Well, to start a lot of chemistry was involved.

And this was Louis Lumière’s territory.

A professional chemist, it was Louis who over the course of nearly 20 years was the one who would write, experiment, and later perfect the complex technique that would result in producing the world’s first colour photographs, autochromes.

In the above photo you see an autochrome self-portrait of Édouard Blanc, one of the chemists who worked with the brothers at the Lumière factory in Monplaisir (Lyon).

The photo was taken around 1907.

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However, while making autochromes was a complex and costly process, the idea in fact was very simple.

So simple, indeed, the digital photographs we take today on our iPhones or Canons still rely on the same principle.

(Except for the spuds...)

1. Get some potatoes...

2. Mash them really, really finely until you’re left with tiny particles of potato starch grain...

3. Add three coloured powders:

an orangey-red, a green and a violet blue

4. Mix together and apply onto some varnished glass plates..

5. Add some “lampback” (soot from oil lamps) to fill in the gaps between the grains, and then use a very big machine to apply an incredible five tons of pressure per square centimetre...

6. 6.Finally, and this was the tricky part... adding the light-sensitive layer. This was made up of a Black and White emulsion of gelatino silver bromide, a process which was discovered by R.L. Maddox in 1871 and used in B&W photography ever since.

If you’re interested to read more, the George Eastman House has a longer description of how autochromes plates were made and taken by photographers.

At Mondrian’s Room, we are fortunate to have two such boxes, one in immaculate condition.

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To see a video of exactly how autochromes were made, based on the above process, the French scientific research centre CNRS has produced an excellent video illustrating all the above various stages of autochrome production, which is definitely worthwhile watching.

To view the video, open the above link

and click the play button.

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7. Under a microscope this is what we can see.

8. The final ready-to-expose autochrome plates were then packaged by the Lumières in these beautiful boxes.

The CNRS in France have produced a brilliant website on autochromes which contains all the information in English and French, particularly on the idea of additive synthesis (combining colours).

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