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Video review (english subtitles) of Zeiss Dialyt 18-45X65 (1 Viewer)

Quick question: how 'obviously NOT wide angle' does this scope feel? to give you an idea, I have a Swaro ATS, and I cannot use the 20-60 zoom, it feel way too much like looking through a paper tube -- the 25-50wa zoom is more acceptable to my eye. I do a lot of walking around when I do not want to carry a tripod, but I would like something more than my conquest 8x42 -- so far I have settled on an Optolyth Mini 25x70, but the Dialyt is interesting because it is sealed, but I was put off by the lack of wide angle (the Optolyth has its limitations, but it has a 50 metres at 1km field of view).
On the Binomania site, Piergiovanni has also included an extensive written description of his impressions (see the link in the original post).
As it will be of interest to some, I've put it through Google Translate and applied some minor adjustments and formatting . . .

Video Review Zeiss Dialyt 18-45x65
August 6, 2021 by Piergiovanni Salimbeni

Within Binomania.it and on the YouTube channel I have often described the performance of classic spotting scopes for naturalistic and hunting use. This time, however, I would like to tell you about a very specialised product that has three enviable strengths: robustness, lightness and speed of use. Such an instrument can easily be defined as a "field spotter" or field telescope.

I'm talking about the Zeiss Dialyt 18-45x65 which was kindly provided to me by Bignami, official distributor of Zeiss products here in Italy. Many hunters have enjoyed its performance for some time, however, I have noticed how easily it is usable in other areas. It costs 1599 Euros and benefits from a two-year warranty, extendable to three.

I start by confirming that the Dialyt is light, despite having a zoom eyepiece, it weighs, in fact, 1230 grams [ just over 43 oz ] which are distributed over just under 40 cm [ around 16” ]. It is very sturdy, it is the classic product that could fall from your backpack or tripod without arousing major worries.

I know many enthusiasts who avoid using their famous spotting scope in the rain or in places where it is easy to fall, just to avoid damaging it. The Zeiss Dialyt 18-45x65, on the other hand, is a tank or if you prefer a submarine; even the caps protecting the optical components are designed to withstand shocks. I believe that the classicism of design is the formula for this success. The armour is also thick in the lens area, the entire optical hull is completely wrapped in it. It is also filled with nitrogen and waterproofed up to 400 mbar.

The focusing system takes place by rotating the 65 mm diameter lens bell. I have estimated a minimum focusing distance of about ten meters [ 33 ft ]. From this position it is necessary to rotate the objective a little more than one and a half turns (counter-clockwise) to reach infinity. From 30 to 35 meters, less than half a turn is enough to observe at a long distance. The rotating movement is precise and some force must be applied. This is perfect for not accidentally losing focus.

Thanks to the good depth of field available at 18x it is perfect for various types of observation on medium-long distance subjects. I have ascertained that thanks to the visual accommodation I have an excellent perception of the depth of field between 50 meters and 150 meters, the distances at which I usually observe wild boar, deer and roe deer. In any case, if the optical theory is not an opinion at 18x from 324 (double the magnification) to infinity, everything will be in focus [ this sentence seems to have lost meaning in translation ].

In summary, as regards its construction, if I had to define it with three simple adjectives, I would say: minimalist, robust and reliable.

The optics of the Zeiss Dialyt 18-45x65 are Made in Japan, consisting of five high-quality achromatic elements and a Schmidt / Pechan roof prism with T * treatment, with transmission values up to 85% of the optical system total.

The sharpness and contrast are excellent, in fact, even if it is not an apochromatic lens and you notice a little residual chromatism, the difference with cheap products is evident by increasing the magnifications. The Dialyt, in fact, remains sharp and contrasted even at 45x.

A respectable compact field scope must have a zoom eyepiece to be able to adapt to the multiple needs of an outing, be it hunting or simply naturalistic. The eyepiece provides an excursion range between 18x and 45x, therefore with a multiplication factor of 2.5x. The exit pupil is between 3.6 - 1.4 mm while the linear field at 1000 m is enclosed between 40m and 23m.

You will therefore understand that at low magnifications the pupil is pleasantly bright for most observations but that it is not possible to take advantage of a very wide-angle apparent field (just over 41 degrees). At 45x, however, it provides almost 60 degrees of apparent field.

A praise to the eyecup; very comfortable which is also retractable to facilitate use with glasses and moreover it is able to protect the field lens very well from accidental falls. You will have to find the right feeling to avoid a bit of a blackout effect at low magnification which in my case has disappeared, resting the eyebrow arch on the upper edge of the rubber.

The Zeiss Dialyt 18-45x65 is also optimised with the well-known Zeiss T * treatment which allows a significant increase in contrast compared to decidedly cheaper field scopes. Nothing to complain, in short, and I can only praise it.

I will not be very detailed because being equipped with a zoom eyepiece the performance varies with the magnification.

At low magnifications it is very well contained, similar to many products defined as HD or semi APO; it is perceived, sometimes, but not always, at high magnifications on backlit subjects.

Also in this case, it varies according to the magnification and lighting conditions. On average, it is present at the extreme edges of the field as a faint violet green halo that is not very perceptible.

Thanks to the modest field of view at low magnification, there is not much curvature of the field. It is fussy to check the loss of resolving power at the edges, so much so that by bringing the details of a deer from the centre to the edge, the image is always very legible. The situation improves already at 30x up to the maximum magnification, where the curvature of the field is very well corrected.

It is present in the pincushion and obviously shows much more at low magnifications. It is a telescope created to “brush left and right” in search of animals or other details, I personally appreciated it very much, I believe that it provides a natural and not tiring image.

It is not an astronomical telescope but I know some enthusiasts who often point it towards the sky, especially when they are in the high mountains, so I could not avoid testing it on the stars. I deduced, therefore, that at 18x starting from about 75% there is a bit of coma and astigmatism which decreases at high magnifications, where it is present, almost at the edge.

I will not be prolix. With the Zeiss Dialyt 18-45x65 you can forget: heavy backpacks, sturdy tripods, fixed eyepieces of various focal lengths and focusing problems. It is minimalist but well built.

Thanks to the rotation of the cell that contains the objective, it is possible to be very precise even with winter gloves, an operation that is often not feasible with compact spotting scopes equipped with the classic focus near the eyepiece.

The sharpness and contrast are at the highest levels, the magnification range is perfect for all kinds of daytime observation and at dusk at 18x it always shows various details.

I appreciated this concept of Zeiss Dialyt, which in astronomy is defined as "grab and go", or "get to go”. In fact I made some outings without even feeling the need to use a tripod, as in this case. It was enough for me to place it on a cushion filled with sand, over the car window, press it against the trunk of a tree or on the parapet of the roof terrace. In some cases it would also be possible to choose a dry branch found directly in the field and set up a very quick support with a small knife.

At 18x with a little practice, you can do some panning, preferably seated using your elbows for support.

It can be easily stored in a backpack together with dozens of other accessories and they could also make you make some short astronomical observations, since at the maximum magnifications the lunar craters are clearly visible, as well as the brightest galaxies.

The straight view is also useful for various types of observation, especially when observing, for example, from a height or from a lookout tower, as in my case.

• Robust and reliable
• Precise focus
• Perfect magnification range
• Zeiss T multi-layer treatment
• It does not require very sturdy tripods
• It can be transported anytime, anywhere

• For purists the optics are not apochromatic so expect some chromatic aberration
• At low magnification the apparent field of view is narrow

I believe that the Zeiss Dialyt 18-45x65 is a minimalist, essential, robust and performing product able to satisfy both the most demanding hunter and the hiker who needs high magnifications but has to deal with the overall dimensions. It is a field scope designed and built to last a lifetime.
If you love this kind of quality, this is the right product for you.

The Zeiss Dialyt 18-45x65 costs 1599 Euros and benefits from a three-year warranty.

As always, I thank Andy de Santis from Bignami for providing the specimen subject of this test and for allowing us to scramble it a bit.


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For the non divers among us, 400 mbar means resistance to 3 meters under water but for how long isn't answered.
There is a DIN code for it, which I've forgotten. Some have 5 minutes resistance and others 2 hours etc. So 400 is nice but the time factor is more important to me.
I have all the confidence in the world that John will tune in.


I asked the question to Zeiss why the US has lifetime and Europe 2 years warranty on the Terra and their answer was it was a matter of marketing strategy.
I assume it's the same for the Conquest.

Hi Jan,

The Conquest HD should be at least ten years.

I have two such binoculars, but I don't know what the warranty is.

You probably mean a Conquest scope.

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Hi Jan (post #6) 🎼 🎹,

I’m not surprised that there is a standardised measure for the waterproofness of commercial optical devices, though I’ve not noticed reference to it before.
And logically it would need to include the two variables of intensity and duration.

Traditionally, Zeiss, Leica and Swarovski have all given a single figure, but only for intensity. It's either been a direct one in terms of pressure
(Zeiss and previously Swarovski), or a derived one with immersion depth (Leica and currently Swarovski).

However in marked contrast, the most recent catalogue from Zeiss (the Hunting version dated 11/ 2020), includes both intensity and duration specifications
e.g see the examples where the intensity (both listed as pressure and depth) varies with the product line, but the time is a constant at 2 hours
- so perhaps the 'norm' that you were thinking of?



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Hi John, post 10

Yes I did but there is a standard for it like some DIN or ISO norm.
I'll see if I can find it.
If my memory serves me well, I think Bill ever mentioned it.

Hi Jan,

ISO 9022: 'Optics and optical instruments - Environmental test methods - Part 8: High pressure, low pressure, immersion' ?



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For an idea of some of the environmental testing practices and standards used in the optics industry, see the following list from Meopta that includes various parts of ISO 9022 . . .

Climatic tests
Temperature tests
• Low and high temperatures for both operation and storage, including very high storage temperatures (up to 300°C) – ISO 9022-2, EN 60068-2-1, EN 60068-2-2, MIL-STD 810G
• Slow and fast temperature changes – ISO 9022-2, EN 60068-2-14, MIL-STD 810G
• Temperature shocks - ISO 9022-2, EN 60068-2-14, MIL-STD 810G
• Temperature tests at reduced pressure - ISO 9022-5, EN 60068-2-13

Humidity tests
• Constant and cyclic humidity tests for both operation and storage - ISO 9022-2, EN 60068-2-3, EN 60068-2-30, EN 60068-2-66, EN 60068-2-78, MIL-STD 810G
• Rain test – ISO 9022-7, MIL-STD 810G

Salt spray tests
• ISO 9022-4, EN ISO 9227, ASTM B117

Mechanical resistance tests
• Vibration tests - Sinus and random vibrations - ISO 9022-3, EN 60068-2-6, MIL-STD 810G
• Mechanical shocks - ISO 9022-3, EN 60068-2-27, MIL-STD 810G
• Combined tests – vibration at low and high temperatures – ISO 9022-10, EN 60068-2-40, EN 60068-2-41

Other tests
• Dust test - ISO 9022-6
• UV, fluorescence and condensation tests – ASTM G154, ISO 11507 meth. A,B, EN 927-6, ISO 4892-3 cycles 1, 2, 6
• Immersion tests - ISO 9022-8, MIL-STD 810G

The information can be found at: Environmental Testing | Meopta :: Better view of the world
And is part of the main Meopta site at: Home | Meopta :: Better view of the world

- - - -
The Meopta group provides a diverse range of services, and produces a wide range of products. For some appreciation, see an image outlining the variety of markets/ products in relation to industrial and OEM services.

The main site is organised into 3 main streams: Industrial, Sport & Lifestyle, and Military. See a copy of the general site map that’s at the foot of each page.

And for the technically inclined, the Industrial screen flow includes a variety of details. Within it, the Manufacturing page links to a set of pages of particular interest, see the screen grab. The page is at: Manufacturing | Meopta :: Better view of the world



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Sul sito di Binomania, Piergiovanni ha inserito anche un'ampia descrizione scritta delle sue impressioni (si veda il link nel post originale).
Poiché sarà di interesse per alcuni, l'ho inserito tramite Google Translate e applicato alcune piccole modifiche e formattazioni . . .

Video Recensione Zeiss Dialyt 18-45x65
6 agosto 2021 di Piergiovanni Salimbeni

All'interno di Binomania.it e sul canale YouTube ho spesso descritto le prestazioni dei classici cannocchiali per uso naturalistico e venatorio. Questa volta però vorrei parlarvi di un prodotto molto specializzato che ha tre punti di forza invidiabili: robustezza, leggerezza e velocità di utilizzo. Tale strumento può essere facilmente definito come un "field spotter" o telescopio da campo.
Dear John! I thank you so much for this work!!!
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