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PROPERTIES AND PERFORMANCE OF THE NEW LEICA TRINOVID 7X35B (=HERE NAMED RETROVID) COMPARED WITH OLDER LEITZ-LEICA TRINOVIDS AND WITH BINOCULARS FROM BECK, FOTON AND THE NEW KOWA 6,5X32.γFEBRUARI 2020
Dr. Gijs van Ginkel
INTRODUCTION.
In 1953 Leitz filed a patent request for a roof prism binocular with a remarkable design: a roof prism
and two mirrors. Another remarkable feature was the focussing wheel with a built-in diopter
adjustment and a fully internal focussing system to prevent intrusion of dust and moisture into the
binocular body. Because of these three new features this new binocular was named TRINOVID from
TR=three, NOV= novelties and VID= video=see. Two models were made: 7x42 (FOV170m/1000m)
and 8x40 (FOV 80m/1000m). It was the Trinovid-1 series launched in 1958. Not very many were
made for different reasons among others because of the high price and because of the complicated
repair proces.
In 1963 Leitz introduced a new range of Trinovid binoculars: the Trinovid-2 series with the models
6x24, 8x32 and 10x40.
β THE 7X35B LEITZ TRINOVID-2
This Trinovid-2 range was in May 1965 extended with the introduction of the 7x35B Trinovid, the
first Leitz binocular with roll-down rubber eyecups to give spectacle users better access to the whole
field of view.
At the end of the seventies production of the 7x35B was stopped, but started again around 1982
because of the many requests from customers for this binocular, so Leitz restarted production of the
binoculars again in the time period 1982-1988. Around 2016-2017 Leica developed plans to restart
production of the Trinovid-2 series 7x35, 8x40 and 10x40. It took until 2019 until they came in limited
amounts available and that only in special Leica shops, not in regular binocular shops.
In this paper we have investigated three original 7x35B Trinovids from 1966, 1982 and 1986
respectively. The performance of these binoculars was compared with the new Leica Trinovid 7x35 B,
here indicated as the Leica Retrovid 7x35B based on a proposal on the WEB-site Birdforum to use this
name for the new Trinovids.
Figure 1. From left to right: Leitz Trinovid 7x35B (1966), Leitz trinovid 7x35B (1982, Leitz Trinovid
7x35 BA (1986) and Leica Retrovid 7x35BA (2020)
The new 7x35B Retrovid (as well as the 8x40 and 10x40 Retrovids) does not have roll down rubber
eyecups, but eyecups that can be pulled out/pushed in, a construction also used in other binoculars, see
figure 1. Two less known roof prism binoculars were also included in the test: The Beck Diorit 8x30
and the Russian Foton 7x35. N.B. The Leitz Trinovids were all optically except for the 7x35B from
1966. This binocular was not perfectly clean inside, hardly visible, but it affects light transmission, as
shown by the measured very low light transmission. Cleaning will undoubtedly help, but we did not do
that since it shows the possible problems when buying used binoculars.
The original Leitz Trinovids had Uppendahl roof prisms, whereas the new Leica Retrovids were
supplied with Schmidt-Pechan roof prisms. Both prisms have six reflective surfaces and in both prisms
one of the surfaces has to be supplied with a reflecting mirror to avoid light losses due to non-perfect
reflections on that surface. Nowadays these reflective mirrors consist of di-electric coating materials,
which are very effective and not sensitive to oxidation etc. like the silver coatings, see Figure 2.
Figure 2. Schmidt-Pechan Roof prism (left) and Uppendahl roof prism (right). The mirror surfaces are
indicated (Figure from Dr. Seeger, βFeldstecher. Fernglaeser im Wandel der Zeitβ, Bresser, 1989)
β Beck Diorit 8x30 and Foton 7x35.
For those not familiar with Beck: The company Christoph Beck & SΓΆhne (CBS) started in March 1892
in Kassel. The company made among others binoculars and microscopes of excellent quality.
Especially the TORDALK 11X80 and 22X80 binoculars were highly valued by users. The binocular
program consisted mainly of different types of binoculars with porro-prisms, but for a short time also
two roof prism binoculars were produced: the Beck Diorit 7x35 and 8x30. They are well made with a
specific design. We had only the Diorit 8x30 available for this test. Since I had no information about
the year of production of the Diorits, I guessed the year of production as 1973, but it seems more
likely that it is produced around 1965. The Russian Foton binoculars look a bit like the East German
Zeiss Notarem binoculars, but I did not check that in depth. Two different Foton models were made: a
7x35 and a 10x40. The Foton 7x35 is tested here. It is reported to be waterproof, but we did not
investigate that.
Figure below: left Beck Diorit 8x30, right Foton 7x35.
β COMPACT LEITZ-LEICA TRINOVIDS/ULTRAVIDS.
Figure 4. From left to right: Leitz Trinovid 8x20C (1978), Leica Trinovid 8x20BC (1998), Leica
Ultravid 8x20 (2004) and Kowa 6,5x32 (2019).
β THE LEITZ-LEICA COMPACT TRINOVIDS AND THE ULTRAVID.
In the beginning of the nineteen seventies the Leitz design team developed some protoypes for a series
of new compact binoculars. Production of it started in 1974 with the models 8x20C and 10x22 C,
where C stands for Compact. The binoculars had internal focusing and a diopter adjustment control
around the right-side eyepiece. The first ones had hard eyecups (an example is tested here) but later
designs had pull out-push in eyecups (the Trinovid BC series). The binoculars were showerproof but
not completely water tight. In the BC Trinovids the right eye diopter control was moved from the
eyepiece to a new position around the objective barrel, see the Titanium Trinovid BC from 1998
investigated here.
N.B. Because of the measured low light transmission of the Leitz 8x20C it was carefully inspected
over and over, but we did not observe pollution of the internal optical system.
In the beginning of the new millenium Leica introduced another compact line: the Ultravids 8x20 and
10x25. These compacts have an internal focussing system and a completely new body design, see
figure 4. The Ultravid minis can also be considered as excellent quality compacts.
- KOWA 6,5X32: A REMARKABLE COMPACT BINOCULAR
In 2019 Kowa introduced an attractive compact binocular with a large field of view: the Kowa BD II-
32 6,5X32 XD. In figure 4 above this binocular is shown to the far right. Its performances are
investigated here also, see table 2 and the transmission graphs. The binocular offers attractive features
like a large field of view, a short close focusing distance, lower magnification for good observation
stability, handling comfort all right, although the strap rings may fit close in the palm of the hand and
that can be painful. The price is attractive.
Figure 5. Schematic cut away from a Leitz Trinovid (left) and a porro prism binocular (right)
Figure 6. Schematic drawing of a Leica Retrovid eyepiece.
Figure 7. Scheme of a Leitz Trinovid eyepiece (from an old Leitz flyer).
CONCLUSIONS.
-1- The Leica/Leitz compacts.
- The Leitz 8x20 C from 1978 is still in the present time an attractive binocular, easy to handle and with a good optical
quality except for the fairly low light transmission.
- The Leica Trinovid 8x20BC Titanium from 1998 is a very nice compact binocular, with good handling comfort and
very good optical quality.
- The Leica Ultravid 8x20 can be considered as one of the best compact binoculars on the market: excellent handling
comfort and with a very high optical quality.
-2- The new Leica Retrovid 7x35B is as far as body construction/appearance is concerned a perfect copy of the
beautiful original Leitz/Leica Trinovids 7x35B from the sixties-seventies and eighties, but it now has pull-push
eyecups which is more attractive than the original foldable rubber eyecups. Handling comfort is excellent just like the
original Trinovids. The original 7x35B Trinovids had a larger field of view, whereas the Leica Retrovid has 8-9%
higher light transmission over the whole measured spectrum which yields a brighter image. Both the old Trinovids as
the Retrovid show minor remnants of color dispersion.
Personally I prefer the original Leitz-Leica Trinovid of the most recent production of 1982-1986 over the new Leica
Retrovid from 2019-2020 because of the slightly larger field of view.
-3- The Beck Diorit 8x30 and the Foton 7x35 are interesting binoculars certainly from a collectors point of view. With
regard to user comfort and optical quality they stay behind as compared to the most modern roof prism binoculars.
Nevertheless, they are still useful binoculars for users with a low budget.
-4- The Kowa BD II-32 6,5x32 XD is for its price of 399 euros an excellent binocular: compact with good handling
comfort, good optical quality and rock steady image quality due to its lower magnification of 6x (we could not confirm
6,5x). Especially its large field of view, short close focus and bright image quality (high light transmission in
combination with a 5,3 mm exit pupil) makes this a very attractive instrument. The only disadvantage is the
placement of the lugs for the carrying strap, which can be rather painful when using the binocular, since they fall in
the most sensitive part of the hands.
Acknowledgments: I am grateful to Ing. Dave van den Heuvel for his efforts to realize the presented transmission spectra
and to Jan van Daalen, House of Outdoor (
www.houseofoutdoor.com) and some other collectors for the supply of different
binoculars for this test.
BECK BINOCULARS
Below: Flyer of Beck binoculars also containing the technical data of the two Diorit models that were made
by Beck. As far as I know these are the only roof prism binoculars made by Beck. The company however did
have a large production programme of porro prism binoculars.
Different models listed in other Beck flyers are for example: Beck Merkur mini 8x20, three different types
of 8x30 binoculars from which the 8x30W is remarkable with its FOV of 175m/1000m.
Two types of Beck Merkur 8x40, the 8x40W with FOV of 158m/1000m, three different Merkur 7x50 mod-
els, the Merkur 8x56, 10x40 and two Merkur 10x50 models.
Another Beck flyer lists the: Kolibri 4,5x20 (FOV 175m/1000m), Kobold 7x20, Zenith 8x30, Stern 8x32,
Diana 8x40, Condor 8x45, Diana 8x40W, Luchs 7x50, Saturn 15x60, Merkur 20x60, Comes 30x60, Tor-
dalk 11x80, Planet 22x80, Ozelot 8x30, Avus 8x30W, Jagdfalke 7x50, Jagdfalke 10x50, Hogla 8x56 and
Hogla 10x56
This is only a review of two Beck flyers, which makes it clear that Beck was at that moment in time an im-
portant player in the German binocular world.
TABLE 1
BINOCULAR LEITZ TRINOVID
COMPACT 8X20C (1978)
LEICA TRINOVID
COMPACT 8X20 BC (1998)
LEICA ULTRAVID 8X20
(2004)
Weight 180 g 228 g 243
Prism type Uppendahl roof Uppendahl roof Uppendahl roof
Diameter objective
O
20,9 mm 19,95 mm 20,0 mm
Diameter exit pupil
P
2,45 mm 2,65 mm 2,6 mm
Magnification
M=O/P
8,5x 7,5x 7,7x
Eye relief (mm) 8 mm 17 mm 16 mm
Field of view
(m/1000m)
120m 115 m 110m
Close focus (m) 2m 2,6 m 1,6m
Eye distance
beween both tubes
32-80 mm 32-80 mm 36-74 mm
Revolutions close
focus to infinity
3,7 2 2
Transmission
500 nm
550 nm
54%
56%
85%
86%
92%
94%
Revolutions close
focus to infinity
3,7 2 2
Color reproduction ok ok good
Diopter
compensation
+/- 3,5 dpt +/- 3,5 dpt +/- 3,5 dpt
Phase coating no yes yes
Authors judgment + ++++ +++++
Price (euro)
opinion of the
author
25-75 euro 100-200 euro 500 euro
TABLE 2
BINOCULAR LEITZ
TRINOVID
7X35B (1966)
LEITZ
TRINOVID
7X35B
(1982)
LEITZ
TRINOVID
7X35BA
(1986)
LEICA
RETROVID
7X35B
(2020)
BECK
DIORIT
8x30 (1973)
FOTON
7X35
KOWA BD-
II32
6,5X32XD
Weight (g) 535 g 523 g 586 g 572 g 485 g 488 g 528 g
Prism type Uppendahl
roof
Uppendahl
roof
Uppendahl
roof
Schmidt-
Pechan roof
Schmidt-
Pechan roof
Schmidt-
Pechan roof
Schmidt
Pechan roof
Diameter
objective (O)
34,6 mm 34,7 mm 35,6 mm 34,6 mm 29,5mm 34,8 mm 31,75 mm
Diameter exit
pupil (P)
4,8 mm 4,7 mm 4,8 mm 5 mm 3,9 mm 4,8 mm 5,3 mm
Magnification
M=O/P
7,2x 7,4x 7,4x 6,9x 7,6x 7,3x 6x
Eye relief
(mm)
13 mm 15 mm 16 mm 17 mm 12 mm 12 mm 20 mm
Field of view
(m/1000m)
150m/1000m 150m/1000m 150m/1000m 140m/1000m 130m/1000 m 150m/1000m 175m/1000m
Close focus
(m)
5,5 m 5,5 m 6 m 4,2 m 6 m 6,5 m 1,1 m
Eye distance
between both
tubes
56-76 mm 56-75 mm 56-76 mm 55-76 mm 57-74 mm 53-74 mm 55-75 mm
Transmission
(N.B.)
500 nm
550 nm
Left Right
37% 49,3%
41% 57%
81,2%
84,5%
81,2%
84,5%
90%
92%
61%
63%
68,5%
69%
90%
90%
Revolutions
close focus to
infinity
2,1 2 2 2 0,8 1,5 1,4
Color
reproduction
ok ok ok good ok Slightly
yellow
good
Diopter
compensation
+/- 3 dpt +/- 3 dpt +/- 3 dpt +/- 3 dpt ? +/- 5 dpt? +/- 3 dpt
Phase coating no no no yes no no yes
Authors
judgment
+ ++++ ++++ ++++ + + ++++++
Price (euros) 50-100 300-500 300-500 1400 50-100 30-75 400
N.B. Older binoculars may suffer from loss of transmission due to impurities in the optical system, as
an example see the spectra of the two Leitz Trinovid tubes from 1966; the left one has a tiny optical
unclarity in the optical path, the right tube does not and that yields a 12-15% transmission loss.
Visually it is even difficult to observe.
