there is not a good fit. It seems to be a sure way to flub or mess up
the threads on either or both.

I look at this as poor advice.

A push fit or whatever will void any warranty is not advised.

Jerry

[FrankD]

Here is the thread I mentioned.

http://www.birdforum.net/showthread....ghlight=Theron

Jerry's advice is sound. I believe there is even a disclaimer on Theron's website to that extent.

Still it was interesting to try though I didn't try to force the issue. I can see where others might. A gentle touch would certainly be in order.

[bcskr]

Pelee Wings ,in Canada has the MC II 20x WA eyepiece in stock, their toll free number is 1-877-326-5193.

[woodhornbirder]

Originally Posted by FrankD

I saw the astro version of the Nikon zoom as well. Henry pointed it out. I forget who was making it. Williams optics?

I haven't seen any of the wide angle Nikins in a 1.25 inch configuration yet but will keep an eye out for them. It shouldn't be hard to do as my Bosma 30x almost fits nicely into the 1.25 inch sleeve in my Promaster. The optical performance was certainly pleasing.

http://www.kkohki.com/English/kkohkiparts.html#Nikon

very expensive eps....but top quality. Probably better options out there with same performance/