High contrast printing involves eliminating or subduing the middle tonal values, thus producing an image where the visual information is communicated in tones of pure black and white. High contrast can be used to make near line-drawing renditions, or to create highly graphic interpretations of a scene. As it mutes information in the middle values it accentuates the lines and forms that define the subject.
Virtually every image can be printed in high contrast; critical and aesthetic decisions, however, will limit this technique to certain moods or scenes. Fashion, urban landscapes, portraits, architecture and winter scenes are the most common types of images on which high-contrast techniques are applied, but this by no means limits the possibilities.
First we’ll discuss printing in the darkroom, then with computer processing. The simplest way to achieve a high contrast effect is to work with a high-contrast paper or high-contrast filter when using VC paper, namely a #5 grade. With most negatives, this choice eliminates many of the middle gray values.
Unlike more commonly used grades, such as #2 or #3, grade #5 has a rather narrow exposure latitude, which means that critical testing is key. Expose too long and the whites will "gray up"; underexposure may yield a very weak image. (#5 can also be used to correct very underexposed negatives, and will often reveal details not seen by the untrained eye.)
If even a #5 grade fails to yield the desired result, use of a "lith" film as an intermediary will do the trick. Lith (also called ortho) film is available in formats from 35mm up from specialty shops like B&H. This film is made for document and line drawing recording; when developed in a special high-contrast developer no middle gray values will record.
You can also make an inter-negative from an original negative or slide. To make it from a slide, all you need do is enlarge or contact print the slide onto the lith film, just as you would make a print. This will create a reversed, or negative image, which you can then use to make a positive print. To make a lith negative from a negative, first enlarge or contact the negative onto the lith film, and then enlarge or contact that positive onto another sheet of lith film, which will create a negative. (All photo imaging, when done on film or paper, goes negative-positive-negative-positive, and so forth. This allows for some interesting image derivations.) Lith film can be processed under red safelight conditions, so you can inspect the negative as it develops to get it just right.
Once the lith negative is created, you can retouch it with dye to eliminate any gray values that may still exist; when you opaque a negative that opaqued area will print white. After you're satisfied with the negative you can print on virtually any grade paper to obtain a high-contrast image, though a #5 will guarantee the best effect.
For those who want to work in the computer just take the image file and open up Levels or Curves and pinch in the sliders. This is like printing on a higher contrast paper. Another interesting effect is using the Threshold command (you can do this as an Adjustment or an Adjustment Layer) and use the slider to determine the look. This is pretty much a visual fix and is a very simple and fast way to do it.
High contrast does not always mean just black and white; there may be an alteration of tonal values to accentuate a "hard" contrast with some gray values remaining. This effect can be used effectively for all manner of imaging where you don't want a line-drawing effect yet want the graphic appeal of a higher-than-normal contrast image.
Photo and text copyright George Schaub 2010. This image was scanned from a high speed color slide film, then made hi-con via a Threshold New Adjustment Layer in Photoshop.
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