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Identification of the optical formula of the Zeiss Conquest hd 10x42 (1 Viewer)


Active member
Does anyone know the optical formula of the Zeiss Conquest hd 10x42? How many lenses in how many groups does it have? It seems that the objective lens is a triplet (2+1). What about the eyepieces? Maybe someone who repairs binoculars should know. Thank you in advance!

John A Roberts

Well-known member
Hi dorubird,

Zeiss does publish some limited information about optical construction, mainly in the form of cutaway images for some of the Victory line
- but not so for the lesser lines like the Conquest or Terra.
e.g. see the mega-thread of Zeiss images at: https://www.birdforum.net/threads/zeiss-collection-of-cross-section-and-cutaway-images.385822/ *

Roger Vine has published some information as to the objective construction of the Conquest HD’s, based on his own observations using a laser pointer
(and of which you seem to be aware). See at: http://www.scopeviews.co.uk/BinoReviews.htm

The Conquest HD’s 2, 1 + 1 objective construction (a cemented pair and then a single lens, followed by a single focusing lens), is typical for many modern roof prism designs, including those of Leica. In contrast, the Zeiss Victory line mainly uses a 1, 2 +1 pattern (see post #49 in the above thread), as do the high-end Swarovski’s.

As to the eyepiece construction, it will almost certainly consist of three groups (as it’s not a specialised flat field design, more complexity is unnecessary). And most likely two of the groups will be cemented pairs, but as to which will depend on what particular balance of aberrations the designers wished to control for.

* Both Swarovski and Leica also publish cutaway images of some of their high-end lines. And Swarovski also usefully publishes details of the numbers of lenses used in its products, as did Leica until recently.

And while there are also additional images on the net from those who've had actual units cross-sectioned, I've not seen any of the Conquest HD's.

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Active member
So it seems that most likely Zeiss Conquest HD has the formula: (2 + 1 objective) + (1 focus lens) + (2 + 2 + 1 eyepiece)
Thank you so much John! Extraordinary mega thread!(y)

I have a laser pointer for astronomy, but I don't know how to look at the number of lenses alike Roger Vine!


Active member


  • Zeiss Conquest HD objective.jpg
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  • Zeiss Conquest HD prism reflex.jpg
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