Category Archives: Tutorials

Experiments with the chemigram process, part 2

The first part of this blog post looked at the use of honey, artists varnish and masking fluid as resists, along with use of cardboard stencils. This second part will consider two further resists and a method of creating a “stamp” for printing.

Wood varnish resist

After the disappointment of the artists’ varnish, some traditional exterior wood varnish was picked as a possible resist. The varnish is very thin, so after it was applied to the paper all the brush stokes just disappeared in a matter of seconds, resulting in a perfectly even coating. Once again Ilford multigrade RC paper was chosen, combined with Fotospeed fixer and Caffenol-C-H-UK. The varnish dried overnight for about 16 hours total resulting in a fairly tough finish on the paper. Since there was no texture in the varnish resist, it was decided to intentionally damage the resist. For one of them, a compass and blade were used to create circular arcs across the paper. For the other a series of horizontal and vertical lines were made with a knife.

Wood varnish resist applied to paper. When try, varnish was scored with a compass and blade to form circular arcs

Wood varnish resist applied to paper. When try, varnish was scored with a compass and blade to form circular arcs

When immersed in the chemicals, the varnish resist proved very resilient and non-porous. The places where the resist had been scored with a blade allow the chemicals to penetrate by a tiny amount. After 5 minutes in either the developer or fixer, the varnish showed no sign of disintegrating, so it was decided to try rubbing the resist where the cut marks were. With some hard work this gradually exposed more paper to the chemicals. After going back & forth between developer and fixer a couple of times, the alternating bands of black & white started to appear. A problem that occurred was that the emulsion on paper started to peel up in places where the varnish had been cut, as the cut had penetrated into the paper too. Removing the large extents of varnish proved very difficult indeed – using the friction between rubber gloves and the varnish was the only way and it took about 30 minutes for an ~6×4 inch print.

Wood varnish applied to the paper as resist, and left to dry for 24 hours. Lines scored in the varnish with a blade

Wood varnish applied to the paper as resist, and left to dry for 24 hours. Lines scored in the varnish with a blade

The second sheet with the straight cuts rather than circular arms worked in much the same way. One interesting difference was that some of the areas exhibited a slightly purple tint, possibly where the developer only had a brief chance to work, before being fixed. Again there was a problem with the paper emulsion peeling up. Overall the graphical results of both images were very attractive, clearly showing the tell tale light & dark bands where the resist gradually came away. An easier way of working with the varnish may be to not let it completely dry – perhaps leave it to dry just enough that it no long runs off the paper. That may allow the developer & resist to penetrate more quickly.

Stamps

Following on from the idea of applying the developer to the paper selectively, it was decided to experiment with creation of a simple stamp to imprint an image on paper. For this purpose a piece of 5mm foam board was cut to size, to roughly match that of the paper. There needed to be some material applied that would absorb the developer. For this purpose some lengths of ordinary household string were superglued to the foam board.

String spiral stuck onto foam board to act as a stamp for applying developer to the paper.

String spiral stuck onto foam board to act as a stamp for applying developer to the paper.

String trails stuck onto foam board to act as a stamp for applying developer to the paper.

String trails stuck onto foam board to act as a stamp for applying developer to the paper.

As can be readily seen from the images above, the designs are very simple / crude, just enough to examine whether the general concept is workable. This time Fotospeed print developer was used instead of Caffenol, and it was painted onto the string with a brush. The board was up-ended to allow any excess developer to drain off before it was turned upside down and pressed down onto the paper. The stamp was left in contact with the paper for about 60 seconds.

Print resulting from application of developer to the string spiral stamp.

Print resulting from application of developer to the string spiral stamp.

Print resulting from application of developer to the string trail stamp. Some gaps in the image due to warped board

Print resulting from application of developer to the string trail stamp. Some gaps in the image due to warped board

The results are pretty much as expected. The places on the paper affected by the developer were fairly tightly controlled. There were some gaps where it didn’t make good contact with the paper, mostly due to fact that the foam board was slightly warped. With a well made stamp, the general approach could allow for reasonably detailed figurative images to be created.

Flour paste resist

For the final experiment another type of resist was tried out. Taking a small quantity of regular baking flour, water was slowly added until a thick paste was formed. Two sheets of expired Ilford FB paper were then coated as evenly as possible with the resist and left to dry. As should be expected from fibre based paper in contact with water, it curled up hugely when the paste was applied. The flour paste resist was left to dry for 24 hours, during which time the surface started to crack up slightly

Expired Ilford FB paper covered with flower resist and allow to dry and crack.

Expired Ilford FB paper covered with flower resist and allow to dry and crack.

The theory behind the use of a flour paste, was that the once dry it would provide a relatively hard & well attached resist, that would none the less dissolve fairly easily in the developer/fixer. The dried papers were placed alternately in the developer and fix baths for a couple of minutes at a time. Gentle rubbing was used to encourage the resist to dissolve and come away from the paper. Flexing the paper also encouraged further cracks to form in the resist which allowed the chemicals to work their magic. At times moderately large lumps of flour could be detached from the paper.

Image created from dried flour and water resist.

Image created from dried flour and water resist.

Image created from dried flour and water resist.

Image created from dried flour and water resist.

The results of the flour paste resist were quite satisfying. The distinct channels / lines in the image come from where the dried resist had cracked up. There was a reasonable degree of control over the image thanks to the ability to gently prise off chunks of the resist where needed. There was clearly still a very high degree of randomness involved in the images though, so rather than saying the process was controlled, it is perhaps better to say it was just influenced. The images apear to bring to mind the idea of organic cellular structures.

The two resists illustrated in this part of the blog were both much more successful than those from the first part of the blog. The wood varnish and flour paste were both very effective in the way they allowed interesting images to form, but the results have very different characteristics and the way they were worked in the chemicals was very different too. These results clearly show the importance of choosing the right type of resist to achieve the desired graphic effect on the final image. Experimentation and an open mind is key, because it appears hard to predict how any individual substance will perform in the real world.

With a set of experiments out of the way, now it is time to move on and attempt to create some presentable works of art.

Experiments with the chemigram process, part 1

The previous blog post introduced the chemigram process, a means of creating images using photographic materials to write with chemistry instead of writing with light. This post will examine some of the initial experiments personally undertaken to explore and gain an understanding of the process.

Honey resist

For the first attempt at making chemigrams, I used Ilford Multigrade RC paper, and covered it in a resist of set, but still easily spreadable, honey. I applied the honey with a kitchen knife and attempted to smooth it out as much as possible over the entire sheet of paper. None the less it was still a fairly uneven thickness. Fotospeed FX30 odourless fixer was paired with Caffenol C-H-UK developer and water stop bath. It immediately became apparent that caffenol is not the best choice of developer for chemigrams. Functionally it worked just fine, but practically it was a pain as the opaque brown colour prevents the changes in the chemigram being visible without removing the paper from the dev. Still, we must work with what we have at hand, and that happened to be caffenol this time.

The paper was switched back and forth between the developer and fixer, allowing anywhere between 30 and 120 seconds in each chemical at a time. The honey resist proved fairly stable, adhering to the paper well and gradually dissolving over about 10 minutes. There was little need to agitate the trays nor to manipulate the resist.

Chemigram with a resist of set honey.

The darker black and pure white areas seen at the edges and just below center were a result of the paper being exposed to the developer and fixer for their nominal processing time (~120 secs). The paler grays and dirty whites were a result of shortened exposure to the chemicals (~30 secs). The alternating bands of dark and light clearly illustrate how the resist was gradually dissolving while being switched between chemical baths.

Artists’ varnish & masking fluid resist

In a visit to the local art supplies store, I discovered a variety of different products that could serve as resists for the chemigram process. A random choice resulted in the acquisition of a bottle of Windsor & Newton Artists’ Acrylic Matt Varnish, and a bottle of Windsor & Newton Colourless Art Masking Fluid.

Artists varnish and masking fluid, to be tested as potential chemigram resists.

Artists varnish and masking fluid, to be tested as potential chemigram resists.

Once again some Ilford multigrade RC paper was used, three pieces were coated with the varnish and three pieces were coated with the masking fluid. In all cases the fluid was applied using a small paintbrush, but to investigate the effects of brush stroke pattern on the final image, different patterns were used when applying the fluids. In one the brush strokes were diagonal, in one they were horizontal and in the other they were completely random swirls. Interestingly there was an immediate effect on the colour of the paper – masking fluid turned it immediately blue while varnish turned it immediately pink. Neither colour would ultimately persist in the final image, so this difference in behaviour doesn’t appear to have a practical use.

Papers coated with artists' masking fluid (left hand column) and artists' varnish (right hand column)

Papers coated with artists’ masking fluid (left hand column) and artists’ varnish (right hand column)

Once the resists were dry (only a matter of an hour or so) they were intentionally damaged. On some of the sheets of paper I used a knife to score some straight lines across the resist, while on others I used a compass with blade attachment to score some circles / arcs. The varnish was easily penetrated by the blade without applying any pressure. The masking fluid resist was slightly more difficult to score as it had quite a rubbery texture when dry – a sharp blade was required. Even now the rubbery dried masking fluid would come off the paper without much effort if rubbed.

As before the chemicals were Fotospeed fixer and Caffenol-C-H-UK developer. The sheets of paper were fully submerged in the chemical baths at each step, going back and forth several times. The artists’ varnish resist did not have much permanence, dissolving and flaking off in the chemicals very quickly. The image was almost entirely based on the pattern of the brush strokes used to apply the resist – scoring the mask had no perceptible effect. The developer appeared to penetrate the resist depending on its thickness to darken the image and the fixer removed the rest of the resist.

Windsor and Newton Artists' Acrylic, Matt UV varnish resist. The only texture shown in the image matches the brush strokes of the resist. The chemicals penetrated the resist quickly and it dissolved & flaked off before any alternating bands would form

Windsor and Newton Artists’ Acrylic, Matt UV varnish resist. The only texture shown in the image matches the brush strokes of the resist. The chemicals penetrated the resist quickly and it dissolved & flaked off before any alternating bands would form

The resist using masking fluid was somewhat more satisfactory. It did not appreciably dissolve in the chemicals, not did they penetrate through the resist. The chemicals could work on the paper in areas where the resist had been scored with a blade. Rubbing on the resist would cause the rubbery mask to come away from the paper, though a gentle touch was needed otherwise massive amounts of resist would come loose in one go.

Windsor and Newton masking fluid resist, with circular marks scored into the resist with a compass and blade

Windsor and Newton masking fluid resist, with circular marks scored into the resist with a compass and blade. Developer was first bath, hence black border

Windsor and Newton masking fluid resist, with straight lines scored by a knife.

Windsor and Newton masking fluid resist, with straight lines scored by a knife. Fixer was first bath, hence white border.

Overall the artists varnish proved a disappointment, while the masking fluiding showed some hints of promise when damaging it with a knife. The ease of removal of the masking fluid when the image was finished was particularly appealing.

Stencils

For this experiment, instead of using a resist to control the action of the chemicals, it was decided to make a stencil. A piece of 3mm thick fibre/cardboard was used for the stencil and various circular holes were cut using a compass fitted with a blade. In addition, some pinprick holes were made randomly in the card

Piece of cardboard with spheres cut out to act as a stencil for applying developer/fixer to paper.

Piece of cardboard with spheres cut out to act as a stencil for applying developer/fixer to paper.

For its first use, developer was chosen as the chemical to paint in through the stencil. This resulted in a predominantly white background, with areas of black where the developer was painted. From the results it can be see that the developer soaked into the cardboard and run underneath the edges, so the outline on the image is far rougher than the stencil. There is an attractive highlight around the edges of the circles though – this appears to be something to do with the ineraction of the surface tension of the developer and the edge of the stencil.

Cardboard stencil was placed on to the photo paper and developer painted into the holes. Developer washed off and then image fixed.

Cardboard stencil was placed on to the photo paper and developer painted into the holes. Developer washed off and then image fixed.

For the second use of the stencil, the fixer was picked as the first chemical to apply. The cardboard was fairly contaminated with developer from the first usage, which no doubt had an impact on the effectiveness of the fixer. The fixer was not left to act for long enough either. When the print was moved into the developer bath to form the background, even the areas exposed to the fixer initially darkened.

Cardboard stencil was placed on to the photo paper and fixer painted into the holes. Fixer washed off and then image placed in developer, followed by a bath in fixer.

Cardboard stencil was placed on to the photo paper and fixer painted into the holes. Fixer washed off and then image placed in developer, followed by a bath in fixer.

The stencil idea is promising, but further investigations are needed to identify a more suitable material to use as the basis of the stencil. At the very least a less porous form of cardboard seems necessary. Alternatively it might be interesting to the use the stencil as a mask for the applying the resist, instead of directly applying the developer/fixer.

In the next part of the blog post, some further types of resist will be illustrated along with a method of creating a “stamp” for printing with chemicals.

An introduction to the Chemigram process

The chemigram process is an artistic technique that involves the use of photographic materials and chemicals, but counter-intuitively will not generally be classified as a photographic process. Considering a fairly broad interpretation, photographic processes involve the formation of images by exposing some kind of sensitive emulsion to light. This may involve use of a camera, or may be entirely camera-less, but it is still “writing with light” as the formation of the image is dependant on the amount of light reaching each discrete point on the paper. As chemigrams are commonly (but not required to be) created in conditions of normal daylight, the photo-sensitive emulsion will be fully saturated by light almost immediately. It follows that the image formation is not based primarily on exposure to light, and thus precludes its classification as a photographic process.

Chemigram 1.8 olive oil resist, by Carol Shergold, licensed CC BY

Chemigram 1.8 olive oil resist, by Carol Shergold, licensed CC BY

The basic idea of a chemigram is that photographic paper is alternately & repeatedly exposed to both developer and fixer. Areas of the paper exposed to developer first will tend towards black (since the paper is fully saturated with light), and areas of the paper exposed to fixer first will tend towards white. Obviously if a plain sheet of paper is placed in a bath of developer the whole sheet will go black which won’t be too interesting. So the technique involves some method of influencing which areas of the paper get exposed to the chemicals at each step, thus forming the desired image. As such the process is best described as “writing with chemistry”.

The chemigram process was invented and pioneered by Pierre Cordier, who sub-divides the practice into three categories:

  1. Chemigram without resist. The developer / fixer will be applied directly to the paper, using paint brushes, sponges, etched plate, stencils, stamps or any number of other instruments. This technique takes the chemigram close to traditional painting practices. Pigment based paints have simply been substituted for photographic developer & fixer.
  2. Chemigram with resist applied by hand. The paper will be coated with some kind of product that resists the effects of the developer and fixer. As the paper is passed back & forth between the developer and fixer, the mask will gradually come off allowing the chemicals to form an image.
  3. Chemigram with resist applied by photographic process. Again the paper will be coated with some kind of resist, but in this technique the resist will be applied using some photographic process such as silk screen printing with photo emulsion. This takes the chemigram close to traditional photographic practices.
Prayer to the sun

Prayer to the sun by Balazs Sprenc, licensed CC BY-NC-ND

The variables

As with any artistic process though, there are no strict barriers – elements of each of the three categories can be applied in the same image if desired. For example an initial part of the image can be formed by painting developer/fixer onto the paper using a brush. Once that is completed, a resist can be applied to the remainder of the paper and further developed/fixed. The chemigram technique could also be combined with regular photographic processes such as photograms / lumen printing at the artists discretion. There are an immense range of factors that can be varied to influence the resulting image. A non-exhaustive list would include

  • Type of paper – resin, or fibre based, which manufacturer, which variety, fixed grade, or multigrade, etc. Any photographic darkroom paper ever produced is a candidate for use with the technique.
  • Age of paper – if you have a box of expired paper from 1960, don’t overlook it. Since the chemigram is commonly created in broad daylight, fogged paper is not a problem to worry about.
  • Type of resist – any product which will adhere to the paper even for a mere second, whether it be varnish, paint, masking fluid, honey, flour paste, egg, clay, butter, or wilder ideas
  • Additions to the resist – no need to stick with the basic product – if honey is too thin, add flour or sugar to thicken it up. If the resist is too transparent to see, add some dye / food colouring. The resist sticks too well, mix it with something that’s more soluble.
  • Application of resist – the resist applied with fingers, knife, brush, spray, stencil, roller, sponge, quill, etc. The tool used will affect the surface texture of the resist, which in fact can affect how evenly the chemicals penetrate the resist. For example, brush strokes left in the resist may transfer to the paper if the resist is porous to the developer/fixer.
  • Resist drying time – the length of time a resist is left to dry will affect how easily it comes off in the chemicals. Leave it the minimal time to adhere to the paper, or until it is 100% dry and hardened, or anywhere in between. The harder the resist has set the slower the chemicals will penetrate it, giving more time to work the image.
  • Ambient lighting conditions – while normal daylight is most common, a darkroom could allow for localized light exposure and/or combination with other photographic techniques. For example the paper may be initially contact printed, and then a resist applied over part of the image, letting the uncovered image fix immediately.
  • Area of paper with resist – the resist does not have to be applied evenly to the entire paper. Specific areas can be covered by resists, or left uncovered.
  • Damage to the resist – once coated the resist can be intentionally compromised to allow the chemicals to penetrate more easily. For example a knife can be used to cut through dried varnish. Or paper can be bent to crack the surface of hardened resists
  • Chemical types – different brands or mixtures of developers and fixers have different effects on the tones exhibited by the paper. If regular dev is not doing what you like, you can even try lith developers.
  • Chemical strength – more concentrated developer/fixer will speed up the process which may save time. Conversely less concentrated solution allow greater time to finesse the image
  • Toners / dyes – as with any photographic print, toner / dyes can be applied to adjust the colour of the final print
  • Time in the baths – the time spent in developer / fixer before switching to the alternate bath will determine how much time it has to penetrate the resist and bring out the tones of the paper. To get tones in between black and white, leave the print in the chemicals for less time, so the fixer/developer has not fully taken effect.
  • Application of chemicals – the developer / fixer can be applied by dunking the prints in trays, or it can be applied directly to the paper using a tool, such as brush, sponge, etc. The latter would allow for much more localized control of the image formation.

Any analogue artistic process will result in unique works, but with some processes it is practical to create editions of work that are fairly close to identical. This is particularly true of techniques that involve an element of printing whether photographic or not. This is not the case with chemigrams, especially when resists are used. There is a very strong element of non-deterministic behaviour in the creation of chemigrams with the result that even if the exact same steps are followed each time, each final image is likely to be considerably different. There is little scope for creating an edition of identical prints in the strictest sense – at best you will get a family of related works, each with their own distinct character and qualities.

Draco, by Nate Lawson, licensed CC BY-NC-ND

Draco, by Nate Lawson, licensed CC BY-NC-ND

The equipment

Getting started with the chemigram process is remarkably straightforward, with little equipment and no darkroom required. The minimal setup would consist of 3 darkroom print trays, a 1 litre measuring jug, a bottle each of black & white developer and fixer and a packet of black & white photographic paper. The print trays, jug and B&W paper are easily found on ebay, as many people are selling off old darkroom equipment for next to nothing – 15 pounds for all those items would be easily attainable. There’s no need to worry whether the paper is outdated, or fogged, as chemigrams are usually created in daylight. The developer and fixer can be obtained online from a couple of suppliers in the UK for no more than 10 pounds each for 1 litre bottles.

The process

To start off mix up 1 litre of developer at the recommended dilution (typically 1:9) and pour it into one tray. Do likewise for the fixer and pour it in the second tray. Put a litre of tap water in the third tray. The temperature of the solutions in each tray should be approximately 20C but accuracy is not important for this process – changes in temperature will merely affect the speed of the process. One could use stop instead of water for the third tray, but again that isn’t too important – both the developer and fixer will get so badly contaminated with the residue from the resists that they’ll be disposed of before cross-contamination becomes a significant issue.

Assuming you intend to only ever use the paper for chemigrams, you can take sheets straight out of the lightproof black bag in daylight. If you ever want to use the pack of paper for real darkroom work though, make sure you have a changing bag or some other means of removing sheets of paper in the dark, to avoid fogging the remainder of the pack.

Take a sheet of paper and apply whatever product you wish to use as resist. A good place to start is with something that is soft, spreadable and sticky – thick honey, syrup or mustard. Coat the paper completely, or just partially, as you wish. Then place the paper into either the developer or fixer tray, again it doesn’t matter which. Let the paper soak for an arbitrary amount of time. If desired, physically rub away at the resist a little, or just let the chemicals slowly dissolve it. Then take the paper out of the tray and put it in the plain water tray to wash off chemicals. Once washed, put the paper into the other chemical, and again rub the resist if desired. Repeat this, switching between the developer and fixer each time. Either continue until all the resist has gone away, or stop sooner and just wash the remaining resist off the paper. When all resist has gone, put the paper into the fixer for a final time. With the final fix done, wash the print in a fresh bath of water for as long as is needed for the type of paper being used to remove all trace of chemicals.

The story of nine dots

The story of nine dots, by Balazs Sprenc, licensed CC BY-NC-ND

The rest

A mentioned earlier, the process was pioneered by Pierre Cordier and he is still probably the most well known practitioner. There was a rare exhibition including some of his work at the Victoria & Albert museum in 2010/2011, for which there is an associated video worth watching online. For a range of articles looking at contemporary artists using the chemigram technique, the extensive nonfigurativephoto blog is worth reading.

The images in this posting are creative commons licensed chemigram works from a couple of flickr users. In the next blog posting I’ll present some of my own initial experiments with the chemigram technique.