The Oil Pigment Process

Progress, Volume VI, Issue 12, 2 October 1911, Page 824

The Oil Pigment Process

E. Warner.

There are many methods of using the oil pigment process. The following is the one that finds favour with most oil workers at home. When this has been mastered other ways and means will no doubt suggest themselves to the enthusiastic "Oiler." A sheet of paper thinly covered with gelatine is the first essential —double transfer carbon paper, the oil paper specially put up by Messrs. Griffin, London — and many smooth and mat bromide papers Wellington & Ward's carbon surface, Ilford Carbon Surface, Kodak Permanent, Griffin's Lingrain, and Barnet smooth. These I can recommend; other papers are perhaps just as good, but I have not tried them. The Bromide Papers require fixing in a clean Hypo, bath and a thorough washing afterwards. The experienced oil worker can get good results from any description of negative, but I strongly advise the beginner to use for his first attempts a wellexposed, lightly developed negative, free from fog, with clean shadows and translucent blacks. Some oil pigment brushes will be required, a tube of black or brown pigment, a quire of fhiffless blotting paper, and a piece of plate glass, rather more than two inches larger each way than the size of paper worked on. The sensitizer used is the Bennett Carbon formula — Pot. Bichromate 4 drams Citric Acid 1 dram Water 25 ounces Ammonia. .880. about 3 drams The pot. bi. and citric acid are dissolved separately in hot water, the solutions mixed and sufficient ammonia .880 added to change the colour from orange red to lemon yellow. The ammonia must be added immediately after mixing the two solutions. If mixed as described the solution will keep indefinitely. To sensitize put sufficient solution in a dish and immerse the pieces of paper required, being careful to remove any air bells and allow the paper to soak for two or three minutes in warm weather, for four or five minutes hi cold weather, then remove the sheets to a warm, dry and dark cupboard. When thoroughly dry the paper is ready for printing. Printing should be carried out in the shade, and as the image is very faint and the paper extremely sensitive, it is advisable to inspect the print in a dark corner of a room. The print is finished when all but the highest lights are visible. The colour of the image should

V«* ! greenish brown, and as this is a difficult colour to judge by, as beginners m 1 latmotype printing know, it may be as well to print m strips, to learn by trial and error as to the exact time to stop printing. This should not prove a dimcult matter, and a trial or two will put the beginner right. _ the paper, as soon as printed, requires soaking in three or four changes of water to remove the bichromate stain, The water may with advantage be just tepid in cold weather. When the stain has quite left the paper place in a clean dish of water for one hour. Now that the gelatine print has been thoroughly soaked, place it on a pad of at least half a dozen sheets of blotting paper, wet, but holding no superfluous

moisture, Best the whole pad on the sheet of plate glass to present an even surface, and proceed to dry the gelatine film. A piece of butter muslin or a handkerchief will do this as well as anything, Roll the material into a pad and dab the surface gently. When the last spot or streak _ of water_ been removed the print is ready for "oiling." Aow take the tube of pigment and squeeze a little _ (very little will do, a piece the size of a small dried pea will cover a lo x 12 print) on to the palette—a spoilt negative answers—and rub down with a knife. Take a medium size brush and dab gently on the pigment, lift the brush and crush it firmly two or three times on a clean portion of the palette, then attack the print. The pigmenting is done with a dabbing action. This can

only be learnt by practice, but very little practice is needed to show the beginner the right and wrong way. Do not be in too great a hurry to get a finished print, Be content to give all attention to a small portion, then, when this begins to show a well graduated deposit of pigment, gradually work over all the print. It will be found best at first to apply as little pigment as possible, and to build the image up gradually. After one or two prints have been produced it will be possible to charge the brush full of colour and apply it to the print in larger quantities. By this method the shadow detail can be built up very quickly and the picture evolved by the removal of superfluous ink by a hopping action of the brush. The latter method is more effective for strong sub-

jects, and gains a spontanity by its rapidity of execution. But the beginner is advised to leave this method alone until some knowledge has been gained by the first and simplest method. A guide print—either a small contact print or a bromide enlargement—will prove of great assistance while the pigmenting is being carried out. Alterations or additions can be indicated on the guide print and will leave the oiler free to give individual attention to the manipulative side of oil printing. When the print is finished and the gelatine surface dry—this usually takes about two hours—the pigment is still in a tender state and now is the time to wipe out any high lights, either with a leather stump or a piece of pointed indiarubber. Should, however, any parts require darkening,

soak the print again in tepid water and pigment locally. By carefully following the above instructions a successful oil print can be made at the first attempt. When the print is finished lay fiat to dry. The pigment will take from one*to three days to dry and until thoroughly dry should not be touched. Brushes must be cleaned with petrol.