November 7, 2017

How It’s Made: Duochromes In Development

Duochrome film creates two-tone photography, with a twist, and made its debut in our online shop last week in two essential editions: Pink & Black, and Blue & Black. In this interview with our Chief Technology Officer Stephen Herchen, we discuss the creative chemistry developing behind-the-scenes and the work that went into perfecting these editions. Plus, we showcase some of the experimental images captured using the new film.

Photo: Rayan Nohra
Photo: Danny Pemberton

Can you outline the research & development process for creating duochrome film?

To create a duochrome film we must first carefully replace the standard B&W developer paste that is contained within the pod with a colored pigment. This then tints the white in the image that is produced. The R&D process for this involves sourcing pigments that have the desired colors and that have several other required properties. We have to be careful that pigments do not affect the B&W imaging chemistry and sensitometry. They must remain in the paste layer and not migrate into the receiver sheet during development. They must be stable in the resulting duochrome print and not cause any defects in the final prints.

Does the structure differ a lot chemically to our other film?

The structure of the duochrome film is closest to that of our standard B&W product. The main difference is the addition of the tint pigment to the developer paste in the pod. The duochrome film is produced by adding a careful blend of a specially-designed pigment to the developer paste – altered accordingly depending on the desired color.

Photo: Faith Silva
Photo: Brock Fetch
Photo: Brock Fetch

Can you tell us about any difficulties you overcame whilst developing the duochrome film?

Some of the colored pigments tested caused instability of the white titanium dioxide pigment that is in our standard B&W developer past. This instability was visible as defects in the prints. Some pigments migrated into the receiver sheet causing the blacks in the image to be heavily tinted rather than just the white parts of the image. Some pigments were unstable to the final pH of our system so that the tint color faded away with time. We had to work to find pigments that did not have these issues – luckily, we did.

What’s the most exciting part about developing more experimental film?

Our instant film are very chemically complex but this complexity offers great opportunities to be creative. Much of what we do is aimed at getting our film to be more instant and capable of capturing images more accurately. These experimental film are fun to work on because in some cases we don’t know exactly what will happen when we make certain chemical changes until we do the experiment. Because our system is an instant film we get almost immediate feedback and the results can be quite surprising sometimes.

Photo: Catherine Edwardina
Photo: Raymond Van Mil

This film is more difficult for creative techniques, for example emulsion lifts, as they dye runs off easily in the water. Is there a way to overcome that issue?

There is no easy solution for this since the emulsion lift separates the image layers in the receiver sheet and the pigments are confined to the paste layer in the image and for the most part are pretty water soluble. It might be possible to get the pigment to bond more to the image receiver sheet so that the emulsion lift would still contain the pigment color. We would be interested to hear feedback about photographer results.

Any tips for our instant shooters on how to get the most out of this film and how it responds to light, temperature, and care?

Due to the similarity in the chemistry, we would recommend shooting the film in the same way you would do with our B&W film. It is best to allow the prints to dry out naturally as opposed to preventing dry out by doing things like putting them in a ziplock bag. As with all our film during the sensitive first few seconds, make sure the film shield installed on your camera extends on top of the photo and protect it from light.

Photo: Faith Silva

Feeling inspired? Pick up packs of our new duochrome film here: www.polaroidoriginals.com/collections/duochrome-film-for-polaroid-600-cameras