With the ease that comes with various sliders to control exposure and saturation, almost every photograph that goes through processing comes out making full use of the available range. Histograms are spread all across the values and the Curves tool users now make sure to use each and every value that can be employed for displaying the pictures. The pictures look good, full-bodied, rich in tones and colors but they sometimes lack the emotional impact. The art of creating low and high key images is getting lost.
Let us first understand what these low key and high key images are and how these are different from underexposed or overexposed images. Low key images are predominantly dark. The light is used in a way that only the key aspects of the subject are emphasized. High key images are the opposite of low key images. These are made of up of bright tones.
Low Key Photographs
Low key images invoke a variety of emotions. They bring our mystery, drama, contrast of feelings and exaggerate the main subject’s message. Painters have used this method from the time paintings became an art form till late into the Renaissance era. The famous Rembrandt painting of ‘St Peter in Prison’ is worth studying and so is his Self-Portrait.The low key photographs are high in contrast but if you look at the histograms, they are concentrated in the lower value regions (left sided).
(A photograph with predominantly dark shades. It adds drama to the image and draws attention to the area lighted by lamp. Notice the use of negative space as well.
Nikon Df with 50mm lens, f/5.6, 1/50 sec.)
The trick of the trade is to emphasize the shadows and work with them. Use them as negative space while empowering the main subject (Negative Space). Shadows become an important element in these compositions. These intense shadows also provide a three dimensional look.
Low key photographs are not underexposed photos but these are the photos where dark shades are present all over. Metering can be a challenge while creating these low key images and the ideal option is to use spot-metering mode. With the preview screen’s presence, a quick check of histogram is also useful. The exposure should be such that there is some texture and information available in the dark areas too. They should not be characterless black, but have different dark shades. When in doubt, go with the regular exposure or even over exposure (ETTR, or expose to the right of the histogram) and then bring the exposure down in post-processing.
Night photography, under moonlight and streetlights are great places to experiment. The purpose is not to capture the whole scene in front of the camera but to capture the main subject with various shades of darkness adding emotions to the final photograph. For indoor photography dark backdrops, focused light sources which create long shadows and simple subjects can be used. The enhanced contrast and predominantly dark tones tend to create strong emotional reactions in our minds.
High Key Photographs
These are the opposite of the low key photographs, as you might have already guessed. High key photography uses unnaturally bright and diffused lighting to blow out most or all harsh shadows in an image.
(A high key image of a baby. The pastel shades give an impression of innocence and purity. Nikon D200 with Nikkor 50mm, f/5 with 1/25 sec, off camera flash used. Post-processed in Gimp)
High key images usually convey a positive feeling or a jolly atmosphere. These photographs can also convey feelings of happiness, simplicity and even innocence. Sometimes depending on the subject, high-key images also give an impression of high standards and quality. No wonder that most of the apartments, hospitals and office-space pictures in magazine advertisements are all high-key.
Painters have used this technique for decades to emphasize the happiness in their works. Most of the pastels use this. Raphael’s famous fresco, ‘School of Athens’ also tilts towards high-key, and tries to work on emotions related with knowledge and touch the viewer’s philosophical aspect.
Some good starting ideas for experimenting with high key images can be portraits in bright daylight with light backgrounds. Children look very good when photographed in high-key due to the emphasis on their innocence and happiness. Harsh shadows have to eliminated as far as possible. This can entail use of reflectors or multiple soft light sources. Some amount of over-exposure also helps. Be careful when attempting over-exposure, the image should not loose all the information from the bright areas. The main subject should be bright but not washed out. High key images frequently have very low contrast. Trying to increase this in post-processing spoils the impact of high-key imaging.
With proper use of this technique, the impact of image can be increased many fold. It is not necessary that every photograph should have tonal values ranging from the lightest (white) to the darkest (black) possible. Limiting the tonal values to upper or lower regions can be very impactful. Use this along with the color theory to get the best results. (Using colors effectively)
Further Reading:
Using Partial Dynamic Range