Collimating WW2 Binoculars - A Cautionary Tale!

The first encounter I remember with my Uncle's WW2 binoculars, was at a family picnic out at an old RAF Aerodrome in Fradley, near Lichfield. These were always carried in his A35 van, in an open shelf-type compartment on the passenger's side. I never witnessed seeing them in any kind of case or cover.

WW2 Propaganda Poster

The other time I distinctly remember actually using them was at his home, when he asked me if I wanted to: "look at the tanks". With the vivid imagination of a 10 year old spurred on by the association of his time as a Desert Rat, I somehow expected to see something a lot more thrilling than the sewage containers at Bescot.

If you are wondering about these details, then it's because provenance is all with antiques and collectibles and if you know their history you can often come up with a (Sherlock) Holmsean solution to any problem. So, when I was reacquainted with these binoculars some 50 years later, I was disappointed that the view through them was not as clear as I remembered. The images through each side of the binocular were not in line and in fact they were pretty uncomfortable to use for anything more than a few seconds at a time. Seemingly, there was a collimation problem. As I have already collimated a pair of a more modern second-hand, Frank Nipole binoculars (article you can link to below), I did not see this as a problem.

In order to facilitate the collimation and also because it was a good idea anyway, I decided to make a clamp for the binoculars whereby I could attach them to my telescope tripod.

I used a plank from an untreated pallet and also a 'stringer' from the same.

Once the binoculars were mounted in the clamp, I oriented them so that I could look at a television aerial on a house roof some 80 to 100m away. It was very clear that the left-hand image was higher in the eyepiece than that of the right hand image and thus that adjustment was essential. Interestingly enough, vertical collimation errors in binoculars are the hardest for the human eye to compensate.

Unlike the other pair that I collimated (see above), the objective lenses, could not be easily rotated in their respective cells because of the design.  I was thus faced with the possibility that I would have to resort to prism adjustment and this I was loathe to do! It was at this point that I began to think of provenance, in that these binoculars which had been half way around the World, lugged across the desert and afterwards spent several decades travelling around in various vehicles without any protection before they ended in my mother's wardrobe, were incredibly clean. They also showed no signs of the external damage which are often associated with collimation. This lead me to believe that they had been cleaned on more than one occasion. I therefore wondered what the odds were that the objective lenses had been removed and mistakenly interchanged.

To test my hypothesis I set up the binoculars as if for collimation and initially began slowly to unscrew the left-hand objective lens. The images started to align. So, to determine by how much I would need to rotate the objective lens to achieve aligned images (collimation), I adhered one piece of electrical tape to the outside rim of the objective lens mount and another piece to the body of the binocular.

The collimation was achieved when the lens had been rotated almost three quarters of a turn. I could not imagine how I could fix the objective lens in this position so I continued with the premise that they had been interchanged and therefore, I unscrewed both objectives. On inspection of the inside of both I could see that the left-hand objective was more eccentrically mounted in its holder. The original collimation at time of manufacture had obviously necessitated this adjustment. Therefore, that adjustment meant that once the lens had been incorrectly swapped, the view through the binoculars would be compromised. This would not have mattered if both lenses were concentric in their respective cells.



This is a cautionary tale of a problem which I, with the advantage of having known the history of these binoculars, was able to think through before involving myself in a complicated prism adjustment. Therefore, if you purchase a pair of these World War binoculars, before you resort to any collimation do first consider that, this scenario is probably quite common!

If you have enjoyed this article and found it interesting then share it with your friends on social media or suchlike. Please also feel free to ask questions and or make comments.

Until next time and from a rainy day in Normandie,

Cheers, Andy

© Andy Colley 2018

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WW2 Poster Art Thanks to the Pinterest board of Historygallery.com

World War 1940s Binoculars - Perfect for Astronomy & Birdwatching

One of the great advantages of the heat wave this Summer has been the clear skies and absence of sea mists and with reference to fog and romance we've just returned from a trip to a Wedding in the Lake District. My wife having made her dress, my mother suggested a silk wrap she had in her own wardrobe would be the exact colours to compliment it. On a shelf below the wrap, I found my late uncle's WWII binoculars, a little battered and without a case but serviceable despite being 8th Army issue and having been lugged across the desert sands. I wondered how good they would be for astronomy, as often there are objects I'd like to view without getting out the whole telescope. Looking through the price ranges for these sturdy secondhand instruments, I now realise how suitable they are for those wanting a start in astronomy or birdwatching without the considerable layout for equipment associated with these activities.

HIDDEN TREASURE

Despite their rough and ready appearance, WWII Binocular optics were actually manufactured to a very high standard. The companies who made them saved on the casings and strappings but were required by the Armed Forces to furnish precision lenses and prisms. 

Many binoculars were actually given loaned and/or purchased from civilians, thus there were many variations in dates and makes to the standard army issue. In Britain all items were required to be marked with a broad arrow or heraldic 'pheon' by the Ministry of Supply, this to denote government ownership. In the case of my uncle's binoculars there is no such markings but then neither is there a manufacturer's mark either. In effect, as you can see in the photo below,  the company's name has been very obviously scratched off and obliterated. Similarly, I'm guessing, has the government mark! In very many cases these useful, precision instruments were repatriated with their war-time users.

Despite the missing  markings and having researched and viewed a whole panoply of fabulous vintage binoculars from around the World, my guess is these are Kershaw of Leeds standard issue binoculars 6 x 30 known as the No 2 MkII. However, as the optical information is positioned differently to that of all the rest I have seen (below rather than above the removed manufacturer's mark) I am still open to suggestions.

Look for these binoculars online or at yard sales and car boots. They regularly turn up on ebay and in Military forums and shops. With regards to Kershaw, there is a great article (link below) on  stargazerslounge which provides useful details on this particular make.

Left:  A British Intelligence Officer with his Kershaw's No2 MkII.

BUILD QUALITY OF OPTICS & MATERIALS

The army issue binoculars of this period, in almost every case, use uncoated optics. Nowadays all optics are given several coatings to improve image quality. However, from my initial views through these binoculars, I can testify that the image quality is sharp across almost all the field of view and fringing is undetectable. The reason for this is the basic optical quality of the glass used prior to WWII. 

The Bakelite eyecups, which have an integral threaded brass bush within them, are an example of good engineering practice. Nowadays binoculars in this price range and above have plastic threading, which is prone to stripping if not correctly engaged.

Another bonus I have discovered, is the individual focus of the binoculars, a design used prior and during the war due to ease of manufacture, robustness and waterproofing. Central focus was a selling point of the post war period but it brought with it several problems, not the least of which was it being the first component to fail, particularly, in my experience, on compact binoculars. I remember trying a pair of pricey, secondhand binoculars with central focusing in a Birmingham camera shop only to find that the focusing linkage was broken!

Ordinarily cheap binoculars do not have good eye relief, aka the distance from the eyepiece to the eye. This is because manufactures focus on magnification ("power") as a major selling point.  Due to the optics of the 6 x 30, eye relief is so good that the binoculars can be used even when wearing spectacles. Poor eye relief means that the binoculars must be held right up to the eye which can become very uncomfortable for stargazing or bird watching.

 

WHAT TO LOOK FOR WHEN BUYING

Standard issue WW2 binoculars can be purchased for as little as single figures and many of the problems/injuries they have incurred over time are repairable. However, I would always consider the price in light of any potential labour involved and maybe pay a little more for a better pair. There were several manufacturers who made military binoculars and it is a good idea to view as many pairs as possible and get a good idea of the current market prices and values. This said, it can be very satisfying to give these great pieces of optical engineering a second life.

MOULD - in particular if the binoculars do not include a case, you should be aware of the fact that mould spores can enter and begin to colonise a lens when it has been kept in damp conditions. There are things you can do to control the spread of this, such as the use of UV light but it is something you should be aware of and decide if the price has been adjusted accordingly. HEAVY MOULD however should be avoided. Colonies of mould can actually etch the glass of the lens, causing damage which will need expert and costly repair.

DAMAGED LENS ELEMENTS - this occurs with the age of the instrument, the cement joining two lens elements deteriorates. However, solutions exist whereby the lens elements can be separated, cleaned and re-glued. Again consider this in relation to the asking price.

OUTGASSING -  the oil and grease within the casing of the binoculars can sometimes deteriorate with age causing a process known as outgassing which can leave a deposit or film on the optics and housing. This will show up as a misting or hazing when the binocular is used, resulting in a loss of contrast. It is often difficult and costly to repair.

CRACKED OR BROKEN LENSES OR PRISMS - I would only consider these for spares and repairs. It is sometimes both practical and certainly economical to buy a couple of damaged pairs and make one good serviceable one!

GENERAL APPEARANCE & MECHANICAL FUNCTION - Given that most of these binoculars were manufactured for years of War Service, envisaging various climates and environments they are built for robustness and not looks. Do not be put off purchasing due to a shabby or paint-chipped exterior. This is to be expected as these items have quite literally 'been through the wars'. However, there are certain elements which are crucial if you are going to want to use these in the field. Here is a short checklist of what I look for:

Central Hinge is not loose,
Focussing Mechanism is smooth,

Denting to body is superficial and nothing that could indicate interior damage or initiate further problems.

Cleanliness of Optics - although a certain amount of dust and grime is to be expected and can with care be removed, highly contaminated lenses may mean poor storage and are perhaps indicative of further and more serious neglect.

Indications of Cleaning - be aware that an inexperienced seller may have 'cleaned' the optics prior to offering for sale. Unless done with care, this process can have caused more harm than good, resulting in scratched or damaged optics. In effect there is a school of thought that believes that dust actually makes little difference to viewing and that it is better to purchase those binoculars that show honest use rather than a last minute pamper.

Indications of Bad DIY - get a feel for what the exact model or make of binoculars should look like and be aware of additions in the way of screws, nuts and bolts that indicate the binoculars have been taken apart or missing parts have been replaced with inappropriate substitutes. At the same time, you should also consider that some repairs may have been made 'in the field' and with care. These interventions, like those to antique furniture, can be classed as 'honest repairs' and reinforce the premise that these were/are excellent instruments and well worth restoring. 

Indications of Repainting - as already discussed the body of the binoculars unless badly dented/damaged has no impact on the quality of the optics. However, repainting the body can cause many of the working and/or removable parts to become sealed and inoperative. Personally I would avoid heavily repainted pairs of binoculars, removing this sort of paint from joints is a difficult operation. However, if the binoculars are fully functioning and the price is low enough, I would reconsider. 

Collimation - this is when the optics in each side of the binocular are misaligned resulting in two images being seen rather than one. The degree of misalignment can be slight to excessive and if the former is the case then you may be able to use them as is but you will rapidly get eye strain. However, the Recollimation of binoculars is not impossible and you may be able to pick up a bargain even in high end WWI or II binoculars with this fault. In the next article I will look at my own WWII binoculars as a case study, which will include recollimation.

IDEAS FOR REFERENCE BOOKS

There are some really excellent books for binocular and small telescope astronomy and one of my favourites is 'Turn Left At Orion' by  Guy Consolmagno and Dan Davis. This provides the novice astronomer with a great introduction to many striking celestial objects in a simple, clear way. It's a book I still go back to for reference after many years of observing the skies.

Another choice for me would be, "Binocular Highlights" by Gary Seronik, as a great manual for observing the night sky and again accessible to both the beginner and experienced astronomer.

I also have a great fondness for and appreciation of the books of Patrick Moore and own several authored by him. Binocular Astronomy is in the Patrick Moore Series was written by Stephen Tonkin, who I know from his excellent works 'Amateur Telescope Making', these books too are well worth checking out.

I would further suggest buying these books in the 'spiral' version (where available) as they will get constant use and are more robust in this format.

Please feel free to share this article, comment and/or ask for further information.

Until next time!

Cheers, Andy

© Andy Colley 2018

RELATED ARTICLES

Collimating World War 2 Binoculars

Unlike the more modern pair I collimated, the objective lenses on these could not be easily rotated in their respective cells.  I was thus faced with the possibility that I would have to resort to prism adjustment and this I was loathe to do! It was at this point...read more

Ref: Link to Stargazerslounge article here

Thanks to Hubpages of Briseham for the WW2 Poster and Tales from the Supply Depot Blog for the photo of the British Intelligence Officer