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Where premium quality meets exceptional value. ZEISS Conquest HDX.

Comprehensive test from Gijs of transmission of 8x30 and 8x32 models (1 Viewer)

John A Roberts

Well-known member
Australia
After several months Gijs has been able to post a new test report! It covers 100 years of 8x30 and 8x32 production, from 1920 on.
Included are various comparison photographs and a number of specification tables (many of the units used are from Jan’s extensive collection).

There are also 14 graphs showing the transmission of a wide variety of single and multicoated models.
Of interest to many will be the transmission data for both the new Swarovski NL 8x32 and the Zeiss SF 8x32.
(and also included is a graph for the Leica Geovid HD-B 8x42 rangefinder binocular i.e. the current 3rd generation version that uses Perger prisms).

See at: Verrekijker testen | House Of Outdoor & Optics


John
 
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I have looked at the results and they are very interesting. But to my eyes Zeiss does very well, and they do not come behind
Swarovski in any way. And, by the way I own many of those tested.
So, that means, as far as brightness, don't look at these tests to gain any real information as it relates to what you will see through the binocular.

In fact, Zeiss seems to excel in viewing brightness, the Conquest HD seems to beat anything in the midrange, and more.
Those transmission results do not always translate to what you will see behind the ocular...
Jerry
 
A respectable forum member commented about a year or so ago that he felt he could not reliably distinguish a shift in brightness any less than 3%. Not long after, a rather disreputable forum member went on to surmise that he was capable of distinguishing a 2% difference....

A 3% difference looks good on paper, but is probably not significant, or even detectable to the normal viewer is my takeaway. The flatter color response also looks better in the graph for the Swaro, but in direct viewing between the two in broad daylight, I don't notice it, but admittedly am not sitting there trying to tweeze out a difference because a chart shows it. There may very well be natural circumstances where it is more readily apparent than others.

Bottom line: both are very good binoculars.

-B.
 
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And thank you Gijs, for your thorough tests and very useful comparative documentation. Much appreciated, whether my experience parallels yours or not on some issues. ;-) Very well done.

-Bill
 
The GPO Passion ED 8x32 look impressive. Roughly the same transmission as the Victory SF and quite a bit lighter. Too bad the eye relief is only 13mm. I guess you can't have everything for 1/6 the price.
 
Seems like Zeiss has lost the recipe for the secret sauce for brightness…hitting 93% in 2004 and higher later with the HT
SF32 has a significantly more complex eyepieces than even SF42 so more glass seems to be what is behind a drop in recent transmission.

Lee
 
To illustrate Lee’s observation:
a) Zeiss SF 32 optical construction
b) Swarovski NL 42 (and likely 32) optical construction

The former was provided by Zeiss when the SF 32 was introduced. For comparison, see an image of the different construction of the SF 42, along with more detail regarding the SF 32, in post #326 at: x32 SF

The latter is from mnich, via Arek at Allbinos: Optical construction of Swarovski NL Pure binoculars - AllBinos.com
And although we don’t have an image of the NL 32 construction, we do know that both the NL 32 and 42 have the same number of lenses (see the technical data sheet).
So while the NL 32 and 42 eyepiece lenses will likely differ in smaller details e.g. curvature and relative thickness, each eyepiece has 6 lenses. And most likely in the same 2, 1, 2, 1 configuration, to accomplish the same flat field and wide FOV functions.


John
 

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  • 8x42 Front.jpg
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  • NL Technical Data (04:2021).pdf
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Brightness is an ongoing subject to be discussed on this forum, there fore it may be useful to repeat what I have stated before, see "Color vision, brightness, resolution and contrast in binocular images" a review paper I have published on the WEB-site of House of Outdoor also.
In that paper I have argued, that brightness is a psycholgical phenomen determined by the follwing parameters:
  • size of the exit pupil
  • the amount of light transmitted
  • the color distribution of the transmitted light. Blue and green are judged by our optical system as brighter than red for example.
Swarovski has succeeded to realise high light transmissions over a broad wavelength range: the spectra are often almost flat from blue to red so the transmitted light hits all optical/visual parameters.
Gijs van Ginkel
 
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