Bromoil process
Bromoil print on Kentmere document art paper. Graphic black litho ink.
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I began my photography as a youth in 1957 and around that time I was inspired by some beautiful tricolour bromoil transfers made by the president of the local camera club. He was kind enough to give me a demonstration and I did try some single colour transfers using sheet film as the matrix. He used an old clothes mangle with large wooden rollers as a press, but I only had access to the electric rollers on my mothers washing machine and after several trapped fingers, and my father asking questions about how ink had got on to his white shirts I gave up the idea. I did try making several bromoil prints but back then I was more attracted by the transfer process and didn't keep it up. I was recently inspired by some wonderful bromoil images I had seen on the internet, and maybe it was a natural progression for me from gum printing to bromoil and also I thought it would be good to work from my medium format negatives using a conventional enlarger. I am still very much a beginner in this process, but perhaps a description of how I got started and made the prints which illustrate this article may be useful to someone else who is interested in making bromoil prints.I will provide some links to one or two other sites of interest and suggest books for further reading. Briefly, the Bromoil process is based mainly on the simple fact that oil and water do not mix. A bromide print is made which is processed in such a way as to avoid hardening the gelatine emulsion. This print is then bleached in a tanning bleach which hardens the gelatine proportional to the ammount of silver deposited in the emulsion, this print is then termed the matrix. After drying this matrix is soaked in water at ca 20' C for about 10 to 20 minutes, during this soak the hardened gelatine in the dark areas of the print does not swell as much as the unhardened gelatine in the lighter tones, which will swell absorbing water and will therefore repel greasy ink, while the unhardened gelatine will accept it. Having said this I do not intend to discuss any theory, but to just describe how I made my first bromoil prints and my method of working to date. |
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Kentmere document art paper graphic black litho ink |
I made my first bromoil prints using Kentmere document art paper, this is a non supercoated paper and as such is well suited to the process. However, of the modern papers Agfa multicontrast classic fibre base semi matte (118) is highly recommended by several sources and the print of Whitby harbour I made on Ilford multigrade lV fibre base matte. The bromide prints should be on the dark side, have plenty of shadow detail and tone in the highlights. The prints on Kentmere paper which inked up the best were about a 1/4 of a stop darker than I would normally make them. I made several prints of the Whitby harbour negative on Ilford multigrade lV and the one which inked up the best was made about 1 stop darker and 1 grade softer. All the prints were developed in Ilford Bromophen diluted 1+8 for 2.5 minutes at 20'C. The stop bath was Jessops econostop at normal dilution. It is necessary to use a non hardening fixer and the usual recommendation is a 10% solution of plain hypo ( sodium thiosulphate ). However, as complete washing is required to prevent overall tanning at the bleach stage, I used an archival method devised by Ilford. This involves fixing for 1 minute in Ilford hypam rapid fixer at the film dilution of 1+4, washing for 5 minutes, 10 minutes in Ilford wash aid and a final wash of 5 minutes. This assumes a temperature of 20'C, so if your wash water is colder than this then the wash times should be extended. The short fixing time and use of a wash aid greatly facilitates the removal of residual chemicals during washing. |
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The next stage is to bleach/tan the bromide prints, I used the following formula. distilled water...............................................................750ml copper sulphate............................................................30g potassium bromide........................................................30g potassium dichromate.....................................................2g distilled water to make....................................................1litre For use dilute 1+3 with distilled water. It is important to use distilled water as tap water contains too many impurities. One litre of working strength bleach will bleach/tan ca 10 8x6 images on 10x8 paper.The prints should have been properly dried after fixing and washing before bleaching. I bleach my prints for 8 minutes at 20'C to ensure tanning is taking place as well as bleaching, wash for 15 minutes, potassium metabisulphate bath (25g/litre) to remove dichromate stain, wash 5 minutes, fix in Ilford hypam 1+4 for 1 minute, wash using the same washing procedure as detailed above and dry. |
Ilford multigrade lV fibre base matte paper graphic black litho ink |
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Kentmere document art paper graphic black litho ink. Afterwork carried out with a pencil point eraser and graphite pencil. |
The dry matrix now has to be soaked in water to swell the emulsion ready for inking. all the bromoils used to illustrate this article were soaked for between 10 and 15 minutes at 20'C and inked up using graphic black litho ink 1796 which had been stiffened with oil pastel or crushed magnesium sulphate (epsom salts). The relationship between soaking time and temperatureand theconsistency of the ink is a key factor, The greater the swelling the thinner the ink needs to be. Either the degree of swelling is suited to the consistency of the ink or the consistency of the ink can be suited to the degree of swelling, a factor which is determined by the individual and experience. After soaking drain the matrix and place it face down on a blotter and wipe all traces of moisture from the back with a paper towel, then turn over the matrix and blot dry the gelatin surface making sure that no traces of water can be seen on the surface. All the prints here were inked up using pastry brushes and a shaving brush trimmed to a stag foot shape with scissors. Take portion of ink about the size of a pea and spread it thinly with a pallet knife onto a ceramic tile. Dab the brush into this thin layer of ink two or three times, then dab onto a clean area of the tile 20 or 30 times to evenly distribute the ink on the brush. |
| Begin applying the ink to the matrix with gentle dabbing motion, recharging the brush with ink as required until all the matrix is covered, at this stage the image will look quite flat and dull. Then without recharging the brush continue to work on the image using a more vigorous pouncing action which should begin to clear the highlights.At this point resoak the matrix for a few minutes, blot dry and continue with the second brush action without adding any more ink to the brush, or using a clean brush. The highlights should now begin to clear and the contrast will build up. With successive soaking and reworking with the brush the midtones and shadows can be opened up. If the ink does not take in the highlights it can be thinned by adding a small ammount of unstiffened ink ( about the size of a couple of pin heads ) or a drop of linseed oil applied with a toothpick. The progress of the inking procedure is difficult to describe, the best way is to do it, this is the only way to learn by doing it again and again and you will be surprised how quickly you will catch on. |
Kodak Ektalure paper graphic black litho ink |
This has not been in any way an in depth article on making bromoil prints, but a description of how I made the prints in the illustrations and my working method to date. This will no doubt change with time as I gain more experience with the process, but I hope there is enough information here to get you started with the process.
For further reading :' Bromoil 101' by Gene Laughter is an excellent working guide and practical manual which contains a full working description of the process as well sections on making your own brushes, preparing inks, contemporary papers and print finishing. Available from Bostick and Sullivan. For some theory and a history of the process try 'History and practice of oil and bromoil printing' by Luis Nadeau. The reading room on the international society of bromoilists site has a number of articles and books available for downloading as pdf files.
Links
International society of bromoilists
Gryspeerdt and the bromoil process
Bromoil prints by Gene Laughter