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ACK IN the 1980s my late wife Valerie used to produce a small magazine called Camera Collectors Bulletin and later took over Photographic Collector, though this was

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nothing to do with the American publication of the same name. Valerie was an enthusiastic collector, and produced the magazine purely as an interest as the subscription barely covered the cost of production and postage. It was well received, and she had a postal subscription of about 500. The features weren’t learned and detailed research, she left that to the one-make clubs. They were snippets and chats about collectable cameras and accessories, some well-known and some obscure. She loved digging in her extensive files of old books, magazines and advertisements looking for information for these. I still have all her files, and I’ve been going through them as well as digging out similar snippets of information. I hope you enjoy them.

ROUND about 1900, George Houghton and Sons launched a roll film camera called the Vidil in the UK that had two unusual features. First, there was a clip to hold the film and stop it coming loose on the spool. Not very earth-shaking in itself, but essential I imagine for the second feature. The film wasn’t continuous, it was in sections, each one the length of a picture, and between these sections were lengths of translucent paper.
     The idea was that a door on the back of the camera could be opened, the picture composed on the translucent paper, and then a section of film wound on to make the exposure. Each section of film was perforated so that you could tear it off in the darkroom for developing. I suppose, if you were in a tearing hurry, (no pun intended) you could undo the back of the camera in a changing bag, tear off the section of film and put it in a light-tight envelope or box so it could be developed without waiting for the rest of the roll to be used up.
     I don’t know who made the special film for the Vidil. Houghton at the time didn’t make film, and most of its cameras, except the Sanderson, were imported from Germany.
     Quite recently, and quite by chance, I heard of a camera called not a Vidil, but a Vidol. The Vidol was made by a company called Lüttke, or Dr. Lüttke & Arndt, Wandsbeck, Hamburg & Berlin, to give its full title. Lüttke made a number of cameras in the 1890s and early 1900s. The Vidol was a folding roll film camera taking postcard size pictures, and its special feature was “a light-tight door on the back to enable the user to focus on the translucent sections of special Vidol film.” The coincidence is too great for Vidol film not to be the same as Ensign-Vidil film. But that still leaves open the question of who made the special Vidol film. I don’t think Lüttke made films. Perhaps the trademark of two capital Fs back to back interlaced with a capital V might give a clue?
     So why did Houghton change the name from Vidol to Vidil? And did Houghton ever import a camera on which this special feature could be used, or was the project abandoned after the original announcement? Anyone out there know the answers?

A WRITER in Camera World wrote in 1952: “There are many small cameras designed for roll films which are now unobtainable – Ensign Midgets, Ensignettes, Coronets and others, but there is no reason why any of them should be immobilised so long as 35mm film is available”.
     Even the smallest Ensignette took a film that was wider than 35mm, so you’d need a mask, or maybe be better off cutting down 120 roll film. It would also help a lot if you had two spools for these old cameras, one to wind the film on and one to wind it on to. An original backing paper would also help, but these can be faked up from current 120 backing papers.
     I recently came across a useful site on the internet, www.cosmonet.org/camera/pico_film_e.htm, that I think was translated from Japanese. It shows how to make a jig from a junk 120 camera (I’ve got several of those) to cut down 120 film to give you one 127 film and two 16mm films for sub-miniatures. I haven’t tried it, but it looks a good idea.
     Also, I’ve made paper negatives in old plate cameras by using bromide paper exposed at 5 to 10 ISO. You get a negative print when it’s developed, but this can be scanned in to a computer and inverted using a picture editing program. Alternatively, you can still get 5 by 4in sheet film from specialist professional suppliers and cut that down. In both cases you need either a cut film sheath or something to pack out the paper or film in the plate holder because they’re thinner than glass plates.
     If you’ve successfully cut down film, or adapted spools from older cameras to take a current size of film, e-mail me with details and I’ll put them in this section with acknowledgement.

That beautiful golden look on the brass fittings of Victorian cameras wasn’t, as some people suppose, a special mixture of brass alloy near to a gunmetal bronze. The colour was all in the lacquer, as you’ll find out if you strip old worn lacquer off with paint stripper. The lacquer the Victorians used was quite simple stuff made by dissolving orange shellac flakes in alcohol, usually methylated spirit (denatured alcohol). Some restorers don’t bother, and use a modern synthetic clear lacquer, but the colour looks all wrong beside a pristine example of the original.
You can buy ‘golden lacquer’ at some restorers of antique furniture, as old-time French polish was much the same thing. You might find golden lacquer labelled as button polish because it is made from flakes of button lac and not shellac (different insect), but it isn’t difficult to make your own. Just add shellac or button lac flakes to the alcohol, stir well and leave to dissolve for about 12 hours. Button lac gives a slightly darker, more brownish, look than shellac because it isn’t so translucent. If the golden colour looks too light when you try it on a piece of scrap brass, or if the lacquer isn’t thick enough, add more flakes.
Always lacquer in a warm room Degrease and wash the brass but don’t touch it with your bare fingers after washing as even the slightest fingermark will show under the lacquer. Warm the brass slightly beforehand to drive off any moisture, which sends the lacquer milky, but don’t get it so hot that the lacquer dries almost immediately or you’ll find it difficult to get an even coating, and the colour will be streaky. A hair drier is handy for this. Put the lacquer on evenly with a large, soft artist’s paint brush, or spray it. For spraying you need a thinner lacquer and two or three coats. Hang the parts up to dry in the warm, and wash the brush or spray gun in methylated spirit (denatured alcohol).
The above information, except the bit about spraying, came from a Victorian magazine feature on How Cameras are Made.

ON OLD exposure meters, and old film and plate packets, you’re likely to find a speed rating that doesn’t agree with present-day ISO numbers. Everyone wanted to use their own classification system. Indeed, some plate and film makers didn’t quote a speed from any system. The labelled their products with something like ‘Standard, ‘Rapid’ and ‘Ultra Rapid’. What these meant was anyone’s guess. One maker’s Rapid might even be half the speed of another maker’s Rapid. Maybe that’s why they didn’t quote a speed system number.
     In the UK we used to use the H&D (Hurter and Driffield) system, then we went to the European Scheiner system, then to the BS (British Standards) system and then to ASA (American Standards Association) system which was later adopted by the International Standards Organisation as the ISO system. In America there was a different Scheiner system. In Germany, the Scheiner system was superseded by the DIN (Deutsche Industrie Norm) system and the Russians had their own Gost system though now they use ISO. If that were not enough, makers of exposure meters and tables often came up with their own speed rating systems, and Ilford had a series of Speed Groups. The Scheiner systems were quoted in degrees, with the small degree (°) sign, and DIN numbers used to be written as DIN°/10. It’s not possible to get an accurate comparison between all the systems because different laboratory techniques were used for arriving at the ratings, so you may find comparison tables that differ slightly from the one I’ve given here. This applies particularly to the H&D, old AVO and Watkins numbers.
     There are provisions in all these systems for rating slower and faster emulsions from the ones I’ve given in the table, but if you find anything rated slower than 10 ISO you’re going back almost to Victorian emulsion speeds. And you aren’t very likely to find old films and plates faster than 800 ISO. Plates were often faster than roll films, and if you find a plate labelled Extra Rapid Pan in magazines of the 1930s it was probably about 25 to 50 ISO. When Kodak first brought out its Super XX pan, somewhere around the late 1940s, it was reckoned really fast with a European Scheiner rating of 32°, about 100 ASA, and compared with today’s emulsions it had a grain like footballs.
     If you like doing brain teasers with series of figures in them, you’ll probably notice that several of the systems have a consistent relationship. For example, the European Scheiner rating is one number higher than the BS rating. The US Scheiner rating is four numbers lower than the BS rating. The old Weston rating is one step lower than the ISO rating. The DIN rating is 10 numbers lower than the BS rating and 11 numbers lower than the European Scheiner rating.
     The ISO system is the easiest to use because if you double the number you double the sensitivity of the film. A film with a rating of 400 ISO is twice as fast as one with a rating of 200 ISO. For practical purposes this also works, near enough, with the Gost system and the old Weston system. To double the speed of a film in the Scheiner and DIN systems you add 3 to the number.
     As an historical point, the system that most people call the European Scheiner system originated in Germany but it isn’t really a Scheiner system. The original Scheiner system was developed by a German astronomer named Scheiner for measuring the brightness of stars and was later used to measure the sensitivity of photographic plates by using a rotating shutter to expose them to the light of an oil lamp. It worked because the plates of the day were very slow, and were almost completely colour blind. As faster plates were introduced the Scheiner system of measurement couldn’t cope and, what’s more, the readings from the yellow light of an oil lamp became inaccurate as plates became sensitive to a wider range of colours. Two scientists by the names of Eder and Hecht modified the system by using a step wedge instead of a shutter, and using the light from burning magnesium. Somewhat unfairly, I think, the new system wasn’t named after them. It became known as the New Scheiner system and, later, the European Scheiner system. It was superseded in Germany in 1934 by the DIN system, but you still find it quoted on some film packets and exposure meters as late as the mid 1950s.
     Ilford first introduced its Speed Group ratings in the 1930s when the company produced a photoelectric exposure meter. It was a brave attempt to make things easier for the user by taking letters of the alphabet with each successive letter indicating a doubling of the film speed. When the system was first used, it ran from A to E. This covered the slowest and fastest emulsions Ilford produced, though the A and B rated plates were very slow and were used only for photogravure and copying work. The C rating was for Ilford’s HP, or Hypersensitive Pan. It was thought fast for its day and was the origin of HP2, HP3, HP4 and HP5 films. Fine-grain Pan film, the start of the FP series, was given a C rating. As faster emulsions were introduced, Ilford extended its Speed Group ratings up to the letter I.

ASA(ISO)	BS	EUROPEAN SCHEINER	US SCHEINER	GOST	DIN	OLD WESTON	H&D	OLD AVO	WATKINS	ILFORD SPEED GROUP
10	21	22	17	16	11	8	250	320	160
12	22	23	18	20	12	10	300	400	200	C
C	23	24	19	25	13	12	400	500	250
20	24	25	20	32	14	16	500	640	320
25	25	26	21	40	15	20	640	800	400	D
32	26	27	22	50	16	25	800	1000	500
40	27	28	23	64	17	32	1000	1200	640
50	28	29	24	80	18	40	1250	1600	800	E
64	29	30	25	100	19	50	1600	2000	1000
80	30	31	26	125	20	64	2000	2500	1250
100	31	32	27	160	21	80	2500	3200	1600	F
125	32	33	28	200	22	100	3200	4000	2000
160	33	34	29	250	23	125	4000	5000	2500
200	34	35	30	320	24	160	5000	6400	3200	G
250	35	36	31	400	25	200	6400	8000	4000
320	36	37	32	500	26	250	8000	10000	5000
400	37	38	33	640	27	320	10000	12000	6400	H
500	38	39	34	800	28	400	12500	16000	8000
640	39	40	35	1000	29	500	16000	20000	10000
800	40	41	36	1250	30	640	20000	25000	12500	I

     Unfortunately for Ilford, the company hadn’t got the marketing clout of Kodak, and though some film manufacturers included the Ilford Group rating on their cartons, many didn’t, which meant that users of Ilford’s exposure meter were limited in their choice of film. Understandably, the Ilford exposure meter didn’t sell as well as the company hoped. If you find one anywhere it’s worth picking up because they’re quite rare compared with Westons and other meters. Eventually Ilford dropped its Speed Group system and used the ASA system.
     As I said, you’ll probably come across tables where the relationships between the systems differ from the ones I’ve given. This is because it’s impossible to give an exact relationship where different criteria were used to arrive at the figures. Always treat comparisons, particularly mine, as a guide, not a rigid relationship.
     You may be puzzled why, around the 1970s sometime, film from most makers suddenly doubled, or almost doubled, in speed without changing its name. The answer is that makers removed their 50% ‘safety margin’ on film speeds because users were writing to photo magazines saying that their pictures, particularly colour transparencies, were over exposed, and querying whether their meters needed recalibrating. Ilford’s FP3, for example went up from 125ASA to 200ASA and HP3 from 200 to 250 and then to 400. Recommended development times were unchanged. Adverts talked about ‘New! ‘Faster!’ and so on, but I doubt if many more advanced amateurs were deceived.

YOU'VE probably noticed that different lenses on cameras in your collection have different series of f-stop numbers, and you may have wondered why. If you’ve got a mathematical turn of mind it’s interesting to compare them.
     For example, there’s a Continental system that runs 3.2, 4, 6.3, 9, 12.5 and 18, a system also used by some Japanese lens makers. Then there’s the series we’re all familiar with which, in its smaller stops, runs 8, 11, 16, 22, 32 and 45. The idea of all the series is that the aperture gets smaller as the numbers get larger, and that each successive number gives an aperture that passes half the amount of light of the one below it.
      In an attempt to simplify the numbers, the Royal Photographic Society proposed in 1881 that there should be a Universal System, which became known as the US System (please note, it does not stand for United States System). This started at the equivalent of f/4 because, at the time, no-one in the Society thought that anyone would want to use a larger aperture. They gave f/4 the number 1, and the series ran: 1, 2, 4, 8, 16, 32, 64 and 128, each successive number being an aperture that passed half the light of the one below it. The US numbers 8, 16 and 32 aren’t the same as f/8, f/16 and f/32.
     In your early days of photography you were probably told that the f-number was the diameter of the aperture divided into the focal length of the lens. This is a reasonably accurate, guide but isn’t strictly true because the amount of light passed by an aperture depends on its area, not on its diameter. The area is half the diameter squared, multiplied by the maths constant pie, so though area is related to diameter, you can’t make direct comparisons because it follows a square law not a linear law. However, we can disregard the constant pie because it’s the same all the way through, and compare the squares of the f-numbers.
     Take the first series I gave, the Continental one starting with f/3.2. Strictly speaking, the series ought to start with 3.16227, or the square root of 10. I’m not sure quite why, but a friend who has a degree in mathematics assures me it should. However, lens makers decided to round it off to 3.2. If each successive stop is to pass half the light of the one before it, the squares of the f numbers should double to run 10, 20, 40, 80, 160, 320, 640 and 1280. If we take the square roots of these numbers we get 3.162, 4.472, 6.324, 8.944, 12.649, 17.888, 25.298 and 35.777. Rounding off these numbers gives the Continental system 3.2, 4, 6.3, 9, 12.5 and 18. Why makers rounded 12.649 down to 12.5 and not up to 12.7 I don’t know.
     If we do the same thing with the f/numbers equivalent to the US System which starts at f/4, we get a series 2, 2.8, 4, 5.6, 8, 11, 16, 22 and 32, another series with which we’re probably all familiar.
     However, the principle of a stop passing twice the amount of light as the one numerically above it doesn’t necessarily hold good at the largest marked aperture, even on some famous lenses. For example, f/4.5 used to be a popular maximum aperture of a number of lenses in the 1930s, including the famous Tessar, but most makers continued the series with 5.6, 8, 11 and so on. F/4.5 doesn’t pass twice the light that f/5.6 does. If we square the numbers we get 20.25 and 31.36, so the increase in exposure from f/5.6 to f/4.5 is 1.548 to 1, not 2 to 1. Similarly, a number of lenses had a maximum aperture of f/6.3, but then carried on with 8, 11, 16 and so on. In this case, the increase in exposure between f/8 and f/6.3 is 1.61 to 1. I think it’s quite likely that these makers didn’t want to open the lens beyond its capability, but equally didn’t want to confuse photographers by using a completely unfamiliar series of numbers all the way through.
     All very neat and tidy, but just to put the cat firmly among the pigeons, I have an old Goerz Double Anastigmat lens that has another series running 4.8, 5.5, 6.3, 11, 16, 22 and 32. If we square these numbers we get 23.04, 30.25, 39.69, 121, 256, 484 and 1024. There’s no way, even with rounding off, that these squares double as you go up the series. I don’t know how or why Goerz decided on them – unless it was some complicated formula that took into account dispersion, diffraction, the number of air-to-glass surfaces and possibly other criteria as well. Phases of the moon or the juxtaposition of planets perhaps?

JUST like supermarkets today have their own brands of coffee, washing powder and so on, the larger camera retailers in the classic era had Own Brand cameras. In the UK, Westminster Photographic Exchange had Westex, City Sale and Exchange had Salex, Sheffield Camera Co had Norfolk from their address in Norfolk Row, and Vauxhall Camera Company, not unnaturally, had Vauxhall. These brand names are easy enough to understand, but some are not so obvious. After World War 2, the Dixons chain used the name Prinz, no connection that I can see with the company but a nice enough sounding name. But why Wallace Heaton should choose the name Zodel for its own brand cameras in the 1930s I cannot imagine.
     In the US, the name of the importer was often put on the camera, again understandable, and there’s usually no attempt to disguise who made the camera. On a larger scale, Jack Hannex in Australia started importing European cameras and later Japanese cameras, and spread to accessories using the name Hanimex from the name of his company HANnes IMport EXport. Eventually, the company grew large enough to design and commission the making of its own cameras. In Germany the big mail order dealer Porst used its own name as an own brand.
     Cosina was probably the largest supplier of cameras for own branding, some of which are surprisingly well known brands. Bob Iozia is compiling a huge list of these, and if he puts it up on a website I'll post the address. In the meantime you can see it by going to http://cameracollector.proboards30.com/index.cgi and looking in the section on 35mm Modern SLRs. Have browse round the site while you're there. The members are a friendly lot and the subjects cover all aspects of collecting and using classic cameras.
     With post-war own brand cameras it usually isn’t too difficult to fathom out their origin. Dixons, for example, quite often left the name Chinon on its cameras as well as putting the name Prinz. But some from the 1920s and 1930s often take a lot of detective work searching through McKeown’s or perusing old adverts to find something that looks similar, though it’s easy to jump to wrong conclusions.
     In the case of UK own brands in the 1920s and 1930s, many of them came from Germany. Some were the result of the 1926 Zeiss-Ikon amalgamation which brought together Goerz, ICA, Contessa Nettel and Ernemann. With over 120 models in the group, many quite similar, it was obvious that some had to be dropped. It’s reasonable to assume that many own brand cameras were the run-down of production from one of these four makers especially as some had a distinct ICA-ish or Contessa Nettel-ish look about them. Sorting out the actual model, however, isn’t so easy.
     Zeiss-Ikon wasn’t the only source however. I’ve managed to track down a few, at least to my own satisfaction. Take the Vauxhall De Luxe camera from about 1937 or 1938. If you compare the two pictures I think you’ll agree it has to be the same camera as the Rifax made by the German maker Beier, or Woldemar Beier, Freital, to give its full company name. There’s also little doubt that the Fotet, sold by the Fotet Camera Company in Hatton Garden, London in the 1930s was a rebadged model from the Korelle range made by Franz Kochmann in Dresden. In the late 1920s, City Sale and Exchange offered a neat little 127-size plate camera under its Salex name which was identical to one made by the Italian maker Murer and Duroni in Milan.
     Tracking down the origin of these cameras is a fascinating sideline to collecting and if you're able to track down one that you own it adds a lot to the interest.

IN AN idle moment a couple of years ago I got to wondering how various names for cameras and camera making companies came about. Leica, for example, is well-known, it’s a shortening of LEItz CAmera.
I puzzled over Rolleiflex for a time till remembered the history of Franke and Heidecke who made it. About 1921, the company produced what I believe was its first camera, a stereo camera called the Heidoscope named after Reinhold Heidecke who designed it. When some five or so years later the Heidoscope was developed to take roll film, what more natural than to call it the Rolleidoscope. Later, around 1929, the company produced the architypal and much copied roll film twin lens reflex, so the obvious name for it was the Rolleiflex. So that was that one solved, but I still don’t know why its cheaper sister was called the Rolleicord. Where did the cord bit come from? Incidentally, our German friends pronounce Rolleiflex the proper German way, Roll-eye-flex, not as most English people do Roll-ee-flex.
When it comes to Agfa, the company first started as a maker of aniline dyes with the name Aktien Gesellschaft Für Anilin Fabrikation (joint-stock company for making aniline) so Agfa is an abbreviation of the full company name. The word Clack, as in Agfa Clack, is a word used by numerous German makers for cameras fitted with a simple single-speed everset shutter and is phonetic for the noise the shutter makes. Optima is easy to understand (Optima = Optimum, the best) and Karat is taken from the word used to describe the quality of gold, but where does Silette come from? The suffix ette normally means small, but what is a small Sil? Any of our German friends got any ideas?
Agfa’s partner in the US, Ansco, gets its name from the merger of E & HT ANthony with SCOvill and Adams back in 1902. Most Ansco camera names are straightforward except, perhaps, the Goodwin series. These were named in honour of the Reverend Hannibal Goodwin who is generally recognised to be the first person to put forward the idea of a flexible transparent base for emulsion to produce films. His company, the Goodwin Film and Camera Company, was acquired by Scovill after his death in 1900.
Kodak is a completely artificial word without any derivation and is reputed to have been chosen by George Eastman as a name that was short, easily remembered and could be spelled and pronounced the same in almost any language, though whether he coined it or not I don’t know.
Ilford comes from the town of Ilford in Essex where the company was situated, and Ensign comes from the Union Flag (the British flag often called the Union Jack, not the American flag) which was used by Butcher as its trademark.
How about Graflex? The flex part obviously comes from reflex, but the company was Folmer and Schwing, so where did the Gra bit come from? Possibly from graph, the Greek word for drawing or writing, so Graflex = Graph-reflex?
The name Minolta is quite interesting. The company was founded in 1928 by Kazuo Tashima who made cameras with Japanese bodies and German lenses. He used the trademark Nifca from NIppon Foto CAmera. In 1931 the company was reorganised under the name Molta which comes from the German words Mechanismus Optik und Linsen von TAshima, or mechanism, optics and lenses by Tashima, to indicate that the company was by then making its own lenses. But why use German abbreviations for the name of a Japanese company? Strange. In 1962, the company changed its name to Minolta, but I haven’t been able to find out where the ‘in’ part came from. Nor do I know why the company chose the name Rokkor for its lenses unless it’s something to do with the fact that the word is a palindrome (the same spelled forwards or backwards) and some, but not all, Rokkors are symmetrical designs.
Zeiss-Ikon was formed in 1926 by the amalgamation of Contessa-Nettel, Ernemann, Goerz and Ica under the umbrella of the optical company Carl Zeiss as the controlling company. Ikon comes from the Greek word for picture, so strictly speaking all ‘Zeiss’ cameras made after 1926 should be called Zeiss-Ikon. Zeiss cameras, without the Ikon part, were made by Carl Zeiss Palmos AG for a few years after Zeiss took over the camera maker Palmos in 1902, but in 1909 Carl Zeiss Palmos became part of Ica which got its name from the initials of International Camera Company when camera makers Hüttig, Krügener and Wünsche merged with Carl Zeiss Palmos, the international part coming from the inclusion of the Swiss maker Zuluaf.
All just trivial? No, I don’t think so, but then as a writer I’ve always been interested in the derivation of words, and as a camera collector I’m interested in the derivation of camera names.

WHEN Zeiss-Ikon was formed in 1926 by the amalgamation of Contessa-Nettel, Ernemann, Goerz and ICA all under the umbrella of Carl Zeiss, the new company was faced with rationalising somewhere about 120 models. With variations, this meant over 900 different cameras.
     Some models were dropped, and for those that stayed in production, some sort of numbering system was essential. Zeiss Ikon adopted the code numbers that are familiar to most collectors, though not everyone knows what the numbers mean.
     The numbers are in two parts, separated by a slash. The first part, with either two or three figures, is the model number. Usually this number went up by one when a significant change was made to the model. For example, the original Contax has the model number 540. The model number for the Contax II is 543, and for the Contax III it’s 544.
     I can’t find any reference to models 541 and 542, though Zeiss Ikon enthusiasts have identified six variations of the original Contax that wasn’t officially called the Contax I by Zeiss till the Contax II was introduced. McKeown lists these variations as Ia, Ib, Ic, Id, Ie and If, Maybe 541 and 542 were used in the factory for two of these variations, but I haven’t been able to find them in a catalogue. When I asked Zeiss in East Germany about them, back in the 1960s, they said that was possibly the explanation, but they couldn’t be certain as many records were destroyed or dispersed during and just after the war. Zeiss-Ikon in West Germany didn’t know for sure either.
     Other well-known family models are the Ikonta, starting with 520, and the Super Ikonta starting with 530.
     The two figures after the slash give the picture size. For example, the original Contax was 540/24, this giving the picture size as 24mm by 36mm. An Ikonta 520/16 takes pictures 6cm by 6cm, and a Super Ikonta 530/2 takes pictures 6cm by 9cm.
     The picture sizes don’t seem to follow a logical sequence, and I’ve been unable to find sizes for numbers 19, 22, 23, 25 and 26. Once again, Zeiss said they weren’t sure, but probably these were numbers allocated either to picture sizes of ‘amalgamation models’ which Zeiss-Ikon discontinued, or possibly made only a modified prototype (now there’s an intriguing thought). Or, possibly, they were numbers for proposed new film formats that never came about (another intriguing thought).
     For some cameras only the model number was given in the catalogue, with no slash and no picture size. Zeiss said these probably took pictures either 4.5cm by 6cm, or 22mm by 31mm. For example, the Ikonta 521 with no picture code took pictures 4.5cm by 6cm, and the little folding Bobette I 548 and Bobette II 549 both took pictures 22mm by 31mm.
     Zeiss were kind enough to send me a list of all the code numbers for picture sizes they had on record, and I’ve set these out in the table below.

Code number	Picture size		Code number	Picture size
1	45x107 mm		12	4x6.5 cm
2	6x9 cm		13	13x18 cm
3	6.5x9 cm		14	5x7.5 cm
4	6x13 cm		15	6.5x11 cm
5	8.5x11.5 cm		16	6x6 cm
6	8x14 cm		17	8x10.5 cm
7	9x12 cm		18	3x4 cm
8	9x14 cm		20	18x24 mm
9	10x15 cm		21	24x30 mm
10	9x18 cm		24	24x36 mm
11	13x18 cm		27	24x24 mm