Does Opticron SDL v3 eyepiece fit Kowa TSN-4? (2 Viewers)

[THE_FERN]

I understand the v2 does. When I phoned, Opticron suggested the dimensions of the v3 are slightly different. Does anyone know if it fits?

Tx

 

[dwatsonbirder]

@jring is the man who will be able to help, the short answer appears to be no-one has tried, though it may be possible with some washers (depending on whether your scope has an additional "window" over the prism.

 

[paddyluke]

I understand the v2 does. When I phoned, Opticron suggested the dimensions of the v3 are slightly different. Does anyone know if it fits?

Tx

the SDL v2 & v3 should have identical fitting as they are made for the same scopes,

 

[THE_FERN]

the SDL v2 & v3 should have identical fitting as they are made for the same scopes,

Thanks for this. Opticron suggested (but didn't state explicitly) that the v3 may extend further into the body of the scope. This could be an issue with the Kowa. Wonder if there are technical specs/docs which will make this clear.

...Can't find a dealer in easy reach in London who has one in stock to try. Not Wex according to their www and not London Camera Exchange.

 

[wllmspd]

If you need any dimensions from a v3 do shout and I’ll get the calipers out.

Peter

 

[jring]

Hi,

it seems I was summoned... I had a private conversation with an inactive BF member in 2021 who did adapt his SDLv3 to his TSN-4 with very good results using two O-rings with a total height of 5-6mm.
I had asked him to post an image of the adaption and/or measurements in the Kowa Eyepiece compatibility thread but did myself post what I knew when nothing happened.

As for measurements, the distance from the front element protrusion to the base plate at the end of the protrusion would be helpful to compare with the SDLv2 and other EPs...

Joachim

 

[THE_FERN]

Hi,

it seems I was summoned... I had a private conversation with an inactive BF member in 2021 who did adapt his SDLv3 to his TSN-4 with very good results using two O-rings with a total height of 5-6mm.
I had asked him to post an image of the adaption and/or measurements in the Kowa Eyepice compatibilty thread but did myself post what I knew when nothing happened.

As for measurements, the distance from the front element protrusion to the base plate at the end of the protrusion would be helpful to compare with the SDLv2 and other EPs...

Joachim

Thanks very much for this. It gives me the confidence to press on... Never having done this before, I assume obtaining the appropriate o rings should be straight forward..?

 

[Grando]

In terms of o-rings it should be pretty straightforward. Easiest will probably be a visit to a local plumbing supplies place, as they should have a box of larger o-rings and you should be able to check if they fit onto the underside of the eyepiece correctly.

 

[THE_FERN]

In terms of o-rings it should be pretty straightforward. Easiest will probably be a visit to a local plumbing supplies place, as they should have a box of larger o-rings and you should be able to check if they fit onto the underside of the eyepiece correctly.

Cheers

 

[wllmspd]

O-rings are specified by diameter and diameter of the rubber itself… pretty self explanatory, though need a quick converter for ID/OD. Lots of different material options, which you won’t care about. Taking your eyepiece to a plumbing shop is probably the simplest idea!

Peter

 

[jring]

Hi,

my original conversation with BF member johnf3f about adapting the SDLv2 states 4.5mm thickness and a diameter of 38 to 40mm for the O-ring. My measurements are 4.5mm thickness and 41mm as it sits in the EP with a 1mm gap (which makes it easier to get it in there). So if you cut a 40mm diameter ring you will probably be just right - if the diameter is a bit larger, it doesn't matter as you can cut it down until it fits.

The critical measure we would need from the SDLv3 is this here... on my v2 it's 22.5mm. This determines whether the EP will fit the scope. This number plus 4.5mm for the O-ring should be less than the measure from the upper end of the accessory thread of the Kowa body down to either the prism or the protective glass...



PS: Sorry for dust and the tiny O-ring you see is stock and not the one used for adaption - this would be on the outside but was removed for measuring when I took the image...

Cheers,

Joachim