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Hello,
I am not sure if this is the right place but someone might know and help. I came across really wonderful autochrome image that I would like to buy. I am not sure, though, how autochrome images are displayed. As transparences they were not made for permanent display I guess. Also, does anyone know about permanency of autochromes?
thanks a lot,
Jan
Hello from France
Autochromes can be displayed like regular transparencies. However they are quite dark due to the principles of the process since many black silver grains do remain in the image.
The colours used in autochromes are probably more stable than many colour slides of the sixties (with the exception of kodachrome) stability comes from the fact that colours are not generated by the process itself, like many modern chromogenic image processes, they are already there in the small grains of potatoe starch.
You should send an e-mail to Prof. Gandolfo in Paris, he is one of the best specialist of autochromes, he'll be happy to answer.
Prof. Gandolfo has tried to re-manufacture autochrome plates with his students at the Louis Lumière National School of Photography (ENSLL) , this is a real challenge, exceedingly difficult since many strages of the process e.g. processing, coulouring and coating potatoe starch were made at an industrial level with special machines and secret know-how not described in patents.
Prof. Gandolfo is a regular contributor of the French LF forum, to get in touch with him look here http://www.galerie-photo.info/forum/...php?f=1&id=252
Suggested reading : a nice article by Henri Gaud, French professional LF photographer about a collection of autochromes he acquried at an auction.
http://www.galerie-photo.com/autochrome_plate.html
Thanks for the link, Emmnanuel, most interesting.
G
Emmanuel, thank you very much. I was thinking of permanent display, I would like to frame this image and have it hanging on my wall. May be a little light box behind? I do not know. Anyway, I will contact Professor Gandolfo. Once again - thank you very much,
Jan
Dear autochrome friends.
I have no idea of the actual resistance of colours in an original autochrome exposed to a small light box. Only a specialist like J.P. Gandolfo can tell you. He has taken care of the Albert Kahn Museum collection (72,000 plates recorded between 1910 and 1931) in Boulogne near Paris.
But for sure you can keep them for decades in a dark box without noticeable degradation. At least, I mean : degradation effects similar to a B&W negative. Actually it is a B&W slide obtained after a classical reversal process. Plus a self-aligned colored mosaic of potatoe starch grains, the registration between the B&W slide and the coloured mask being perfect by the mere principle of the process.
In the article by Henri Gaud one can see that some plates exhibit some "rusty" spots, could be due do a defect in the silver halide layer. The coulours in autochromes have a low saturation, which is not unpleasant.
I do not know which coulours are used in autochrome plates. The process was developed around 1900 at a time when many organic dyes were already in use at an industrial level.
J.P. Gandolfo has told me that the process was developed only a few years after the first B&W panchromatic plates were made available.
I would not dream of long-time resistance of autochrome coulours to daylight similar to what you can expect from painters's colours or Roman mosaics based on metallic oxides.
Henri Gaud can give more details on how you can scan or re-photography an autochrome perfectly in order to get a copy.
This suggestion just in case you would eventually prefer to keep the original in a safe dark box and only display a copy ;)
Hi Jan,
There was an exhibition of the work of the English photographer Emma Barton at The Birmingham Museum of Art in 1995 and some of her Autochromes were displayed using backlighting. The colours were different but pleasent.
Best wishes,
Pete.
I just had en e-mail exchange with Prof Gandolfo.
To put it briefly, he does not recommend permanent display of autochromes on a light box.
He has conducted accelerated ageing tests on dyes similar to those used in autochromes and his conclusions are that it is better to keep autochromes in a dark box for maximum lifetime.
At the Albert Kahn museum, the previous curator never allowed the display of original autochromes on a light box. Only good quality copies on transparencies were shown to the public.
Now we can object that a museum should always be excessively cautious with treasuries that we need to preserve for future generations when we do not know how to prevent slow degradation.
A private owner, however, can do what he wishes of course.
My personal choice if I had autochromes would be to experiment with the challenge of making the best possible transparent copy with modern techniques.
Simplest wold be to put an apo-ronar back to work and make a picture of the autochrome at 1:1 ratio or close to on a LF colour slide ! Or try a flatbed scanner, probably a good one (no drum allowed of course ;) )
If some of you are interested in what could be the best process to make a transperent copy of an autochrome, I'll ask J.P. Gandolfo and Henri Gaud. For the web-article Henri Gaud simply took a picture of the autochromes on a lightbox with a digital SLR. Since the colour mosaic of the autochrome is at random, in principle no moiré effect should occur with the Bayer pattern in the digital sensor ... but who knows !
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Additional info : references to J.P. Gandolfo's work on the subject
In English : Lavédrine B., Gandolfo JP, The autochrome process, from concept to prototype, History of Photography, summer 1994, p 120-128.
In French : Lavédrine B.,Gandolfo JP, "La plaque autochrome, histoire, conservation et reproduction des plaques additives Lumière", Conservazione dei materiali librari archivistici e grafici, Umberto Allemandi, Aoste, 1999, p 247-256.
There is an on-line article in French on the subject by Anne Cartier-Bresson and Marsha Sirven
http://www.paris-france.org/musees/a...rtellemont.htm
The authors confirm that the violet dye is the most fragile and that autochrome plates should be stored in darkness.