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Exakta A Manufacturer: Ihagee Date 1932-(c)1940
The original 1933 Exakta wasn’t called Exakta A until the introduction of the model B, later that year. This first Exakta had a focal plane cloth shutter with speeds of B(beliebig), Z(Zeit)(T), 1/25, 1/50, 1/100, 1/200, 1/300, 1/600 and, rather amazing for its time: 1/1000s. For comparison: comtemporary Leicas had a top speed of 1/500s. Only two years later did Leica Introduce a 1/1000s shutter on the model IIIa (G).
Exakta B Edit
The Exakta B evolved in parallel with the model A, but had a second shutter speed knob on the right of the body. This gave additional speeds from 12s to 1/10s and a self-timer with 1/10s, 1/2s, 1, 2, 3, 4, 6 and 12 second speeds. In total, this gave the Exakta B a shutter speed range from 12s to 1/1000s. This shutter setup and range was to be continued in later 35mm and 6×6 models of the Exakta.
From 1934 the thread, like on the Exakta A, was enlarged (see lenses). This third version of the model B saw the introduction of a transport lever (on the left of the camera!).
Night Exakta Edit
Made from 1934 to 1937, Night Exaktas were made with a larger thread to allow larger aperture lenses. This also means lenses can not be interchanged with other VP exaktas. Large apertures were especially important because films of the time were rather slow. Meyer Primoplan 80/1,9, Zeiss Biotar 8cm/2 and Dallmeyer 80/1,9 were available. Night Exaktas were made in two designs, based on the Exakta A (only high shutter speeds) and on Exakta B (slower speeds also available). Given the slow film material and the need for large lens apertures, one wonders how useful a Night Exakta with a slowest speed of 1/25s may have been in a night shot situation.
Exakta C Edit
The design for the Exakta C was based on the model A or B. The difference is, the Exakta C has interchangable backs, one for 127 film and one for plates. When used with film, the Exakta C is very similar to the models A and B, meaning there are versions with and without the slow speeds (see above). When the plate adapter is mounted, however, the Exakta C practically ceases to be an SLR!. The image is focused on a second ground glass, not in the reflex finder but in the plate back. Remove the ground glass from this special back and a film plate with dark slide can be inserted, much as on any view camera. This ground glass and film plate are at a slightly larger distance from the lens than the VP film would be in the film back. This has some major consequences. First, for use with film, an adapter ring has to be used between the body and the lens. This compensates the smaller lens-to-film-plane distance. The reflex finder can only be focused reliably with this adapter ring in place.
Using the plate back, it becomes highly impractical, if not impossible to use the reflex finder. There is a way, though. Focus the image in the reflex finder with the adapter ring in place. Remove the adapter ring, remount the lens on the body itself and your shot should still be in focus. A rather clumsy way of taking a picture. The ground glass focusing in the plate back seems to bee a better option, albeit upside down and mirrored. In practical terms, both ways rule out shooting moving subjects or changing sceneries.
Usually, the diagonal of the film format is about the same length as the “normal” or standard objective. In this case, 40x65mm gives a diagonal of 76mm, thus the standard lens for these Exaktas is a 75mm lens. Ihagee produced an Exaktar 75/3,5 and had other standard lenses made by reputed German makers such as Zeiss, Meyer and Schneider. A wide array of lenses was produced by a lot of different makers. Objectives from a Zeiss 55 mm Tessar to 360mm Schneider tele-Xenar were available. Not long after the introduction of the first Vest Pocket Exakta, in late 1933, Ihagee changed the screw mount a little. This prevents the interchangability of late lenses on early bodies. The earlier 39.5 mm wide screw mount with a 0.5mm pitch was replaced by a 39,8/0,75mm thread. A puzzling decision, as no functional benefit is immediately obvious. Interchangable lenses were probably only made for the somewhat larger screw mount, thus for cameras from late 1933 onwards.