Tal-1 non-standard eye pieces?

[Tal-ly ho]

Hi all! 

I'm new to star gazing and picked up a Tal-1 recently on a bit of an impulse! I hadn't really thought about lenses when I bought it (but it was a bargain!). 

It only came with one lens (15mm) which is great for the moon, lovely clear images, but I'd like more zoom to try and look at other objects. I'm particularly keen to look at Jupiter so was hoping to get a low f ans a barlow lens? 

Here is the problem. I think it's a non-standard fitting. From what I have read the first Tal 1s has a slightly smaller barel than normal. Mine is seriel No.19, so I'm guessing one of the first! 

Does anyone know if its possible to get hold of more lenses for it, or better, have one to sell? 

[johninderby]

0.965 was the standard size for telescopes but nowadays replaced by the 1.25”.

Just search for 0.965 eyepieces or get a 1.25” to 0.965 adaptor.

https://www.amazon.co.uk/Astronomical-Telescope-Eyepiece-Adapter-Aluminium-default/dp/B08DFRH29X/ref=sr_1_4?crid=1KL1I83TN9B15&keywords=0.965+adaptor&qid=1641687838&s=electronics&sprefix=0.965+adaptor%2Celectronics%2C74&sr=1-4

 

Edited January 9, 2022 by johninderby

[johninderby]

You can buy used 0.965” eyepieces from places like this but perhaps not such a good idea to put money into 0.965 eyepieces.

https://ensoptical.co.uk/index.php?route=product/search&search=0.965 eyepiece

Edited January 9, 2022 by johninderby

[John]

Some of the early TAL's had an eyepiece size that was neither 1.25 inch or .965 inch. It was a little smaller than 1.25 inch I seem to recall.

If yours is one of those then it could be tricky to find eyepieces that will fit.

 

[markse68]

Early Tals weren’t 0.965” John- they were 32mm- a little bit bigger than 1.25”. You should be able to use standard eps in your Tal by bending in the thin gripping fingers on the focuser tube, or wrapping a little tape around the ep barrels. You might have to shift the primary mirror up the tube a bit with spacers though to reach focus.

Otherwise Tal eps do come up on ebay from time to time but i’m not sure they had much shorter than the 15mm you have- a barlow could be useful. 

Keep an eye out for the 25mm plossl- it’s very nice

Mark

Edited January 9, 2022 by markse68

[johninderby]

32mm was a Russian microscope eyepiece size.

https://www.ebay.co.uk/itm/223991045223?hash=item3426e81c67:g:x2YAAOSwxOJeptTf

[Roy Challen]

Mark is correct, the early Tal 1 has 32mm focuser. I recently gave mine away and recall that 1.25" eyepieces loosely fit, as Mark said you could wrap some tape to improve the fit. 

However, most modern EPs won't reach focus this way. You'll need to move the primary mirror up the tube by about 25-30mm. There are threads that show how to do this.

Alternatively, you could try and source the specific barlow that came with these scopes. It's a decent unit, and for me at least, gave great views of Jupiter and Saturn last year.

BTW, the 25mm that also came with these scopes is also worth seeking out, better than the 15mm IMO

Edited January 9, 2022 by Roy Challen

[Tal-ly ho]

Hi, 

Thanks all! I have a feeling that I might have one with a slightly smaller than average lens e.g. I bought a 1.25 inch barlow but it's a smidge to big to fit in.... I'll keep an eye out for a Tal barlow and see how it goes! Thanks for your help!

[Tal-ly ho]

After a bit of experimentation, yes, I think you are right on the 32mm lens. I had bought a barlow lens previous to this thread, which fitted in, but of course my slightly fatter lens did not!  I've scoured around for 32mm lenses but not come up with anything, so I think I am going to sell the Tal-1 and find something more standard. Does anyone know the going rate for these?

Cheers,

Rory.

[Roy Challen]

I gave mine away, however I also acquired it for nothing. Is it complete with mount? You could try asking for £75-100, but that'll be the absolute max. 

Shame really, as they're good telescopes.