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ZEISS DIASCOPE 20-75x zoom and ZEISS Victory Vario Eyepiece

accessories equipment eyepieces optics
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#1 Huan

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Posted 07 August 2020 - 12:52 PM

I read this wonderful thread and realized that I need a ZEISS DIASCOPE 20-75x zoom, 25.1mm to 6.9mm:
https://www.cloudyni...-zoom-eyepiece/
 
Upon checking, however, this dreaming eyepiece has long gone. I cannot find it anywhere. Meanwhile, I found ZEISS Victory Vario Eyepiece is readily available; focal length range unknown:
https://www.bhphotov...epiece_for.html
 
My question is how similar they are in terms of optics and specs. Is ZEISS Victory Vario Eyepiece is good replacement for ZEISS DIASCOPE 20-75x zoom?

 

***

 

Update: and what adapter/accessories I will need to fit ZEISS Victory Vario Eyepiece to a 1.25" diagonal if I purchase one?


Edited by Huan, 07 August 2020 - 12:57 PM.


#2 areyoukiddingme

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Posted 07 August 2020 - 01:03 PM

I'd be interested to hear too . . . From what I can glean:

 

I see from the specs that it is a constant 72 degrees throughout the range. And the range is 3x. 

 

However, when I look at the scope it is matched to, the focus is on the body of the scope.

 

There must be optics in the body of the scope that are necessary for this to work. Indeed, the Zeiss homepage says the scope has a focal length of 162 to 486mm for the 85mm objective. So clearly something whacky is happening inside the scope.

 

That makes me think that this eyepiece won't be something that can be adapted to an astronomical telescope.

 

Oh, and I see that the eyepiece is listed as having a 7.48mm focal length! It doesn't appear to be a zoom!



#3 Huan

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Posted 07 August 2020 - 01:10 PM

 

There must be optics in the body of the scope that are necessary for this to work. Indeed, the Zeiss homepage says the scope has a focal length of 162 to 486mm for the 85mm objective. So clearly something whacky is happening inside the scope.

 

That makes me think that this eyepiece won't be something that can be adapted to an astronomical telescope.

 

Oh, and I see that the eyepiece is listed as having a 7.48mm focal length! It doesn't appear to be a zoom!

OOPS...so the zoom part is in the body of the scopes ( Harpia 85 Scope and Harpia 95 Scope ), I guess?



#4 areyoukiddingme

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Posted 07 August 2020 - 02:39 PM

Alas, it looks that way. Hopefully someone with direct experience can chime in, but the stubby looking eyepiece doesn't have the length I'd expect for it to zoom, and all of the specifications suggest that there is some kind of moving barlow mechanism in the focuser of the scope.

 

However, it should be possible in principle to copy such a mechanism and adapt it to an astronomical telescope. That would be interesting.

 

Maybe someone can explain how it works? 

 

One other thought . . . if it really is the case that the eyepiece is a ~7mm, then the internal 'zoom' mechanism must actually be both a reducer and barlow. Hmm.


Edited by areyoukiddingme, 07 August 2020 - 02:40 PM.


#5 areyoukiddingme

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Posted 07 August 2020 - 02:43 PM

Yep. A set of Delos in one zoom? :-)

 

https://www.youtube....h?v=0wO2336_GCQ



#6 DRodrigues

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Posted 08 August 2020 - 02:03 PM

More info about the new Zeiss ep https://www.cloudyni...ew-zeiss-748mm/ - it's a compact ep but might be not the best for fast astro scopes... Astro eps seem to improve much the Harpia scope...




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