Agfa Isoly
With Isoly , Agfa designated a series of photo cameras for the 4x4 format and type 120 roll film presented in 1960. The Junior, I, II and III models differed only in their differently complex lenses and closures .
Situation around 1960
Single cameras
In the 1950s, simple cameras still used the 6x9 format, primarily to make prints easily accessible with contact copies. Since the trend in the price segment between 150 Deutsche Mark (DM) and 300 DM very soon went towards 35mm film, entry-level models also required smaller dimensions in order to be considered modern. The way there led on the one hand to more compact housings and on the other hand to smaller formats, from 6x6 to 24 mm x 24 mm ( Agfa Rapid ) or 28 mm x 28 mm (Kodak Instamatic ). The Isoly was in the middle of this development - the argument of the contact prints played very soon almost no role.
Technical possibilities
Modern plastics in particular made it possible to break new ground with simple cameras: until around 1960, more complex cameras had a die-cast aluminum housing, which, however, had to be laboriously reworked in the factory and was therefore out of the question for simple models for reasons of cost. At first only a sheet metal construction could be used, but the first plastic housing appeared as early as the late 1930s with the Trolix box . However, these were still very fragile, and it wasn't until the thermoplastics of the 1950s that a usable material became available. So you could keep the Clack quite compact. Further advances then allowed more complex shapes and thus made it possible to replace the aluminum housing.
Another aspect was the choice of film: 35mm films required a counter that could be saved with a roll film. For this reason, the conventional roll film of type 120 was used for the Isoly , which, however, was exposed in 4x4 format, which resulted in 16 exposures per film. The type 127 roll film had already disappeared more and more from the market in the 1960s, which is why the more common type 120 roll film was used for the Isoly.Of course, the optics for smaller formats also had to be positioned more precisely, but large-scale production was already so precise by now, that you got by without expensive adjustment work. A sales argument for cameras with 4x4 format at the time was the possibility of getting slides in the so-called "Superslide" format, which are approximately 1.7 times the size of conventional 35mm slides and thus offer approx. 95% more negative size.
camera
Basic construction
The Isoly used a plastic housing with a pull- down back. There was a large lever on the bottom of the camera that could be turned to unlock. This housing was later adopted only slightly modified by the Optima Ia and the Silette models derived from it . The roll film made it possible to do without a mechanical frame counter, for this there was simply a window in the back wall, which showed the frame number printed on the paper of the film. The transport wheel on top of the camera had to be turned until the next number appeared in the window. One film enabled 16 recordings.
In contrast to Clack and Click, the Isoly looked much more modern, with its flat housing that ended with a metal cap. A special feature of the Isoly I and Isoly Junior was the slightly curved film plane corresponding to the Click and Clack models, in order to accommodate the one and two-lens lenses. The Isoly II, III and Isoly-Mat had a film pressure plate.
All Isoly cameras had a hot shoe with electrical contact.
Isoly I
The Isoly I for 37 DM was the entry-level model until the appearance of the Junior , it only had an achromatic f / 8 lens with a 55 mm focal length. The shutter offered two times plus B for long exposures at 1 ⁄ 30 s and 1 ⁄ 100 s.
Isoly II
The Isoly II already cost 46 DM, but it offered the three-lens Agnar f / 6.3 55 mm with good image quality. The successor IIa differed in an Agnar f / 5.6 with unchanged focal length.
Isoly III
The Isoly III offered been an amazing for that time equipment for just 69 DM, namely, the fast lens Agnar f / 3.5 60 mm and the closure Prontor 250 S, which takes its name to 1 / 250 s handed, also could set 1 ⁄ 30 s, 1 ⁄ 60 s, 1 ⁄ 125 s and of course B. The successor IIIa had an Apotar f / 3.9 60 mm with a Pronto lock. Apotar referred to a more elaborate, but also three-lens construction with two cemented lenses that were better corrected than the non-cemented Agnar lenses.
Isoly Junior
The Isoly Junior was added in 1961 as a real entry-level camera, since it only cost 25 DM. In return, it only offered a single-lens f / 11 55 mm lens with correspondingly poor image quality. The trigger located directly on the shutter offered further savings, with a (covered) hole in the housing cover. Of course there was only one exposure time.
Isoly Mat
The Isoly Mat had a limited automatic system, in contrast to the Optima , its control could not influence aperture and time, but only the aperture. The shutter always worked with 1 ⁄ 70 s, so you could not - apart from long exposures - take photos in as little light as with the Optima, especially since the lens was only a Color Agnar f / 5.6. The designers accepted the lower light intensity in order to obtain a greater depth of field, as the distance setting worked with three symbols for uncomplicated handling. With the focal length of 55 mm it worked well. For flash photography, however, there was a meter graduation on the underside of the lens. The advantage of the automatic was the more precise exposure, which was of great benefit for color films, especially slide films.
There were three levers on the lens of the Isoly Mat , one with the positions B (for long exposures), A (for automatic mode) and flash, then the shutter worked with 1 ⁄ 30 s. With the flash, the aperture value could be adjusted from 5.6 to 22, with the automatic the film speed from ISO 10/11 ° to ISO 250/25 °.
The limited exposure control was later taken over by Isomat Rapid .
In contrast to all other Isoly models, the Isoly Mat did not have to be tightened separately by hand, but was self-tightening.
Natarix set
For close-ups, Agfa had the Natarix 44 set ready, consisting of two close-up lenses and a plexiglass wedge as a viewfinder offset for parallax compensation .
