1.25" eyepiece adapter for spotting scope (1 Viewer)

I have a great Fujinion 60mm scope with a fixed 25x eyepiece. I would like the option for a little more reach at times, but these are fairly rare and extra eyepieces are nonexistent.

The the threads for the EP cover are 78mm male. If I use one of the generic 2" to 1.25" astronomical EP adapters that fit that thread size, would a 1.25" EP come to focus on my scope?

My other option is the Vortex Doubler. These seem to get decent reviews and may also work well with my Canon IS bins.

Are you sure 78mm?

2 inch to 1.25 inch adapters are usually long.

I use 24.5mm or 0.965 inch fitting eyepieces with some spotting scopes.

Sometimes I just remove the barrels of astro eyepieces by unscrewing them to get focus on spotting scopes.

I have not had success with the Canon 18x50 IS and afocal doublers.
Maybe they work with lower magnification Canon IS binoculars.

Binastro said:

Sometimes I just remove the barrels of astro eyepieces by unscrewing them to get focus on spotting scopes.

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Hi,

yes, that is an option but one should check if the EP in question has elements inside the barrel, which is quite common with more complex designs (Nagler et al.).

Also proper care is a good idea, some EPs fall apart after unscrewing the barrel (Televue has some models but has a warning in the instructions).

It is probably a good idea to have the EP standing on the eyelens on some soft surface when trying this, so you won't be left with a pile of glass to sort out...

Joachim

Thanks for that Joachim.

I found a shop with 6 Leitz Colorplan 90mm f/2.5 Pradovit lenses in the silver coloured metal mounts that didn't work.
They all had been incorrectly reassembled. But otherwise excellent.
I bought them for a fiver each.

So I unscrewed one and all the single elements, no cemented pairs because of heat, and spacers I think, tumbled out.
I figured how they should be placed and reassembled them.

I offered them all at what I thought was a reasonable £15 each at a camera meet.

They were all sold in minutes.

Once I also touched the glass filter in the Pradovit. It burnt my hand. It was the heat filter. It didn't look hot.

I have not had success with the Canon 18x50 IS and afocal doublers.
Maybe they work with lower magnification Canon IS binoculars.

Thank you. That is helpful. I have the 12x. I was already concerned that the image would not be bright enough, but thought the IS might be enough at 24x if sitting in a stable position. The Canon's with a doubler would be a impromptu alternative to a spotting scope, so I probably would not have a tripod with me in those situations. If I was carrying the tripod, I would also be carrying the scope.

Binastro said:

Are you sure 78mm?
The male threads are about 77.5MM

This is the type adapter I was looking at. The twist lock design should allow me to fine tune the seating depth, but I will be limited on how close I can adjust the EP.

William Optics 2"-1.25" RotoLock Eyepiece Adapter w/ T Thread ROTO-A2-125-M42F

https://www.highpointscientific.com...id5D0_4fiO8tYwF3J3EUO85py5kIYTBhoC7j0QAvD_BwE

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Is my likely challenge going to be that the 1.25" EP is too close or too far to achieve focus? If it is too close, I could just use an extension tube like this.

https://www.ebay.com/itm/1-25-Teles...760724?hash=item36282533d4:g:d7QAAOSwUYNaOFou

Too far, possibly.

Binastro said:

They all had been incorrectly reassembled. But otherwise excellent.

Click to expand...

Lol - yeah, if you're in a position to fix this, good for you. Cloudynights has some stories of hefty repair bills to clean and reassemble the heap of glass that once was a Panoptic...

Joachim

A lot easier than Rubik's cube.

I took a really old drawtube telescope to Horace Dall that I couldn't get into.
He just gave it a might tug and it pulled apart.

Someone claimed that he had a 5.5 inch fine telescope objective. I tested it on the spot and I said that it gave a poor image.
But I could ask a world expert if he wanted me to get a proper opinion.
It took quite a time to go to Horace and he just looked at it and said it was half a Petzval lens, not a telescope objective.

When I took it back to the owner he threatened to call the police saying he thought that I had stolen it.
I learnt to stop trying to help people by seeking out world class optical skills.

No good deed goes unpunished.

P.S.
The only real failure that I recall was taking apart a very high quality aircraft lens.
When I opened it perhaps a hundred tiny ball bearings fell out.

Generally lenses follow a sensible pattern, but I didn't expect these ball bearings.