Note: This post builds on information presented in the Luminosity Masks and Luminosity Painting tutorials located on my website. Some familiarity with the techniques in these articles will be necessary to understand the edge-burning process presented below.
Ansel Adams in his book, The Print (Book 3 of The New Ansel Adam Photography Series), offers this insight about edge-burning, a process for slightly darkening the edges of a print:
“Mounting or overmatting a print with white board has a tendency to produce a faint ‘flare’ effect around the border, where the image may appear slightly weak. This is a visual effect only. A slight burning of the edges of the image seems to ‘set’ it in the mount and helps to hold the eye within the format.” Adams then goes on to describe two methods for edge-burning in the darkroom.
While true darkrooms, like those in which Adams created his art, are increasingly uncommon, the concept of edge-burning is still sound. Judiciously darkening the edges of a print can not only alleviate the “faint flare effect” from white board mentioned by Adams, but it can also provide increased visual appeal regardless of where the print is presented. Edge-burning subtly keeps the viewer engaged with the image by preventing the their eyes from drifting out of the frame, and it’s effective with web-based images, framed pictures, and even loose prints.
Edge-burning should be distinguished from the common term, “vignette.” A vignette is usually more perceptible, as in lens vignetting, where there is obvious fall-off of light at the edge of the frame. Alternatively, a purposeful vignette may be added to an image to create overtly dark edges as a way to add style or emphasis. Vignettes can easily be corrected or added in Photoshop via the Lens Correction filter (Filter > Lens Correction). Most RAW converters also have a vignette functionality that provides users an easy method for dealing with vignetting issues.
While the automated vignettes in image-processing software can be useful for edge-burning, each image has its own distinct needs and will often require a more individualized approach. For example, some edges may need more burning than others and the amount of burning may also be variable along any given edge. Additionally, the “depth” of the burn into the frame may need to be adjusted depending on the elements in the picture and where they are located.
My preferred approach to edge-burning is to use luminosity painting through a selection of the image’s basic mid-tones. Luminosity painting allows me to place the edge burn exactly where I want it and to build it up to whatever degree is needed for a particular section of the image. The image below is one where edge-burning was helpful in creating the final tonal balance of the image. Rolling the mouse over the image will show what it looks like with the edge-burning removed. (It may take a moment for the second image to load, but once it does, you should be able to pass the mouse back and forth across the edge of the frame to flip the edge-burning on and off.)
When looking at this image initially (no rollover), the edge-burning is not obvious. It’s meant to blend into the image in an almost imperceptible manner. However, removing the edge-burning (rollover) makes a very noticeable difference. Once gone, the eyes are drawn more to the lighter edges of the frame, and the visual focus on the balanced rocks is lost to some degree. While the rocks are obviously the focal point in the image, edge-burning effectively creates a tonal congruence to help establish this fact. What the eye perceives is now reinforced by the tonal values in the image.
Below is the what the burn/dodge layer looked like after painting through the basic mid-tones mask to create the edge-burning for this image. As a reminder, this layer is 50% gray to start with and is set to Soft Light blending mode. Painting black on this layer darkens the underlying tones to create the edge burn. So the areas darker than 50% gray represent places where burning (darkening) occurred. As you can see, not all edges were treated the same. In some places no burning was required. In others it’s quite heavy, and in still others very light. The depth of the burning from the edge is also variable. The goal was to create an appropriate edge burn in response to what the image needed.
The question might logically be asked, why is it necessary to paint through the basic mid-tones selection for edge-burning? The short answer is: It works! I’ve tried painting through both Lights-series and Dark-series selections and no selection at all, but keep coming back to the basic mid-tones. The reason–painting through this selection has the desired and predictable effect regardless of whether the edge is light or dark. A more technical answer would be that by targeting just the mid-tones for edge-burning, the lightest values aren’t grayed down and the darkest values don’t lose texture. As such, overall image contrast isn’t significantly affected by painting through the basic mid-tones, so the image still retains the look it had before edge-burning. This is very important. Remember, the goal is to be subtle with this technique; the effect should not be obvious or look out of place.
From a workflow standpoint, I first create the burn/dodge layer. Then I create the basic mid-tones selection or load it from the corresponding mask I’ve made on the Channels palette/panel. I usually start edge-burning by using a soft brush and black paint set at 25% opacity. I adjust the opacity up or down depending on how much burning is required. If it goes too far (the burned area gets too dark), I change the brush color to white and lighten things up again. Some parts of the image may require several brush strokes in order to be properly darkened. Painting is an extremely versatile technique so there is a great deal of latitude built into the process. In the end, it will be entirely up to me to decide how the edge burn should look. Fortunately, even with heavy burning, the blending of the burn into the image will be perfect. Painting through a luminosity mask insures this.
Below is another image that was edge-burned through the basic mid-tones. Again the rollover is the image with the edge-burning removed.
This image is more abstract than the previous one and there is no obvious focal point. Still, the edge-burning enhances its viewability. While there is no noticeable vignette, the slightly darkened edges keep the eye in the frame to explore the shapes and textures. So even though this is an abstract image with a rather monochrome color palette, edge-burning makes it more coherent. The technique provides a better balance of light across the frame, and as such, it plays an important role in image’s final presentation.
The burn/dodge layer for this image’s edge-burn is shown below. Again, the amount and coverage of the edge burn is quite variable within the frame and is specific for this image. Luminosity painting is an ideal way to create this individualized effect for each image and to vary it depending on your personal preference.
“My experience indicates that nearly all photographs require some burning of the edges. The edge-burning must not be overdone, however; the viewer should not be conscious of it.”
This was Adams’ last statement with regard to edge-burning in his book, and I agree with it. Most images do look better with some edge-burning, but keeping it subtle is key to doing it successfully. The digital darkroom makes available a much more nuanced approach than could be accomplished by Adams’ in his darkroom, but the intent and effect are still the same. I think it’s a nice finishing touch to add to an image and hope you’ll give it a try.