Paterson Orbital Colour Colour Print Processor - complete.

In excellent like new condition boxed and complete with instructions 

Processing sheet film is a perennial problem, especially for the beginner. The Paterson Orbital tank, designed for processing colour prints, is extremely useful for formats up to 8x10 inches. It can take one 8x10 inch or 18x24cm or whole plate; or two 5 x 7 inch/13 x 18 cm/half plate; or four 4x5 inch/9x12cm (or presumably quarter-plate, though we have not tried it).

As the illustrations show, it is essentially a processing tray with a curved bottom and a light-trapped lid. It can be loaded in the darkroom or in a changing bag, after which processing can be carried out in normal room lighting. It is normally used with the domed support base, this is the manual version ,but it can be used, simply as a covered, light-tight tray.

Better still, the volumes of chemicals needed are absurdly small, as noted below.

Filling is via the hole on the top; drainage is via the corner marked with the arrow (top left). 

The smaller formats are separated with 'golf tees' that are stored in the lid (above and left). Here it holds one sheet of 5x7 and one of 4x5 inch.

Although film can be processed in an unmodified Paterson Orbital, it is a good idea to roughen the base so that the film does not stick to it. This has at least four advantages. First, the film is easier to get out. Second, the backing is infallibly removed during processing: without the roughened base, the backing may have to be removed in a separate tray while re-fixing. Third, it allows the film to slip about during processing, greatly reducing the risk of uneven development if the motor base is used. Fourth, there is no danger of chemicals being trapped under partially-stuck-down films, so processing is more consistent and washing is more certain.

We roughened ours (we had two) by 'kissing' them repeatedly with a Dremel tool fitted with a small burr. This requires careful washing afterwards to get rid of the debris. We have heard of those who have placed innumerable tiny drops of adhesive on the base, and yet others who have carved deeper channels. All seem to work but the choice is yours

The slight curve of the bottom of the tray is more visible here. The tray will sit flat on the table on the ring that goes over the base.

The snap-on top is equipped with a light-trapped filler aperture and the light trap can be removed (it bayonets out) for cleaning

The power base  adds even more ease It moves the tray in a sort of lurching swirl and is obviously less hard work than agitating by hand. It is also easier to pour the chemistry into the tank while agitating, which helpful.

processing sequence

The processing sequence is exactly the same as for any other daylight tank. Fill with developer (via the top); drain (via the corner); add short stop or fixer; drain; wash, either by multiple changes of water (half a dozen changes, each with 30 seconds agitation, should suffice) or with running water.

Developing times of at least 5 minutes are all but essential, in order to avoid uneven development, and for the same reason, developer should be added while the tank is being agitated. With longer development times (8-10 minutes) this becomes ever less important.

chemical volumes

Regardless of the quantity of film being developed, the Orbital requires a minimum of 55 ml (two ounces) of processing chemicals, though most people use a little more: anything from 75 to 150 ml (3 to 6 ounces). With such tiny volumes, 'one shot' processing is entirely feasible.

Do not be deceived by those who suggest that this is not enough developer. Most of the developer, in any tank, is used for wetting the film quickly and evenly: the amount of developer that does the work is a teaspoonful or two.

temperature control

The Orbital Processor was originally designed for processing colour prints, so black and white should not be a great problem. The tray has quite a high thermal capacity -- it's a good-sized chunk of plastic -- and the developer can of course be brought to the appropriate temperature in a water bath. Even so, we find it easiest to process at ambient temperature, making appropriate adjustments for deviations from the standards of 20 C/68 F or 24 C/75 F.

agitation

Agitation must be constant, given the very small amount of developer used. As this one is the manual version you will need significantly more than the minimum 55 ml (2 ounces) of chemicals. We recommend about twice as much. At three times as much, there is a significant risk of spillage out of the drainage corner.

large format without a darkroom

Because the Orbital can easily be loaded in a changing bag, there is no need for a darkroom. Then, there are several kinds of alternative processes which can be conducted under subdued room lighting, making contact prints either by sunlight or via a UV 'sun lamp'. This allows even those without access to a darkroom to indulge in 'real' photography.

It is worth remembering, too, that if you work this way, you will be working with a good deal more precision than most Victorian photographers -- and if we were as skilled as the best Victorians, we would be very happy indeed.

In excellent like new condition and complete with instructions bought some time ago but never actually used no box but will be well protected for transport

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