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Working in the traditional at-home darkroom

By Ross Collins, professor of communication, North Dakota State University, Fargo.

For those who want to give darkroom work a try, this process hasn’t changed. Nor is it much different in a commercially built darkroom. While the home darkroom may be a lot more, well, rustic, you can emerge with prints fully as high in quality as you’ll find in the commercial darkrooms. All it takes is…a little practice.

Watch the videos!

Development tutorial one. Tutorial One: Developing film in the home darkroom.

Development tutorial two. Tutorial Two: Printing in the home darkroom.

Rolling a film onto a developing reel. Tutorial Three: video demonstration of rolling film onto a developing reel.

Introduction: Roots of photography: the negative and the positive.

Chemical-based images using a negative/positive process date from the very beginnings of photography. While Daguerre’s famous process of 1839 made unique pictures on copper plates, William Henry Fox Talbot (Cambridge grad!) within two years unveiled the negative/positive process that came to dominate the industry.

Light-sensitive chemicals based on silver compounds, such as silver halides, turn dark when exposed to light, as was long known. Should it be possible to make that image permanent, or “fix” the image, a photographer would then have a negative image on paper or any other surface coated with silver halides.

A negative image.Of course, a negative image wasn’t of much use. Daguerre’s technique produced sharp, positive images, and so became the rage from 1839-1851. But the negative/positive process eventually prevailed because it had some big advantages. Negatives produced on clear or translucent surfaces could be pressed against a second sensitized sheet and, when light was projected through, would transfer to a positive image on the paper. This could be repeated. That meant that instead of obtaining a single image from each camera exposure, you could take just one picture and make as many images as you wanted. Secondly, the chemicals used in the silver-based process were less dangerous and fussy. Soon the “speed” of the film—that is, how sensitive the chemicals were to light—increased to the point where you could obtain a decent image in seconds. And not long after that, less than a second.

Daguerreotypes died out after Scott Archer invented a negative/positive process in 1851 using glass plates. Yes, these were bulky and breakable. They required huge view cameras (the famous bellows and cloth). Worse, they were coated with the light-sensitive chemicals in a portable darkroom on site, because the exposure had to be made and processed in a darkroom before the chemicals dried.

Despite this cumbersome process, photographers captured images that included some of the most important scenes of the day. The U.S. Civil War was photographed using the Archer process. So was much of the early American West.

A film for the hobbyist.

But these photographers were invariably highly skilled professionals. Amateur photography barely existed.

By the 1870s inventers such as George Eastman had found ways to produce dry plates. While this was an advance, still, those heavy glass plates and cameras had to be carted from place to place.
Kodak camera.

In 1881 David Houston, Hunter, N.D., received a patent for a roll film holder. He sold that patent to George Eastman of Eastman Kodak, who launched his first roll film camera in 1888. Silver halides were embedded in a gelatin, called emulsion. The emulsion was coated on a flexible plastic-like backing. Three years later Thomas Edison borrowed the idea to create his first motion picture camera.

Kodak’s production of the roll film camera became the most significant advance in photography since 1839. Photography finally became possible for amateurs, while movies based on roll film grew to extraordinary importance in the next century, as entertainment, news, instruction and propaganda.

The quest for dark.

The 20th century became the age of film. But that film was based on silver halides, and so still required a darkroom. Kodak’s offer to process and print film taken by amateurs encouraged growth of photography by dispensing with a need to learn darkroom skills. People merely brought their exposed film to the drugstore or photo shop for processing. Most of this film was black and white. While modern color photography was invented in the 1940s, widespread use of color did not reach the average household until the 1970s. And emulsion-based color processing remained a complicated process. To print color photos required a sophisticated enlarger, expensive chemicals and color photo paper, along with skills beyond most amateur possibilities. (I did use the Cibachrome process in the 1970s to early 1990s. It easily produced brilliant color prints from slides, but it was expensive and slow. It still lives (barely) today as Ilfochrome.

Photo buffs were not satisfied with commercial finishers, however, as they had no control over the quality of the print. While color remained out of reach to most weekend shooters, black-and-white processing and printing at home certainly was feasible by the 1930s. Equipment consisted of a few trays, a steel or plastic developing tank, and a piece of glass. You didn’t even need an enlarger, really, if you were willing to accept images the same size as the negatives. These were called contact prints.

Contact prints worked all right if your camera used 120, 620, or larger film. These produced contact images about 2¼ inches square. But beginning in the late 1960s the 35mm film that had grown to dominate photojournalism spilled into amateur photography. These horizontal-format negatives were pretty small, a little over an inch high. This produced tiny contact prints. Fine for photo editing. Not so fine for general viewing. A machine to project the negative image onto a piece of sensitized paper at a larger size was necessary. That was called an enlarger.

Ross with enlarger.Enlargers cost a bit, but certainly the basic models were within range of an amateur’s budget. But one problem remained: darkrooms had to be, after all, dark. That is, no light could leak in, from any crack, any window shade, anywhere, not even a sliver. Emulsion was so sensitive that even the tiniest speck of light would possibly fog the film. And while printing paper wasn’t quite as sensitive, still, the room had to be for all practical purposes pitch dark.

Bathrooms and basements.

One obvious solution: a family bathroom. Many amateurs set up equipment in the bathroom, draping a blanket over the door and windows. (Or did their work at night when sunlight won’t squeeze through even the thickest blanket.) This also was ideal because darkroom work requires a source of water. Voilà!

A problem, of course, was that people might want to use the bathroom. And the equipment probably had to be packed away between sessions.

Many enthusiasts opted for something more workable. The basement was the obvious answer. A fruit cellar was perfect: generally no windows and pitch dark by its nature. If that were not available, you could drape some blankets behind the furnace, or if you were really lucky, build a little room in a corner. Most laundry rooms had a sink, and most of them were in the basement.

My first darkroom, built when I was 13, was a space behind the furnace in my mother’s house. I nailed thick cardboard over a basement window.

Spotone.Because most amateurs relied on darkrooms squeezed into unfinished basements, these spaces were as expected fairly crusty. Chipped paint, stains on the walls, spider webs and mold: standard home darkroom décor. The one thing you couldn’t have was dust. Dust was the enemy of print-making, as it left white spots on your prints. Detail-driven photographers aiming for high-quality prints used an inky substance, usually Spotone, and a brush to carefully touch over these spots. You may imagine this skill took some time to acquire.

So did the skill behind effective work in a darkroom. Developing and printing pictures is a process requiring fine motor skill facility. That is, you have to refine your ability to do things by hand. As machines do so much of our work nowadays, most of us do not have the high level of skill needed for detailed hand work. We see this in other areas that have become more automated, such as woodworking.

Rolling your own.

We also see it in photography, as digital-based images have all but replaced traditional darkroom skills. You do indeed need skill to produce high-quality images using Photoshop software. But that skill is different from the practical hand-on skills required in the darkroom.

When I taught darkroom-based photography, the biggest challenge for most students was learning to develop the film. In total darkness you must open the film cassette, remove the film, tear or cut off the end, roll the film onto a reel, place the reel in the tank, and put the cover on. If you would like a lesson in the difficulties of working blind, this is a good start. Rolling the film is the hardest part—it isn’t even so easy to do with the light on. As both teacher and student over many years in university darkrooms I have heard all sorts of colorful language emanating from somewhere in the obscurity as students worked to learn film rolling.

The industry offered gadgets to make rolling easier. While they did help, it was considered the loser’s way out. Real photographers rolled their own. Film, that is.

But the fussiness of the darkroom doesn’t end with the film reel, or the dust you have to control. Developing film requires careful control of time and temperature. The standard temperature for black and white is 68 degrees F., or 20 degrees C. Why 68? At one point in the past it was considered optimal for quality negatives with as fine a grain as possible. Later that was not so true, but tradition is tradition. You need a darkroom thermometer capable of accuracy to one degree F. You can’t vary development temperature by even a degree without seeing an effect. As for development time, it depends on developer brand and sensitivity ("speed") of the film. It's usually 6 to 8 minutes. You must use a timer to accurately keep track.

You also need to carefully agitate the tank during the process—usually 5 seconds of gentle turning for each 30 seconds of development. Keep a careful watch on that clock! Because time and temperature control is absolutely critical to good negatives.

Both developing and printing require at least three chemical baths: developer, stop bath, and fixer. While chemical-based stop bath exists, most amateurs for about the last century have just used water. The developer washes away the silver compounds of the unexposed areas, while the fixer freezes the rest so they are no longer light-sensitive. After about five minutes in the fixer you can safely open the tank. Most photographers then dunk the reels into a hypo clearing solution to remove all traces of the fixer (also called "hypo"). Wash in running (temperature-controlled) water, dip in a wetting solution such as PhotoFlo to promote spot-free drying, and hang on the line holding only by the edges. In a dust-free place, of course. The damp emulsion will be soft, and easily scratched, so it's best to leave the film at least overnight before printing.

People sometimes wonder: what happens to all that extra silver in the developer solution? The answer is that, yes, we throw it away. Some high-volume labs used to recapture that silver, but for amateurs such a thing is hardly worth the time. And yes, we throw chemicals down the drain. Not into the storm sewer. They need to go through the city’s water treatment plant for safety.

If you are not going to print for a few days, cut film into strips of five and place in an envelope or special negative sleeve. If you leave negatives drying too long on a line, they’ll gather—what do you think?—dust. And you do not want to employ that annoying Spotone (which inevitably spilled to ruin your clothes) any more than you have to. If you can even buy it anymore; I think the company is out of business.

Printing the neg.

Safelight.The printing process is separate from developing, and uses a different developer. On the good side, you don’t need to print in total darkness. On the bad side, you do need to print in nearly total darkness. Because black-and-white printing paper is not sensitive to amber light, you can set up a faint light called a safelight so that you can (more or less) see what you’re doing.

First run a contact sheet so you know what you have. Gather all your negatives, place side by side on an 8 x 10 sheet of printing paper, lay a piece of glass atop, and expose it under the enlarger light. How long? Depends on density of negatives, strength (and age) of the enlarger bulb, and aperture of the enlarger lens. Yes, an enlarger lens has f-stops just like a camera lens.

Of course, printing paper isn’t as sensitive as film, so an exposure of a 5-15 seconds will be about right.

Printing is again a three-step process: one minute (at least) in the developer, a few seconds in the stop bath (water), and at least two minutes in the fixer. Most modern printing paper (resin-coated) needs only a five-minute running water wash. Hang on the line to avoid water spots as the print dries.

Question: Do those chemicals harm your fingers? Over the years I have known people who could not do darkroom work because they were allergic to the chemicals. And a legendary local photographer I met during my youngster photo years, Ham Gillespie, always had crusty fingers stained brown. Best practice not only to avoid touching the chemicals but also to avoid contaminating the developer with the fixer is to use two rubber-tipped darkroom tongs.

Making it bigger.

We choose pictures to enlarge based on our contact sheet using, probably, a magnifying glass or loupe. Each frame has a number next to it. Considering prints that look worthy, find the corresponding number on the film. Note: you will save yourself lots of irritation by being organized. Save each film in a separate envelope, and number that envelope corresponding to each contact sheet.

Try to avoid shifting the negatives in the envelope, as they can scratch each other, and handle mostly by the edges. Fingerprints transferred to a print are nearly impossible to remove using Spotone.

Wash your hands; clean hands will save many a fingerprint or cross-contamination annoyance. Use a clean brush or better yet compressed air to dust your chosen negative.

Slide your negative into the enlarger’s negative carrier. Turn off the overhead lights. From now on, it’s just you and your dim but friendly safelight. (And maybe a radio.)

Pull the enlarger head up or down to reach the size you want, and consider cropping. Focus carefully. Many photographers use a grain focuser for more precise work. This viewer enlarges the film grain in an eyepiece so you can focus perfectly.

Run a test print. You can do this the traditional way by choosing a whole (usually 8 x 10) sheet, and exposing it about 30 seconds at about f/11. Cover 80 percent of the sheet with a piece of cardboard. Each 10 seconds move the cardboard away to uncover about 20 percent more of the sheet. That way you can see several possible exposures and so determine the best.

Or if you want to do it the less wasteful way, as I do, cut one sheet into several strips. Place a strip under the enlarger, and expose as you guess might work best. Develop. Adjust based on what you see. You may have to do several test strips.

Sometimes—well, most of the time—areas of the image will be too dark or too light. An ideal black-and-white print retains detail in both the highlight and shadow areas. That is, no large area is completely black or totally white. To obtain this detail, you may need to hold back light from the parts that are too dark (called dodging) or add light to the areas that are too light (called burning in). A face in shadow often needs dodging; an overcast sky often needs burning.

Dodging is done using a (usually) hand-made tool consisting of a wire with a small piece of cardboard taped to the end. During part of the exposure, move the tool around the area to be dodged. The tool must be continually moved, or the wire will show up in the final print.

Burning in may be done with a cardboard into which a hole is cut, or simply with both hands held to add more light to the appropriate area. Again, keep moving.

Dodge and burn icons. Now you know what those odd-shaped icons depict in the Photoshop's “dodge” and “burn” tools.

Finicky photographers may enhance the intensity of the shadow areas (D-max) by using another chemical, typically selenium toner. After washing the print, leave in diluted toner as indicated in instructions. Selenium toning also guarantees an archive-stable print. It will last for a century, probably more. We have a century of experience evaluating the longevity of silver-based prints: those produced even 150 years ago still look good if they were not exposed to sustained intense light. The key to permanence is to carefully wash away all traces of fixer, as it is that chemical that spoils prints.

How long will digitally produced ink-jet prints last? We’re not sure. But 25 years is our best estimate. Digital files, too, may become corrupted with age. Yes, the old chemical process demands time and skill. But the reward is a print that rivals the unique quality of art media such as engravings, and a print that will stand the test of time.