Tri-colour Photography Intro

 

Whitby_Harbour2_Assembly

A normal shot on a sunny day of the harbour at Whitby. Very intense colour. But then perhaps look more closely at it, grass was never like this – and what are the ghostly coloured figures parading on the pier – and what’s happening to the sea? You are in the unmistakable presence of a colour photograph made with black & white film, using tri-colour photography.

Whitby_Harbour_Blowup

… which cutting to the chase is using 3 separate exposures, through red, green & blue filters, onto black & white film and later recombining them to make the final full colour image.

The idea is not exactly new, it goes back to the dawn of photography, and until the first full-colour Autochrome plate of 1907 arrived, was the only practical way to make colour photographs. The pioneering worker E J Wall as early as 1925 was able to write a ‘History of Three-Colour Photography’ summarising the enormous field the work had encompassed. An early preoccupation was how to avoid the delay between each exposure while the filter was changed & the film or plate wound on or exchanged. This resulted in such patent novelties as these;

3CC_Composite_Cameras_web

… but very few made it much further than the drawing board.

But colour photography was seized on commercially in the late 1920’s, in the aftermath of the Great Depression, and although unprepared was dragged kicking & screaming into advertising. Much static colour work could be done with a single camera and separation filters, but for work with models a means of shooting instantaneously was needed. Leaving the many patent failures aside, for practical commercial purposes it all boiled down to a relatively simple camera with one lens and a means of splitting the beam internally into the red, green & blue records. There were a number of models, but they were all basically the same layout as this 1938 Devin camera. Because the colour photograph could be taken in real time they were came to be known as ‘one shot cameras’.

One_Shot

Commercial 3-colour cameras were necessary even though processes like Autochrome were around, as although their results were pleasing when viewed directly, they simply weren’t capable of producing satisfactory separations for colour ink printing. The use of one-shot cameras for producing advertising colour carried on right up into the 1950’s, resulting in a style of gorgeous but still rather static colour.
The time of the commercial one-shot cameras could be compared to that of the dinosaurs, it lasted only until good quality colour film was available, and then disappeared almost overnight. They had serious technical limitations, insofar as they were built to work with one fixed medium focus lens, needed more fine tuning to keep them in perfect order than a concert grand, and even then were renowned for the fuzziness of the images.
The photographer who pushed 3-colour almost to it’s limit was Madame Yvonde, who before WW2 worked with the British Vivex camera & laboratory, creating artistic & commercial colour images with live subjects, sometimes even on location. Here she is doing her best to convince that it was possible to hand-hold the massive Vivex camera, which it certainly was not.

MY_Vivexcamera   MY2   MY3


Leaving the historical commercial one-shot work aside, we’ll now concentrate on making tricolour images today using standard camera gear.


Limitations

1] One inherent limitation is very obvious, that of the difficulties of registration. The image of Vivian Leigh is taken from a modern print made from the original separations – the films had shifted dimensionally so much over time that accurate registration wasn’t possible. However Adan Lowe made this work in the picture’s favour by letting the misregistration run as coloured lines down the edges of the green coat.

2] Subject movement – the real world doesn’t stay still for long. A day without some sort of wind is almost unknown, grass & trees move, waves by their nature don’t stop for the camera. People might co-operate but it’s all a gamble.


So why opt to work now with this most intransigent of processes? The photographer William Curwen who worked extensively with the process summed it up this way;

‘Digital gives us an almost perfect mathematical description exactly one pixel “deep” of the surface appearance of what we look at, whereas film records something of what we see and how we feel about it. One looks like a photograph, the other like a painting….Tricolour capture with film records more than we see, and all we look at’


Advantages

It might be surprising that there are any positive aspects to shooting 3C at all. Tricolour is technically enormously challenging  when working with conventional equipment, primarily because it’s a 3-shot process. But that in itself is part of the ‘syntax’, the time dimension enters into the work. Choosing the subject, and then making exposures that work with, rather than fighting the technique, is the goal.
But a lot comes down to the fact that the records are conventional black & white pictures made on normal panchromatic film, and all the techniques of black & white work are there to bring into creating the colour image.

1] Freedom from the colour film syntax. It’s quite easy to forget that colour film was always a bit of a lashup, and although a highly sophisticated product now, it’s expensive, tied to a dedicated process (C41 or E6) and manipulation prior to getting the image into the computer environment is limited.

2] On the other hand, 3C allows the use of literally any black & white film that’s panchromatically sensitised sufficiently to separate the colour spectrum into 3 areas. Great range of speed choices, from almost zero to many 1000’s of ISO.

3] That B&W film can then be controlled with different types of developer to get specific qualities, e.g. using Rodinal for high sharpness, fine grain developers, even special developers such as pyro. Plus the big advantages of low working temperature, high exposure latitude & low toxicity.

4] Time, the extra dimension. The time delays between the consecutive exposures can result in small shifts in the way the colour reconstructs, possibly due to wind movements in foliage, water etc. This may then produce small & subtle colour patterns, which rather than giving the game away can hint at the extra dimension being explored. On the other hand if they’re large areas of variation, you’re possibly straight back in ‘Disadvantages’ category 2, above.

5] The tri-colour filter set, red green & blue, used for exposure can be very steeply cut, resulting in exceptional purity & saturation in the end result. By comparison conventional colour films are a brave attempt at a lashup.

Some films offer surprises.  The quick test (below) just before the light failed one afternoon was on the relatively new film, Foma Retropan 320. This has an unusual emulsion with an aura that’s a throwback to earlier films, limited anti-halation properties and a tendency to offer up blocked highlights. The filters were the ‘Quality Street’ set of red, green & blue gels which are another way of making life just that little bit more difficult. Hardly technical filters, but sufficient to separate the spectrum into 3 individual negatives which can then be layered together to rebuild the scene.

Sweets_5_Assembly4

So with these crude filters coupled with a rather strange film with as yet uncharted performance, not a lot of colour present. But what does come through is subtle, & to my eyes reminiscent perhaps of 1907 Autochrome.

[incomplete, to be continued]