Military binocular repairs and service, especially WW2 types.

The following pages of photos illustrate some of the military binoculars and instruments repaired by Optrep - giving an overview of the great range of our work.

For this specialised work, quotations can be given. If parts need replacing, this can be a problem but, very often, parts such as eyecups can be made and optics can be restored (recementing etc) or even replaced. Many WW2 binoculars, once restored, are of the highest quality and often unique. They can be very collectable and a pleasure to use, a case of 'beating swords into ploughshares'.

Up to a third of the military binoculars we receive have been tampered with by someone with insufficient experience, often causing much damage but in almost every case Optrep can put such binoculars back into service.

Military binoculars are always of sealed construction and are therefore suitable for nitrogen purging to prevent fogging. Optrep carry out this procedure which is superior to the old procedure of purging with dry air or the fitting of silica gel containers. We also clean and refit graticules, unless they have been ruined by surface pitting.

Most German instruments of WW2 are identified by a 'secret' code. Click here for a list

The above picture illustrates part of an outstanding private collection (somewhere in England) of binoculars and other optical instruments, mainly from WW2. This shows about a quarter of the whole collection which is displayed in national sections. Most of the instruments were overhauled by Optrep. Of course, Optrep overhaul instruments from all ages including the most modern.
A cxn (Emil Busch) 10x80 (45°) binocular.
A blc (Zeiss) 12x60 (45°) binocular. Two were often fitted to the top of large Army rangefinders and there was also a version for the Kriegsmarine. The OG hood and brow rest are hinged and the dovetail rail on top of the binocular is for an optical ‘V’ sight (so often missing). Performance is excellent.

Other examples of German WWII binoculars serviced by Optrep:

blc (Zeiss) 7x50 fixed-focus U-Boat binoculars. The removable covers permit replacement of the moisture-absorbing silica-gel. These very rugged binoculars weigh a hefty 1.8 kg. Another U-Boat binocular, this blc (Zeiss) UDF 7x50, could be left on its mounting when the boat submerged. Its very heavy construction (weight: 5 kg) enabled it to resist water pressures up to 30 atm. Such pressure would crush any other type of binocular.     blc (Zeiss) 8x60 U-Boat Commander’s binoculars (weight 2.55 kg) serviced and repaired by OptRep. Although we do not normally carry out cosmetic work, this example was so bad externally that filling and repainting was requested by the owner. This 8x60 model is known as ‘The Fat One’.     A view of another blc 8x60, illustrating the very large 33.80mm diameter eyelenses (hinged eyecups removed).     This pair of 1937 Huet (Paris) 8x50 binoculars, overhauled by Optrep, were made for the French Navy (Marine nationale). They are waterproof and heavily sealed along similar lines to the German UDF U-Boat binoculars. Made of marine bronze they weigh 6.20kg and are 235mm long (excluding the OG hoods and rubber brow rest). Features include a side knob for altering the PD and metal sealing bellows inside the eyepieces very similar to the Ross design (e.g. Ross 10x70).     An eug (Optische Prazisions Werke, Warsaw) 10x80 (20°) binocular from a Kriegsmarine warship.It has modified Porro II prism units and a simplified brow rest. The long objective hoods are hinged to facilitate external cleaning and these have hinged Bakelite flaps at the ends. There are built-in filters, the darkest for counteracting searchlights. The knob on the right side moves the complete right half horizontally to suit different eye widths and each eyepiece is focused by means of a lever. Once serviced by Optrep the binocular is purged with nitrogen and so new dessicant is not needed.     kqc (Jos. Schneider) 25x105 (45°) binoculars for aircraft identification and general observation. Earlier models (with a retractable section to the hood) had weak attachment of the OG barrels to the prism housings but this was later greatly improved.     A rare pair of blc (Zeiss) “Bibefe” 18x80 C/1 binoculars beh (Leitz) 7x50 with dessicant cartridges (OptRep fill all such sealed binoculars with nitrogen, the modern procedure).         A WW2 beh (Leitz) 8x60 which was introduced late in the war and so was not fully developed optically. Its features and construction are basically enlarged from the beh 7x50. It is 240mm long and weighs 2.026 kg.     A rare Zeiss 10x80 (80°) binocular, with filters on the right side only     1) Carl Zeiss 7x50 binoculars with filters each side linked together by an external connection. The filters comprise yellow and, against searchlight glare, dark grey. This is a special version of the Carl Zeiss 7x50H Porro II prism binoculars for use with signalling apparatus. The unit for illuminating a graticule at night is missing underneath the right side. Carl Zeiss D.F. 7x50 M (Artl. Nr. 2396) Kriegsmarine binoculars. Note the new eyecups.

We buy German World War II binoculars and large binoculars. Send us details with, if possible, a photograph, and we will make you an offer.
More interesting binoculars recently arrived at Optrep for servicing:
Japanese WWII 7.5x60 (45°) binoculars. They use a Schmidt roof prism in the body at each side. Also, each rotatable eyepiece housing utilises a rhomboid prism. Altogether, this is a complex optical system but these binoculars give an excellent performance.	A Polish (PZO) 10x80 (45°) binocular made in Warsaw between 1954 and 1979. Based on the German 10x80 (45°), it is very well engineered and has some noteworthy simplifications. There are no built-in filters.

Examples of the principal Allied hand-held binoculars of World War Two. All serviced by Optrep
Top left: 1944 Westinghouse MI5 7x50, used by the US Navy and others. Based on the original Bausch & Lomb 7x50 model. Also made with minor variations by Square D, REL of Canada, etc. Sometimes has swing-out polarising filters built into the eyecups.	Top right: Barr & Stroud CF 41 7x50 AR No: 1900A, used by the Royal Navy. Has unique built-in filters (grey, green and polarising) operated by external knobs. Some produced with telescopic OG sun shades. After 60 years or less, the cement breaks down in the prism/field lens unit in each side but Optrep can rectify this and use permanent cement.
Bottom left: Bausch & Lomb 6x30, used by the US Army. Also made by other companies.	Bottom right: 1943 Taylor-Hobson Bino Prism No.2 Mk III 6x30, used by the British Army. Similar models made by Kershaw and other companies.

The WWII Barr & Stroud CF41 7x50 binocular is a unique and very collectable instrument, still used by seafarers today, but often needing attention when nothing has been done to them since the war.	Illustrated are the prism boxes, with eyepieces, prism/field lens units and filter wheels from a CF41 binocular. These are the prism units that often need renovating and recementing.
A less-common CF41 7x50 with spray shields, one open and one closed.
This Barr &Stroud CF60 7x50 binocular is a post-war (circa 1970) simplified version of the CF41. There are no filters and the field lenses are no longer cemented to the prisms but are incorporated into the eyepieces. The Bakelite prism housings no longer exist and the only Bakelite is used for the top plates and the OG bezels. The prisms are secured in a different way to the CF41 but the method is not as good. Fewer than 30 pairs were made before the company closed down in 1972.
This Ross 5x45 Mk IV fixed-focus binocular was the type used by the RAF for maritime reconnaissance, including U-Boat spotting during WW2. A one-piece rubber eye guard normally fits across the eyepieces.
Ross Model AC.2011 10x70 binoculars (weight 3.5kg). Usually these had a full-width rubber eyeguard. One of the heaviest hand-held binoculars, it was used by look-outs on each side of a Royal Navy warship (although it is known as the ‘Captain’s sight’ binocular). Knobs under the prism housings operate filters (orange, grey, dark grey and clear) and the very deep spray/sun shields can be swung away to the sides. Sealing of the eyepieces is by internal metal bellows which have far less friction than the leather seals of the earlier Model AC.2010.
A Ross 10x70 binocular gunsight. It has built-in filters below the Porro prism units and another very dark filter unit (anti-searchlight) in front of the objectives.
This WW2 B.Z.schr.E (Binocular sight with inclined eyepieces) is a 5+10x70 (45°) Kriegsmarine binocular. One was attached to each side of a naval gun, this being a right-hand model. The rubber brow rest, bellows-type eyecups and cast, swivelling OG hood have been removed. This is a beautifully engineered instrument full of optics and bevel and spur gears and having an outstanding performance. The magnification is altered by rotation of twin Barlow lenses via gearing. The T-coated optics include very large Schmidt roof prisms, 4-lens eyepieces and various filters and graticules that can be illuminated at night. All filters and graticules can be swivelled in and out of use. This instrument weighs about 17.5 kg.
A Barr & Stroud GK5 6x42 Director binocular used by the Royal Navy during WW2 and after. It utilises Porro II prism units with plano-convex lenses cemented to the prisms on the eyepiece side. The knobs on top of the binocular operate internal yellow, grey and dark green filters via right-angle bevel gears. The knob on the right side is for eye P.D. adjustment. Two single-line graticules in the right side can be rotated separately by screws F and B underneath the block. Weighing in at 6kg, this rugged binocular has an excellent performance.
a 1942 Honeywell (Minneapolis) M17 Elbow Telescope prismatic sight used on the U.S. Army 155mm howitzer. It has a 90° eyepiece, built-in filters and can have its graticule illuminated.
A WW2 cme (Gegr. Wichmann, Berlin) prismatic telescopic sight. It was fitted by dovetail to the rear of a German machine gun and the eyepiece can swivel sideways. Tricky to service, this complex instrument incorporates a split rhomboid prism.
This WW2 Nikko 10x70 (weight 2.306kg) was used by captains and fire control officers of the Imperial Japanese Navy (IJN). The eyecups shown replaced the original, ruined rubber winged eyecups. Air-spaced object lenses are used and an interesting feature is the spring-loaded pawls that lock the eyepieces once focused.
Giving superb, wide-angle performance, this Bausch & Lomb 7x50 Mk.41 binocular weight 2.10kg) was used by the U.S.Navy in WW2. The full-width rubber eye shield that screws on to the top shoulders has been removed.
The Nikon 20x120 binocular has the OG barrels cast in one piece to give maximum rigidity, ensuring the best chance of maintaining collimation under arduous conditions.	The blc (Zeiss) 8x60 has an outstanding performance and was much favoured by commanders and captains of the Kriegsmarine.
A 1919 Carl Zeiss 8x60 wide angle binocular which was one of the first of its type. It features Porro II prism units, extendable sun shields and a graticule that can be illuminated. Weighing 3.8kg it was mounted on a tripod and has no lanyard lugs. It was mainly designed to search for aircraft at night and to direct searchlights.
The Nikon 20x120 stripped down for a full service.
Huet (Paris) 8x30 WW2 Naval binoculars.  Other sizes, up to 12x50, were also made.  They all used modified, offset Porro II prisms mounted in complex cage and platform assemblies.
Another version of the Huet (Paris) 8x30 (8°) binocular (weight 0.97kg). This one is engraved ‘Modele 1933 Type 1. Marine Nationale’. Typical French ‘thinking outside the box’.
This 1940 Huet (Paris) 12x50 binocular uses offset Porro II prism units, tricky to renovate and recement. This pair was made for the German Kriegsmarine. The eyepiece focusing rings move the eyecells in a linear motion and they are sealed using metal bellows. Filters can be pivoted in and out of the eyecups.	Typical Huet offset Porro II cemented prism units mounted in aluminium alloy cages, these for the 12x50 left, before being renovated.
A typical throughput of the larger binoculars in the Optrep workshop. Left: Soviet PNB-2 25 x 100 (45°) ‘Border Guard’ of the Cold War. Right: cxn (Emil Busch) WW2 10x80 (45°). Top Centre: kqc (Jos. Schneider) WW2 25x105 (45°).