Bill Reid has a new paper on Barr & Stroud, and a letter expanding on an earlier article, in the new Bulletin of the Scientific Instrument Society:
Reid, William. Barr & Stroud 'Nitrogen-filled Binoculars': the facts. Bulletin of the Scientific Instrument Society No. 81 (2004) 34-36.
(the inlet into the prism housing is for use with a dessicator, not for nitrogen purging)
A letter on pp18-19 expands briefly on his:
Binoculars in the Air. Bulletin of the Scientific Instrument Society #70 (2001) 19-27.
Among other details, there are more hints on the rejection by the British of 6 x 30's by B & L and Crown, about 80 years ago. The exact reasons for this rejection are buried in British archives, but would be quite interesting to learn.
>>>When I did find collimation errors, I would pull the hinge, and replace one side with another until the error was down to a degree (or two).
Finding perfection (< 1 degree off) was pretty much illusive, so there really is some point of no return with this glass. But, I am sure that some of the OM's out there might have special tricks and techniques to rectify the impossible.<<<
Trick # 1: OMs in the fleet revered to Steiner's as disposable binoculars. And, of course, that is the mentality that closed the school in 1999 and did away with the OM rate in 2000.
Trick #2: know that when the BOOK says 2 minutes of step and 4 minutes of spread, it did not DEGREES! Although the hides of OMs who tried to collimate to DEGREES instead of minutes did make dandy lamp shades . . . especially those with interesting tatoos.
Trick #3: Realize that anything is easier to do in a production setting, where you are producing hundreds of identical prism clusters at the same time. The problems with the MK 22 can be overcome effectively. BUT, only by those who a) do not have a life, or B) who consider their time worth much less than minimum wage, or c) who think a collimator is a cross between a collie and an alligator.
Just a thought.
Bill Cook, OMC USNR-Ret.
Subject: Nikon marks
Nikon dropped the Nippon Kogaku markings from their Nikon F cameras around 1967. They seemed to have dropped the marking from their binoculars and marked just Nikon at about the same period.
> I have just bought two Japanese binoculars issued by the Swedish navy.
The M-22's were made in several large production runs. Many of the early units (as far back as the Seeadler-Opik models) were made in the glued version. While it is minutely cheaper to manufacture and a more secure seal with this version, it also made it very difficult for the factory to make any production line corrections or minor warranty repairs. We developed a number of special tools and procedures to work on both versions, but as has been mentioned, even with these advantages, some of the glued version can be very difficult, if not uneconomical to repair. As far as the nitrogen leakage goes, Steve is quite right, the gas will stay inside for a while, but the focusing action and thermal cycles do let the gas escape. The biggest effect of the N2 is that it initially purges the air and moisture out of the instrument and gives it a head start against hostile environmental conditions. It is a fully o-ringed binocular, and as such tends to stay fairly water and dirt resistant under normal conditions. Collimation does tend to stay in place unless a prism shifts. We still work on a fair number of them each year of both commercial and military models.
Again we will say how pleased we are with the list.
Here some clues on earlier questions.
regards, BjÃrn Nyman, Sweden
With references to binocular list no 101 April 24, 2000.
My object of a Mirakel binocular, has the name on the right hand housing and on the left hand housing is Marwix, Berlin.Not any serial number.
The dimensions is 96 mm broad and length is 64 mm. Weight is 158 grams.
On the brass washer at the top center of the hing, the magnification is given 5X and cross the script is 65, wich means the focal length of object glasses and diameter 15,5 mm.
Sold by a Swedish optican AB CL Fritze, established 1837.
The label is a goldprint, with a crown on the top of the lead of the leather box.
With references to binocular list no 300.
Nikon military issued for Sweden
Friend Robert Forslund question about Japanese binoculars. Maybe I can give some further informations or light over the case. In our collection we have some similar.
One "Nippon Kogaku" binocular 7x50 7,3â–« field of wiew, serial number 804795, Right top cover with triple crowns and Nippon Kogaku Tokyo. JB-7.
On the left top cover 7x50, 7,3â–« Coated Swedish military typenumber M 3011-191001.
No. 346/67. The last two figures may mean year 1967. The top covers are fastened with five screws. No rubber protection.
One another similar with serialnumber 805343 JB-7. Swedish military typenumber on a glued signplate M3011-191030. No rubber armouring.
(I have a picture of a binocular of the same type nr 804607. No rubber armouring. )
The last one mark "Nikon" on the left top plate 7x50 7,3â–«. Right top cover triple crown glued on a sign plate M3011-191032-2. Serial number 865215. Totally rubber armoured. The top covers are fastened with five screws.
In the collection we also have two older 7x50, japanese binoculars issued for military use. They are traditionally build as a "Zeiss Binoctar". Made by Micron. Number 741098 and 742382. Swedish marking Ã–VG. Means Ãrlogsvarvet GÃteborg. (navy shipyard Gothenbourg)
The name was taken away 1964, and changed to "Ã–rlogsbas vÃ¤st" = Marine base west.
Thank you for the details on Swedish binoculars. Email does strange things to the Swedish alphabet, I don't seem to be able to fix that.
In the current issue of 'TIME' magazine, dated June 28, 2004, page 74 there is a news item - not an ad - describing Bushnell's binocular and digital recording instrument. It is listed among the recent technical advances.
CZJ Catalogue online (From the Deutsche Optik bulletin board)
Posted by Holger Merlitz on 06/21/04
I have scanned one CZJ Catalogue of about 1985, a copy of which Gary Hawkins had kindly sent to me. The scans can be found here: http://www.geocities.com/holger_merlitz/czj_85/czj_85.html
I would like to encourage more readers of this forum to do the same: If you have got one interesting historical document, put it online and share it with us! If you haven't got the technical facilities, you may consider to take a hardcopy and send it to me and I will scan it and put it online (but I will have limited space on my disk, of course). Maybe, over the years we will be able to set up a database of otherwise hard to find historical documents. With best regards, Holger
Here is Holger's home page, with a list of all his reviews:
Kronos BPWC2 6x30 binocular review
Review: NVA DF 7x40 vs. BPO 7x30 vs. Kronos BPWC 8x40
Review: Nobilem 8x50 B/GA vs. Jenoptem 7x50W vs. NVA DF 7x40
Review: NVA EDF 7x40 vs. BPO 7x30 vs. Hensoldt DF 8x30
Review: Fujinon 10x50 FMTR-SX vs. Docter Nobilem 10x50 B/GA vs. Zeiss Jenoptem 10x50W
Application profiles for hand-held binoculars
Review: Docter 10x42 B/CF vs. TS 10x42 vs. Zeiss Dialyt 10x40 B
Review: Zeiss Dienstglas 8x30 vs. Hensoldt DF 8x30 vs. Steiner Fero-D 12 8x30
Review: IOR-SA 7x40 vs. Zeiss Jena EDF 7x40 vs. PZO 7x45
How to identify faked Zeiss Jenoptems, with materials by Claudio Manetti
Review: 10x50 Swift Kestrel vs. Zeiss Jenoptem vs. Hensoldt Diagon
Review: Nikon 8x32 SE vs. Fujinon 8x30 FMTR-SX vs. Hensoldt 8x30 Fero-D 16
NEW: Carl Zeiss Jena catalogue of 1985
......and there is a link to these interesting diagrams from Zeiss:
It has been very quiet lately, which is ok, though we welcome contributions. The Deutsche Optik forum has been on an even keel lately, after some unmoderated moments when too much was said; and there are other forums for active exchange of email on old binoculars. But I'll send out more frequent lists with a bit more email. There are some very well informed persons who receive this list & will answer questions if prompted.
Subject: Images posted to web
.....some pictures of the Canadian REL binocular with the carousel filter, posted at this URL:
List member Gary Hawkins has some very nicely photographed images of unusual binoculars:
......including a Leitz 'Apollo-glas'. Is this a model used on the Apollo missions?
"For Wally Schirra's Apollo 7 mission of Oct. 1968, a Leitz 10x40 spotting scope was used for visual observation, as well as in the Apollo 9 mission of March 1969.
In May & June of 1973, Skylab 2 was equipped with a Leitz Trinovid 10x40 binocular, modified for use in space, and with Hasselblad & Nikon cameras. The same equipment was carried in Skylab 3, July-Sept. 1973; Skylab 4, Nov. 1973 - Feb. 1974; and the Apollo-Soyuz Test Project of July 1975." --from a paper I wrote on telescopes in space.
Subject: Night fighters of WWII......any with binoculars?
From: Peter Abrahams
I have been reading: J.E. Johnson. Full Circle: The tactics of air fighting 1914-1964. N.Y.: Ballantine, 1964.
Johnson was a British military pilot. The first chapters include many excellent stories about WWI aircraft, fighting strategy, and the formal courtesies the pilots gave their enemy counterparts.
As WWII began, military aircraft were mainly limited to daytime use, and the development of nighttime capability was crucial to the war effort. Most of this effort was directed towards equipping airplanes with radar.
Fighter aircraft for use at night included the U.S. P-61 Black Widow night fighter, with a specialized 6x42 binocular, recently discussed on the list by Fan Tao. Other forces developed night fighters, and the question is, whether any of these were equipped with binoculars. Britain, Germany, Japan, Russia, and the U.S. used night fighters. Perhaps a listing of known night fighters would be a good way to start a search for specialized binoculars they might have had as equipment.
There are many aircraft that were designated 'night fighter'. The main point was made in one site: in the "desperate need for anything that would fly at night", many unsuitable adaptations were made.
Some of the below is taken from web sites, which inevitably include some errors. I personally welcome corrections but don't want to turn this list into an aircraft list, so barring any objections I'll only distribute email about binoculars.
There is a very good essay on night fighters of Finland during WWII: http://www.sci.fi/~fta/nightftr.htm They used Brewster, & Messerschmitt 109 G-6, airplanes in defense against Russian bombers. (An unusual strategy was to have Finnish bombers join the Soviet bomber formations as they returned home over the Gulf of Finland, and then bomb the Soviet air bases while the Russian bombers were landing.)
Johnson, p178. British aircraft adapted for use in night fighting included the Blenheim, the Beaufighter, the Defiant, and the Hurricane. Some of these "were transferred to night fighting not because the aeroplane was suitable, but because it could not exist by day."
1944, Mosquito night-fighters equipped with radar. http://www.raf.mod.uk/history/line1944.html
Defiant, Beaufighter, Mosquito, and American A-20, aircraft flown by the RAF. USAAF units acquired and operated the British Beaufighter, and later the Mosquito, successfully in the European theater. http://www.wpafb.af.mil/museum/history/wwii/nf.htm
The British took the U.S. attack bomber Douglas A-20 Boston attack bomber, & adapted it to the Havoc, a night fighter, with radar; equipped with a searchlight, known as the Turbinlite
Canada sent RCAF night fighter pilots to Britain; as did New Zealand.
Johnson, p212. 1940, Dusseldorf, experimental unit of Messerschmitt 110 airplanes, developed a night fighter model. Junkers 88 specialized as a night fighter.
Germany: HE-219 Owl; Focke-Wulf Fw 190
Junkers Ju 88C-6c; Junkers Ju 88G-1; Junkers Ju 88G-7b
Nakajima C6N1-S Night Fighter Saiun(MyRT)
Ki-45 Toryu (U.S. name: Nick)
night fighter J1N1-S Gekko (Moonlight). later version, J1N1-Sa Night Fighter Gekko. (U.S. name: Irving)
Japanese Navy, WWII, IJN Night Fighter Aircraft S1A1, manufactured by Aichi, official name: Navy Experimental 18-Shi Hei (C); Type Night Fighter Denko
Johnson, p241. Russia began a night fighter force by equipping day fighters with flares and searchlights.
In addition to the P-61, the first US aircraft designed & built as a night fighter:
The Marines used specially equipped F6F Hellcats as night fighters.
The USAAF also used the British Beaufighter & Mosquito in Europe
In the Pacific, the USAAF used the P-70 version of the Douglas A-20, and the P-38, until the P-61 was available.
The Havoc, the night version of the Douglas Boston attack bomber; equipped with radar, known as the P-70.
F4U2 Corsair, converted from the F4U1 by adding radar.
Night fighter versions of the Grumman Wildcat & the Grumman Tigercat.
Grumman F6F Hellcat, night fighter version F6F-5N, very successful
I heard from Kevin Kuhne, who sent images of a previously unknown Zeiss model. It is marked blc 20x80; in a heavy Porro II body. Coated optics, wide angle, performance breathtaking, of a type not seen before. Kevin asks if anyone has seen or heard of these before. Images:
The site is not yet finnished but there is plenty of pictures of items and there is also little text written and I am continuesly writing more ..........
Please comment back what you think.'
These are very nicely photographed. Some interesting notes:
'Zeiss 7x50B......Those are currently used both in the army and the navy.'
'Nietche 08', a Galilean 08.....possibly Nitsche & Guenther, Rathenow, code 'gxh', found on gunsights?
Inscription on this Goerz 6x30; 'WBA Mit Skala M9'
My family and I just returned from a trip to Yellowstone and Teton Parks and I made some informal binocular related observations. I was struck by the number of people with full sized Porro glasses. Most were the usual Bushnell-but also Pentax and equivilent quality optics. In fact, the small inexpensive 8 and 10x25 roofs seemed mostly carried by the kids!! On the other hand-high end optics other than occasional older Nikons were rarely seen. (This in obvious distinction to my visits to sites frequented by birders and serious, albeit amateur, naturalists who favored Zeiss classics, some Leicas and many Swarovskis.) The in Park stores sold Bushnell, Pentax and some Simmonds. My crew carried a mixed bag whose field performance was intersting. The Olympus Magellen 8x42 roof, phase coated, waterproof-picked up on the 'Bay as a factory reconditioned glass for about $100 was outstanding! Bright, no distortion, good field, edge to edge clarity, easy to handle and compact. A first class field glass that you don't have to worry about. At least 90+% as good as my Leica at 1/8 the cost. A Minox 10x25 reverse Porro was disappointing-not very bright even in full sun, good edge to edge but not overall sharp with fair color rendition-about what one would expect from a middling Asian effort (which is exactly what I think it is despite it's immediate German origins.) My old Russian Foton 7x35 came thru again-very light weight, bright, excellent color and phenomenal central sharpness and clarity but trails off a bit at the margins. Mechanics OK-must keep fiddling with the focus despite the good depth of field. Near focus not nearly as good as the Olympus. Not waterproof. Next, a fun little piece-a chinese Turmon copy-NC Star-10x25 picked up at a gun show for $10!! Narrow field, a bit dark, centrally sharp but trails off quickly. Mechanics surprisingly good-but always with you, unobtrusively-best for quick glances- Once you figure out how to hold it properly given the 0 eye relief!! Lastly, tied for first place was a Canon 10x30 image stabilized glass-also a factory reconditioned offering. Despite its geometry it is amazingly bright, sharp edge to edge with terrific cental sharpness-perfect color rendition. The IS system has its limits-not much help on the boats or rafts-but great when trying to see details at range. The 10x is very helpfull at the ranges encountered here out West. At Jackson Hole spotted 9 Moose in 30 min with this glass. Very good close focus as well. My wife preferred the Olympus because of the screw in eyecups and great eye relief as she wears glasses. I preferred the Canon-only drawback was the added weight and my concerns about possible fragility-perhaps unfounded. As I said, nothing technical or profound-but some every day binoc observations.
In 1892, Ernst Abbe was contacted by Hector de Grousilliers, an engineer in Berlin, who had working drawings of a new range finder for artillery observers, using enhanced depth perception to estimate distance. H. von Helmholz and August Kundt had told de Grousilliers that this was not a practical idea, but Kundt referred him to Abbe. Helmholz had earlier proposed a non-magnifying telestereoscope, using mirrors. Abbe and de Grousilliers worked in autumn of 1892, and together developed the Relief-Fernrohre, in the 'scissor' configuration; and the Stangen-Fernrohre, in the solid tube configuration. Abbe's patent application of July 1893 was rejected because of Porro's earlier work, but a patent of 9 August 1894 was granted for an optical instrument with increased separation between objectives. Military sales were expedited by de Grousillier's association with German military personnel.
Hector de Grousilliers seems to have been a very influential person; but there is little or nothing about him in the references.
This comes from page 278 of a thesis on Zeiss, that has few details on binoculars. Feffer cites correspondence of Abbe on this associetion.
Feffer, Stuart M. Microscopes to Muitions: Ernst Abbe, Carl Zeiss and the transformation of technical optics 1850-1914. PhD Dissertation, 1994, University of California, Berkeley. 341pp.
The photograph that Kevin sent you is, in my opinion, of a postwar Kowa 20x80. One just like this pictured binocular was listed on Ebay about a year ago. There was a 20x80 German WW II binocular, but that one was based on the 45 degree 10x80 Busch design.