Helios & Nikon
New member

Hi - I have just acquired a Helios Rangemaster A90R spotting scope and would like to link it to my Nikon DSLR. I’m totally new to digiscoping though and would appreciate a few pointers specific to my setup.
I see that, at the base of the eyepiece, there is an external thread (currently protected by a slim, screw-on collar. I presume that if I unscrew this collar I can replace it with a screw-on T-adapter, onto which I can then screw a T-mount for my Nikon. Does anyone: (a) know what the external thread size around the base of the eyepiece on the Helios is (it looks to be around 50mm or 1,15/16”???) and (b) where I might find the right screw-on T-adapter?
It’s my understanding that the thread for the T-mount is standard (42mm), so the mount for any DSLR (Nikon, Canon, etc) would be interchangeable on the same T-adapter - is that right?
Finally, does anybody here know of a website where I could find the technical specs for the scope - a user guide or manual would be useful, and may help answer the questions above.
Thanks!
I see that, at the base of the eyepiece, there is an external thread (currently protected by a slim, screw-on collar. I presume that if I unscrew this collar I can replace it with a screw-on T-adapter, onto which I can then screw a T-mount for my Nikon. Does anyone: (a) know what the external thread size around the base of the eyepiece on the Helios is (it looks to be around 50mm or 1,15/16”???) and (b) where I might find the right screw-on T-adapter?
It’s my understanding that the thread for the T-mount is standard (42mm), so the mount for any DSLR (Nikon, Canon, etc) would be interchangeable on the same T-adapter - is that right?
Finally, does anybody here know of a website where I could find the technical specs for the scope - a user guide or manual would be useful, and may help answer the questions above.
Thanks!
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