Super-Plex Daylight Loading Developing Tank for 35mm film


The Super-Plex daylight loading developing tank is believed toi have been made in Austria by Friedrich Fisher of Vienna.

It is sized for developing 36exposure 35mm film. It cost £3.18s.6d (£3.93p) in 1952. It seems that the tank shown below dates more recently than 1952, as the box has written on its underside, in pencil, "Superplex 35mm Developing Tank £6-5-0" (£6.25p). Since plenty of UK families emigrated to Australia during the 1950s & 1960s, the tank was presumably purchased in the UK during these years and taken to Australia by a photo' enthusiast. Neil says he was given the tank in 1977 by Mr. Walter Gibson, a member of the (then) well know Gibson’s Confectionery Company, in Perth. It was in almost new condition and Neil is positive no parts were missing.

Other Daylight Loading tanks from (it is believed) the same manufacturer, but designed for developing roll films, can be viewed here (Simplex ~ 120/620 size only), and here (the Superplex ~ 127 to 116 size roll films).

Notice that the tank described on this page is named Super-Plex, while the tank for various sizes of roll films is called the Superplex. Where and how this naming confusion arose, is unknown, but by 1952 Photax, the (by then) UK distributors, were trying to reconcile the situation by referring to the Super-Plex as the SuperFlex.

My thanks go to Neil Dunbar, whose home is in Australia, for sending me the following images, together with his description of the tank and his recent experiences with using the Super-Plex during January 2013.

Neil comments:
Loading the tank.
I only found one difficulty and that was the use of the cutter blade which serves to sever the film close to the cassette. (This action separates the film from the cassette's central spool).
I ran the film loading and cutting process with some waste film several times so I could examine the process in detail. On all occasions the knife edge creased the end of the film considerably.
I sharpened the cutter edge to ensure it was very sharp, but cutting efficiency only improved marginally and still caused creasing of the film.
If I had to use one the Super-Plex frequently I would avoid using the last two frames on the film, as damage to the emulsion on these trials affected about 45mm of the film end.

Developing the film
Film development is fine.
But I discovered the thread for the tank lid does not seal, as some leakage occurred during the agitation process while using the spiral's agitator rod.



This image shows all of the components of the Super-Plex daylight loadinmg tank for 35mm film.


A small hole is punched into the film end using this 'punch jig'. There are two lugs moulded onto the punch jig base which locate into the film sprocket holes

The reason for punching a hole into the end of the film is so that the film can be attached to a hook and line, which are themselves attached to the spiral. The hook and line are used to pull the film into the developing spiral.


This smaller picture serves only to explain the above statement
In practice, the film has to be attached to the spiral's hook via the tank's side entry port, as shown in the views below.

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Having had a hole punched into the end of the film protruding from the cassette (see picture, left), the film is removed from the 'punch jig' and the 'jig' takes no further part in the process.

The 35mm film cassette is then placed into the cassette holder and the film is passed between the roller guides and through a stainless steel film guide.

This view shows the tank with its sliding side access door in the 'open' position, ready for film loading.

The two thumb tabs, either side of the entry port, are rotated upwards through 90 degrees once the sliding door is closed, to seal the tank.


The developing spiral, showing the stainless steel hook and line arrangement, used to draw the film into the tank.


The draw string, between the film and the spiral, is attached to the film in preparation for loading the film onto the spiral.

Please note that in this picture the film is not following the correct path through the roller guides. This is a result of uncertain experimentation when these series of photographs were taken.
The correct film path is believed to be as in the 3rd picture down in this explanatory series of pictures.



At this point, the spiral handle is rotated clockwise and the cassette holder assisted into position on the projecting base before placing and securing the rectangular box shaped, light proof, cover over the cassette.

Please note that in this picture, the silver coloured Ilford cassette (as shown in the picture above) has been replaced by a black plastic reloadable type. The film path in the picture alongside is believed to be correct.

Neil further adds:
The bare steel post is positioned to prevent distortion of the film when pressure is applied to the film edge by the vertically moving cutting blade (see below). When the film is fully wound onto the spiral and still attached to the cassette spool, the cassette holder base is automatically pulled up tight against the tank, positioning this post directly adjacent to the cutting location.

As can be seen in the image below, there is an offset semicircular aperture in the tank housing directly above the point where the file disappears into the tank. The film cutting knife passes through this aperture (see below). The post on the cassette holder base is automatically pulled up to this point at the end of the film winding process, due to the film end still being attached to the cassette spool.

After placing the light proof cover over the projecting base, the film is wound into the tank using the spiral crank handle on the tank top.

The film cutter (a vertical metal strip with a cutting edge on its lower end) is then used to cut the film close to the cassette. To do this you move the small tab protruding on the right hand side from the cassette holder base back and forth, while applying gentle downward pressure on the knife.

The effect here is that the cutting edge of the knife drops between the film guide rollers, severing the film. (You have to feel for the rollers with the knife to find the film cutting point).

The film entry port door is then slid into the 'closed' position and the thumb tabs turned upwards through 90 degrees to seal the tank. The thumb tabs are attached to cams that press against the sliding door and so keep the door hard sealed against the mating face of the tank. There is no rubber seal involved.

Light could pass through the slot where the cutting knife enters, but there is no felt light trap. Instead, the cutting edge, on insertion, separates two fine spring loaded metal plates which press against the blade and provide a light seal. The cutter must be left in place throughout film loading, as the cutting edge is raked at an angle and would keep the blades open (allowing light past the rake angle) until the point of the blade was removed.

Once the film is cut, and the film end pulled into the tank spiral, and the film entry port door closed, the knife can be removed.

The funnel is positioned to aid the entry of the film processing fluids (developer, stop-bath and fixer).

The top surface of the tank lid, with the name moulded into the Bakelite.
The characters below the word SUPER-PLEX read;
PAT. APPL. MADE IN AUSTRIA

   

This page last updated: 18th February, 2013