Color continuity. What it is and how to get it.
By Sara Frances, M.Photog.CR
All too often I am consulted to help repair an existing wedding album or portrait series where the color does not match picture to picture. The distraught client is usually too angry or too embarrassed to go back to the original photographer, not even to get a rebate on the bill. Image content may be good, but a storyline visually disrupted by lack of color continuity will leave most clients with buyers remorse, an unhappy state that lowers public confidence in our profession as a whole. Who's to blame? The photographer or the photo lab? The client only knows her investment in photography does not live up to her expectations.
In the psychology of color, continuity (color matching print to print) is all about perception. The mind supersedes the eye in the three-dimensional real world by interpreting colors by memory or by simply becoming used to variations caused by different lighting sources and intensities. We don’t give a moment’s concern, for instance, to faces that look dark and green at a summer picnic under heavy cover of tree leaves.
When viewing two-dimensional prints, however, both eye and mind are uncomfortable with colors that don’t match in comparison or have tonal bias contrary to how we think a particular scene or object should look. Think of the green faced interpretive portraits by Matisse and Van Gogh that caused an outcry in their time. We know intellectually and from experience that faces and fabrics photographed in bright sunlight will look substantially different when shaded by a green tree or in tungsten room light. Nevertheless we prefer a more neutral tone overall for realistic reproduction, and an almost unreasonably close color match when images taken in different situations are shown side by side.
This candid portrait (left) combines some of the toughest elements for a lab to correct: high contrast, delicate white detail, and inaccurate skin tone due to mixed lighting and auto white balance. The corrected image (right) shows an excellent marriage of softer contrast, a more pleasing skin tone, and detail preservation in the fine lace of the designer gown. Images ©Sara Frances
Of course we all have “memory colors” such as grass, sky and family skin tones. You can be sure every bride has a definite memory of the color of her gown; it has been my experience she will often overlook variations in her own skin tone if the dress looks perfect.
Four causes are responsible for most color match problems. The simplest is less-sophisticated lab equipment and/or lack of control over that equipment and its chemistry. Mistakes with color space, resolution, file size and poor Photoshop skills all threaten mismatched color output. Unwise editorial decisions are a flaw often overlooked by labs and photographers alike. Prints that will be displayed together or bound in an album must be laid out together for a final visual comparison before they are accepted.
The most egregious failing, however, is imprecise exposure and white balance in camera.
Labs have very little margin to recover from poor photographic skills. In the digital world, the responsibility for color continuity now rests largely in the photographer’s domain and in her instructions to and interaction with her lab.
The ideal photographer-lab relationship should reflect a symbiosis. It’s just as important to listen attentively as it is to make requests and ask questions precisely. If you’re like most photographers, you want the advantages of a professional photo lab. Superior software and products, backed up by educational outreach and attentive customer service allow fine labs to don the cloak of the miracle worker, outputting a new level of color quality, with speed and price that rival grocery and drugstore mini-labs.
Education and communication are key. In a recent reader survey by Studio Photography magazine, about 65 percent of responding photographers said they are eager to “stay current with technology” and “sharpen their competitive edge” by attending seminars and other training events (Studio Photography, June 2007). However, photo labs report that basic digital skills are not yet the norm. Debbie and Dave Digital, whether neophytes or experienced photographers converted to digital, must take a great deal more responsibility with exposure settings and file preparation in order to get optimal output from their labs.
Arnie Burton, Customer Service Director at Miller’s Professional Imaging, relates that 75 percent of the wedding and event photography they receive is still captured using auto white balance.
Careful white balance setting in both RAW and JPEG is the one major secret to better quality prints. It’s a benchmark you must meet on the way to optimizing color print quality and matching from any lab. McKenna Pro spokesperson Michelle Power repeats it like a mantra, “White balance, white balance, white balance! Custom white balance should be your choice for 90 percent of photo sessions. This way skin will not carry the green or blue cast so indicative of auto white balance. The other 10 percent of the time, try out the white balance settings on your camera. In other words, find out what your camera can do for you.”
Shot within seconds of each other using ceiling bounce flash with auto white balance, the three images above exhibit typical color continuity problems that labs have a hard time correcting. The first and third images have yellow-green and magenta-blue color bias, respectively, due to the camera's interpretation in auto white balance. The second image showing flash misfire, is punchy, noisy and a different color altogether. It could be said that these are subtle differences "within tolerance" or that the color is "good enough," yet placed side by side in an album presentation, the color difference will be striking. Images ©Sara Frances
So why doesn’t auto white balance work well, since it sounds like the logical choice to handle the challenging variety of lighting and conditions at events? Simply this: The camera takes a fresh lighting measurement for every frame in auto mode, so color and density is slightly different in each and every capture.
Imagine what this means, for instance, if you use bounce strobe in rooms with different ceiling heights and walls painted different colors. Wavelengths of incandescent light, candles or colored mood lighting prevalent at every social event cause particular problems. In the warm yellow end of the spectrum, a substantial downwards shift in effective exposure will occur when color tones are neutralized by the auto white balance.
If you think you can fix it all later, you're adding a lot of work to your schedule. File correction software is much more effective when the color tone has been defined by means of the correct white balance, thus promising closer matching right from the start.
Burton recounts how attempts at color correction in the computer by well-meaning but less adept photographers can actually make the lab’s color matching job much harder. Many of my own university students come to class to gain color correcting skills because they’ve experienced the frustration of poor prints even after working hard to optimize an image. It’s better to give the lab an uncorrected image than one that has been tweaked multiple times in the wrong direction.
Read your camera manual to learn how to obtain a custom white balance and make the practice part of your working routine every time the environment or lighting conditions change.
Todd Jerred, President of Apollo Photo Imagizing, names overexposure—blown out image elements so severe that they cannot be recovered—as the overwhelming problem he faces, as detrimental as incorrect white balance to the ultimate satisfaction of the end client. Jerred adds that blank or unreadable CDs, file naming with non-permitted characters, incorrect resolution, aggressive compression, tiny file size and wrong color space all complicate lab workflow and create delays, not to mention compromised quality.
Insider information tells me that consumer labs haven an 80-percent color accuracy goal. This sounds good until you realize that it means one in five of your images will probably print poorly. And 80 percent is the goal, not always the result. The one-product simplicity and next door convenience of consumer labs has been useful to me from time to time, but I have also seen how their capabilities can easily fail to meet the color matching expectations of the professional photographer. With the volume of newcomer competition in our industry, quality of the final output can easily be a distinguishing mark that brings monetary reward.
Professional labs help us all out with their mission of digital education and communication with photographers. So long as the photographers work to perfect the new skills that digital exposure and file handling require, every lab I’ve talked to is eager to help shoulder the burden of meeting and exceeding client expectations.
Professional photo labs quoted in this article:
Apollo Photo Imagizing
Miller’s Professional Imaging
Sara Frances is an author of photographic books, a magazine contributor and adjunct professor of digital imaging at Red Rocks Community College. Her specialty is never duplicated digital composite albums filled with her personal brand of “pixel surgery” shown at her photographic atelier, Photo Mirage Imaging in Denver, Colorado. Contact her at email@example.com.