Viking/Kamakura OEM Eyepiece compatibility (1 Viewer)

Hello,

Tl;dr: would a Viking-branded eyepiece work with a Kamakura-branded spotting scope?


As many are aware, the japanse OEM manufacturer Kamakura produces a lot of 80mm ED scopes that are sold under different brand names in different markets.

For example, I believe that these are all optically identical:

Viking V-80 (England)
Kamakura SP-80 (Sweden)
Ecotone SP-80 (Poland)

However, does anyone know if the eyepieces are compatible across all these scopes? I mean, it would be easy for them to change the bayonet desing ever so slightly for different markets.

Specifically, I am looking for an eyepiece for a Kamakura SP-80 ED (from the Swedish market), and wonder if the Viking 22x LER (sold for the Viking V-80 in the UK) would work.

Hi geastrum.

It would be easy for brands to specify their own bayonets to force people to buy their own eyepieces.
Camera makers have done this for over a hundred years.
I have about twenty different fit monocular converters that convert lenses into scopes. Collected over many years, often bought at low prices. Some have very obscure bayonets.

I got a large number of different high quality mounts for Kilfitt/Zoomar lenses, some movie fittings.
Tamron Adaptall various, Vivitar T4 and Sigma had different adaptors for the same lenses.

However, some mounts for scope eyepieces are the same.
Action Optics Southampton may have some eyepieces that they know fit different scopes.
One way would be to get an eyepiece and try it, maybe the cheapest secondhand eyepiece.

A friend machines different mounts himself.

Cheap extension tubes or old teleconverters have the mounts necessary for different camera mounts and can be used.

There may be 500 different camera mounts from the 1800s onwards.
Not so many scopes, but possibly one hundred different eyepiece mounts?

Good luck.

P.S.
With Opticron eyepieces, there are different mounts for the same scopes from different years and I think many different adapters. So even the same make scope may have different mounts.
It may be that there are actually several hundred different eyepiece mounts in total.

Thanks Binastro.
I think the problem with these exact scopes is that they are so region specific, so differently-branded parts rarely "meet each other", so to speak.

I e-mailed Viking optics UK and they were very willing to help - they thought it would fit, but were not sure. I might advise my friend to try it.

geastrum, one has to be careful.

I had a Zunow 50mm f/1.1 lens brand new boxed in Nikon rangefinder fit.
I put it on a Kiev 4 body and took one roll of film.
The lens is soft wide open but fast. The photos were good.
However, although one may think Nikon, Contax and Kiev rangefinders have the same bayonet, they don't.
The Nikon and Contax may have slightly different registers.
The Kiev was too tight and it scratched the enamel or chrome of the lens.
If one knows this Zunow lens, one realises the significance of this. Brand new or marked, i.e. scratched.

The Topcon and Exakta are also thought to be the same.
I have a Topcon 300mm f/2.8, maybe the first such lens normally available.
I put a Minolta to Exacta adapter on it. It went on but very tightly. I wouldn't like to try to get it off.
I used the Topcon 300mm f/2.8 lens on my Minolta.
A fine lens, but very long and heavy. The tiny Exakta bayonet is probably the reason Exakta and Topcon sales failed. Larger bayonets give the lens maker more latitude. The Miranda has a 44mm thread and an outer bayonet and was used for scientific work. The Praktica/Pentax 42mm.
The latest Nikon Z6/Z7 etc. I think have bigger bayonets for the same reason.

I was being conservative in saying there may be 500 different camera lens fittings. I once began to list the ones I knew. I suspect the real number is well over one thousand, and will never be known accurately.

So the Viking eyepieces may well fit, but when first trying them, take care.

B.

Ecotone (Poland) replied and said that the Ecotone-branded eyepieces would work with the Kamakura SP.
Here's a link to the 22x (€118):
https://en.ecotone.com.pl/produkty/okular-ler-22x.html

This makes me even more certain that the Viking-branded ones would work too. I'll keep updating this thread as I believe someone else might benefit.

Binastro said:

P.S. With Opticron eyepieces, there are different mounts for the same scopes from different years and I think many different adapters. So even the same make scope may have different mounts. It may be that there are actually several hundred different eyepiece mounts in total.

Click to expand...

Except for the early generations of spotting scopes, some of which had imperial rather than metric threads, all the "modern" Opticron range of scopes can be used with more or less all the eyepieces. Early scope models from the 1980s onwards would include the Polarex, Piccolo, Classic IF, Imagic and the first generation HR scopes of the late 90s.

Our current eyepiece connection is a dual screw thread system - one internal, one external - and is and has been used since around 2002 with the arrival of the second generation HR, the MM2 and IS scopes.

The eyepiece adaptors that we supply today are used to move the eyepiece away from the scope body, usually to accomodate the nosepiece inside the body. Early adaptors did provide compatibility across scope ranges.

On the subject of the Viking eyepieces, I note the company says of its "old" 18/22x LER eyepiece that "this eyepiece will fit onto the new Viking ED Pro telescope bodies and performs well". Presumably that means the current ED Pro eyepieces will fit the older scopes.

HTH

Cheers, Pete

Thanks Pete.
I have two MM2s. They look the same but have different eyepieces with the same zoom range.

I discussed at length with the respected eyepiece designer in the U.S. why there was no standard for the simplest eyepiece fitting. The 1.25 inch astro eyepieces.
He said that he had tried to establish a standard, but it had come to nothing, Perhaps now, twenty years later, there is a standard, but probably not.

German, Japanese, American, French, Russian, Chinese and Taiwanese 1.25 inch eyepieces should be the same.
But they are not.
I measured many 1.25 inch eyepieces and found quite large variations.
Also the same with scope drawtubes.
My astronomy friends also measured their eyepieces with similar results.
One of the problems is that 1.25 inches is 31.75mm.
The Russians seem to choose around 31.8mm, the Japanese around 31.7mm.
Some eyepieces are too big to fit, others very loose.
Then there is the question of chrome finish on the barrels. This has a thickness.
I also measured ovality. There is no standard on this.

The only standard may be the old RAS thread, which my 1950s scope had. But these were slow to fit and were replaced with 24.5mm or 0.965 inch then 1.25 inch and later 2 inch fit eyepieces.

Different factories probably have slightly different ideas as to the size of bayonet mounts.

Photography and scopes overlap.
There are Whitworth threads and filter threads that both use.

Microscope eyepieces are about 23.2mm fit. But there is variation here also.

U.K. custom scopes in the early 1970s had no standard sizes. I tried hard to get 1.25 inch and 2 inch sizes standardised and at least partly succeeded.

Opticron MM2 Mighty Midget Travel Scope 52. Made in Japan.
Eyepiece 15x to 40x

MM2 V2
Eyepiece 40903M 15x to 40x with locking collar.

The scopes seem to have one internal thread and two outer threads.

RAS thread is apparently an old BSP British Standard Pipe fitting for standard gas pipes.
1 1/4 diameter 16 TPI. Pitch 1/16th inch.
(Maybe that is where the 1.25 inch push fit came from).

Courtesy of ICEINSPACE Australia. They have spreadsheets of fittings for various telescopes and accessories.

Is the Leica camera 39mm thread also partly Imperial?
(39mm 26 TPI Whitworth).

I think that plastic water pipes may also come in 1.25 inch and 2 inch?