As an engine is the heart of a car, an enlarger is the heart of a darkroom. It is the instrument through which negatives are brought to life. Along with a good lens, it is the enlarger around which the rest of the darkroom is built. A darkroom can have the best plumbing, great stereo and stainless-steel trays, but without a good enlarger and lens, it can be difficult to produce quality images.
It pays to buy the biggest and best enlarger you can afford at the time. Sometimes it is beneficial to purchase an enlarger that will accommodate a negative larger than the format you currently shoot. That is, if you are now shooting with only 35mm, it might pay to invest in an enlarger (and lens) that will accommodate larger-format negatives, since at some point, you might decide to step up to a larger film format. The thought of having to buy a second enlarger because you’ve since bought a larger-format camera can be daunting and financially painful.
When installing the enlarger in your darkroom, it is recommended that you bolt it to a wall, table or floor to minimize shake and vibrations. Also, don’t forget to divide your work area into a “wet side” and “dry side,” with the enlarger on the dry side. There are many excellent books available which outline and diagram efficient darkroom design.
Other accessories to think about when buying an enlarger are: extra lamps, negative carriers, a good easel, a good timer, a good grain-focusing device, and, since dust is the biggest enemy of the darkroom, a good supply of compressed air—and a dust cover.
The principle of the enlarger is simple. It is a box with a light inside that transmits that light first through a set of glass condensers or an opaque white diffuser or through a white chamber from where it is bounced and reflected downward, on through the negative and then through a lens. The resulting reversed image is projected onto a sensitized piece of paper which, in turn, is placed in chemistry that develops the image. An interesting characteristic of enlargers is that they differ from cameras in one major aspect: Whereas a camera makes a black-and-white negative that reverses the tones of a scene and renders the dark areas of the scene as light areas on the negative (and conversely, light areas as dark), an enlarger reverses the process. Simply, the dark areas on the negative block more light and print as highlights, and the light areas allow more light to pass through the negative but print as dark tones.
Enlargers differ in several ways. Some are ostensibly for black-and-white negatives, some are for printing color. Some will only hold 35mm negatives, while others can accept larger negatives, up to 8 x 10". Please note that an enlarger that prints 4 x 5" can also print smaller negatives but an enlarger that only prints 35mm will not accommodate a larger negative. Enlargers can also differ in the size of prints they can produce. An enlarger with a short vertical column yields a small print, while an extended column permits the printing of larger images because you can move the negative and lens further from the easel that holds your printing paper. In addition, certain enlargers can reverse their columns, permitting you to place your easel on the floor for larger prints, while others can rotate their columns for wall projection. A rotating column is especially valuable when your darkroom space is limited.
There are also several types of enlargers that are categorized by the nature of the light sources in their heads, since they can generate different qualities or types of light.
The most common kind of black-and-white enlarger is the condenser enlarger. Light from this type of enlarger is “collimated;” i.e. the light is focused to a point in a “cone of light.” Condenser enlargers tend to produce very sharp, crisp prints because the kind of light they produce is specular, or coming from a single direction through glass lenses called condensers. Because the light is generated from an incandescent bulb, they also have a tendency to heat up and cause negatives to buckle if they’re left in the negative holder for too-long exposures. Since the light from condensers is specular, prints from these tend to show up dust and scratches more prominently than other types of enlargers.
Moreover, a portrait printed with a condenser enlarger will be less “forgiving” to imperfections and blemishes on the subject’s skin. Contrast control with this type of enlarger is generally achieved through the use of either graded printing paper or the combination of variable contrast paper and variable contrast filters (which are held either under the enlarging lens or above the negative, depending on the design of the enlarger). It is possible to print color images using a condenser enlarger; however, this requires the use of individual, separate color filters. This process can be time consuming and frustrating if the user is not familiar with color filter printing techniques.
Variable-contrast enlargers allow the user to adjust the contrast of the print within the enlarger itself, rather than having to maintain a supply of graded paper or external filters in a drawer or rack in the head or under the lens. These enlargers have built-in dials with contrast grades on them. By rotating a dial either up or down, the contrast of a particular print can be manipulated—in some instances without a change in exposure time. Variable-contrast enlargers use a special fluorescent bulb or tubes, diffused through a piece of opaque white plastic, opal glass or a Styrofoam box through which the light is passed or bounced. The resulting light is more diffused and less directional, i.e. softer, and can be more pleasing, especially for portraits. These enlargers also offer the benefits of split-contrast printing, with which you can deepen the blacks in a print while maintaining creamy-looking whites.
Color enlargers use dichroic heads containing dial-in filters of Cyan, Magenta and Yellow. By adjusting each of these filters to the appropriate setting (determined through test printing or by using a color analyzer), a proper print can be produced. It is also possible to print black-and-white images on a color enlarger. This requires more knowledge of C-M-Y filtration techniques. Some professional photographers and custom printers prefer this method because it yields a less harsh, contrasty image than a condenser enlarger. You can steplessly control the contrast of VC paper, which you can’t do with filters that are rated at an absolute contrast value.
You'll get as many arguments about which is the best enlarging lens as you will about who makes the best camera bag or which city has the best baseball team. The important thing to remember about enlarging lenses is that each film format requires a different basic focal length with which to print. For example, for a standard 35mm negative, a 50mm enlarging lens is normally recommended as the “normal” focal length. For a 6 x 7 negative, up to an 80mm lens is used, and for 4 x 5 negatives, up to a 150mm lens is recommended. There are times when a different lens might be used, but when you’re first getting started with printing, it is best to stick to the rule of thumb and experiment once you have more familiarity with the process. Quality of lenses varies from manufacturer to manufacturer and model to model. This is one of the oldest debates in photography. Ask ten printers for their favorites and you’ll get ten opinions on enlarging lenses. Today, the discussion usually comes down to two: Schneider and Rodenstock. There is still a used market for other well-known manufacturers, such as Nikon and Leitz. The truth is that they are all good. One may appear to be a touch sharper, while another may be less contrasty. It comes down to nuance, and depends on how you like your prints to look.