Back
 
 

 The following article was sent to me a few years ago. I do not know its date of publication, but I thought it might still be of interest to a few of our readers.
--- Joe Besse

MEDIOBROM PROCESS
by Barbara Green, FRPS, FPSA

(Another use of oils on photos, this technique is a stand-by of prize-winning pictorialists)

Mediobrom is a fancy word, but the process is a simple one. It sounds difficult--but it's just a method of balancing and enriching a print by applying and removing the oil paints used by artists.

Why mediobrom? Because we don't always pull a perfect print from the hypo. It may have been printed in--but not enough. It may be too contrasty. It may be weak in tone. We could chalk the light areas, but we can go much further in altering tones, with the mediobrom process. As with the chalks, probably you can buy what's needed in your local art store. If not, Joseph Torch, 147 West 14th Street, New York 11, N.Y. has the following in a Mediobrom Kit, at a price of $3.90 plus postage:

2 1/2 oz. rectified turpentine

2 1/2 oz. purified linseed oil

2 1/2 oz. white Japan dryer

1 studio tube ivory black oil color

1 single tube cobalt blue oil color

1 single tube cadmium red oil color

1 single tube Paynes gray oil color

1 kneaded eraser

1 pencil point eraser

1 white metal palette-dish

1 #3 Windsor Newton sable brush

In the drug store, buy some Q-tips, an eye dropper and a half pound of non-sterile cotton (half the price of the sterile, which is important, as you'll use more of this than any other item on the list). Skimping on cotton can mean a messy print.

Have you found a print where the highlights need subduing-- the shadows darkened--or the sky toned down? Do the necessary spotting first, as it's easier now than after you've medio bromed. But do not etch out dark spots, or pinholes, before mediobroming, as any abrasion in the paper will quickly pick up the paint. Work by daylight, if you can. But whatever your light face it--so You'll have no shadow on your print. Start by placing the kit plus a piece of heavy cardboard, or a Masonite (larger than the print) on a table. Fasten your prints to the board with scotch tape, along the margins. Be sure your print is absolutely flat and dry.

Step No. 1 is to prime the print. This can be omitted, if you have just a few small spots to mediobrom. Then you can get by with applying the paints directly to the print. But if you're apt to work on more than half the picture, it's best to make a habit of priming. The object is to give the paper a "tooth." That's why you can't chalk or mediobrom a glossy paper--the surface won't allow the medium to sink in. The rougher the surface, the better the paint will take hold.

We start by pulling off two or three pieces of cotton and wadding them into a sort of ball (so that the cotton won't be loose and fluffy). Take the bottle of linseed oil (some people successfully use megilp) and, covering part of the opening with your finger, shake some of the oil over the entire print--as you would when cleaning glass. With the wadded cotton, rub the oil into the paper, covering it evenly, with a constant, circular motion. Go over the print with two or three pieces of cotton (a) so that the oil will be rubbed in thoroughly, and (b) so that you won't have any excess of oil on the surface. Now, set your print aside, while you prepare for Step No. 2.

No one can write a formula for blending oil colors. But you'll soon know what you get from the addition of one color to another. With a little practice, you won't find it difficult to match the paint to the tones of your print. Incidentally, that's one of two reasons why it's a good idea to cover the margin with the paint: besides being able to feel it to see whether the paint is dry, you can tell from the edges if you've done a proper job of matching color.

Ivory black is the basic color for black and white, or sepia prints. As it's a brownish-black, you can often use it alone, on warm-toned prints. Your print is browner? Add a speck of cadmium red. Blacker? Try a bit of cobalt blue. Paynes gray is the basic color for blue-toned prints, but you may have to blend in a touch of cobalt blue, or ivory black, or both.

So, we'll squeeze about an inch and a half of the basic color into the palette dish. With the eye dropper, add about five drops of the Japan dryer. Mix this thoroughly with a small knife; then deposit a piece the size of a pea on a corner of the palette. Some undiluted pigment often comes in handy, later. To the rest of the mixture, add five drops of artist's turpentine, and blend. The paints are mixed fresh every time you use them, for if they stand, they harden. Now, moisten the clean, wadded cotton with the paint mixture and put some on the margin. It matches? Good; then you're ready for Step No. 3.

This step will horrify you, because you'll be sure you've ruined your printl But don't worry, mediobrom can be removed at any stage--even after it's dried. Rub over it with turpentine;

it's easy as that. If the paint's still wet, linseed oil alone will take it off. So, after matching the tone in the margin, you smear the entire print. Pay no attention if it's too light or too dark in any one area. You can fix that, later on. Just rub and rub and rub, with the good old circular motion, with two or three pieces of cotton, at least. Don't be afraid to rub it in thoroughly. Now, with fresh cotton, smooth it down. Remember, this is really a reversal or elimination process. As the whole print has been darkened, you decide which parts of the highlights or the shadows you'd like lighter. You simply rub a little harder over that area, with still more cotton. You rubbed off a bit too much? Just add more paint to that spot. Should a tiny spot need darkening, pick up a little of the undiluted paint, with your #3 brush. Wipe off any excess, on the palette, so that the brush is quite "dry." Holding it over the spot, apply the paint with a "bird-pecking" motion. Always brush lightly over lightened outlines with clean cotton, to "feather" or soften them.

The pencil eraser points up highlights. Clean it on a piece of cloth, after every daub. For still smaller accents, pull a piece off the kneaded eraser and roll it into a point the size of a pin, for a catch-light, or a whisper of a line. Touch it once to the print, then fold it under and make another point--or, throw it away. Otherwise, you'll be depositing paint, instead of removing it! And, unless you want a palm print for the FBI, keep a piece of paper under your hand, when you work with the brush or eraser.

With Japan dryer added to the paint, a print may dry in 24 hours--but it's much safer to give it two or three days. Then, it's ready to be waxed. Should you wax too soon, you may remove the mediobrom--and have to begin all over again.

To produce a sparkling and balanced print, you shouldn't have to mediobrom. You shouldn't have to take aspirin, either. But when the photographic headache of trying to save a print hits you, you'll be glad to reach for the mediobrom kit on your darkroom shelf.

And mediobrom is a way to achieve a new end in photography. With this technique, you will arrive at effects not available through the straight-forward use of the camera.

 
 

Back