I saw this device on Ebay with a very vague description – no real indication as to what the device might actually be. It was made by Leitz (the makers of the Leica camera) which suggests it would be both well designed and well made. So I put a bid in and got the device for £8.00 – a bargain! Fortunately for me, the device came with full instructions, making the use of the device clear (full instructions are three small pages of text plus a diagram).
The device itself has the maker’s name – Leitz Wetzlar, Germany – on it but no other writing. The box has the additional information of “Eldia 17900W” but no more and that is all the information that I had when I bought it.
The instructions (four small pages) have the additional information “Eldia printer” and “printing device for transparency film strips”. It seems that the device is intended for producing projectable positives on black and white film from black and white negatives. Searching on the Interweb suggests that this device was first introduced in about 1930 (dates on the Interweb vary a bit). Leitz Wetzlar was incorporated into a GmbH in 1930 and this name is printed on the instructions – “Leitz Wetzlar GmbH” so my device was made in or after 1930.
Early versions, according to the Interweb, had nickel plated knobs, later versions had chrome plated knobs and the last versions had plastic knobs. Mine has anodised aluminium knobs – so much for the Interweb! Both the device itself and the instructions say that it was made in Germany rather than West Germany which might suggest that it was made before 1945 but might also mean that it was of late enough manufacture that the distinction between West and East Germany was old hat and West Germany had returned to calling itself just Germany. On balance, I think mine is a later rather than earlier model.
The device itself is very simple – no lens, no shutter, no meter. It is fully manual and really simple. The device is basically a box with semicircular ends. It is made from brass which is painted black with a coarse crinkle finish. The is a hinged front – also brass painted black but with a finer crinkle finish.
The top has the only controls there are – a knurled knob at either end. These are different heights – the right hand one is taller and has an arrow embossed on top to indicate the direction of turn. The left hand knob is lower and has no arrow. Half way between these two knobs is a spring catch that holds the hinged front in place.
The rear of the device has a red glass window measuring 38 by 30 mm. It is far from clear why this window is there. In film photography it usually indicates illumination for blue sensitive emulsions but this red window is not involved in illuminating anything. if the red window was replaced by solid metal, the device would work just as well.
The front of the device has a hinged flap. This has a central clear window. On my device, this window measures 25 by 19 mm which is half a standard 35mm film frame. It can be replaced with a larger window measuring 25 by 37 mm. This hinged flap also contains the maker’s logo – “Leitz WETZLAR” and the country of origin: “GERMANY”. This flap is held in the closed position by the spring mentioned earlier.
When the flap is opened, the front of the device is exposed. There is a large aperture – 82 by 35 mm – with a glass window centrally. This time the glass is colourless but, as with the red window on the back, this glass window serves no discernible purpose. On the right side of the glass window is a sprocket shaft. When rotated, this shaft clicks once every time four sprockets pass the front – this equates to half a standard 35mm film frame. This allows you to measure one frame (two clicks) or one half-frame (one click) when winding the film in the dark. The inside of the flap has two guides to hold a strip of developed negatives.
If you open the flap, it is then possible to remove the top of the device – this top is just a push-fit lid with two holes. The two knobs that protrude through the holes are attached to spools to hold a length of 35mm film. The instructions say the spools will hold three metres of film which is about two 36 exposure cassettes worth.
In use, you load a length of unexposed copy film onto the spool with a small knob and pull the film across the glass window with the emulsion on the outside and on to the spool with a large knob. The strip of negatives that you want to copy fits between the guides on the flap, again with the emulsion on the outside. Note that the unexposed film you use must be copying film that can be used under a red safe-light. When the flap is closed, the emulsion side of the two films will be in close contact.
You expose the copy film through the glass window in the flap – through the negative you want to copy – by holding the front of the device 1.5 m from a 25 watt incandescent bulb. If you use black and white film and black and white negatives, you will end up with a black and white positive for projecting which is the original purpose of the device. If you use colour reversal film and colour slides, you will end up with a duplicate colour slide.