Tuesday, June 24, 2008
Pro Tips: Going Gray
A good/better/best look at converting color photos to great black-and-white images
Remember when “black-and-white or color?” was a choice made before you took a picture? The awesome ability to convert a color image to black-and-white after shooting is only part of the story; the real trick is to do it well and to create black-and-white photographs that look every bit as beautiful as the old darkroom methods.
There's a black-and-white conversion method for every day of the week, and each has its own particular place. Any number could be called “the best,” depending on your own personal workflow and your preference for ease versus control. Too much control isn't a good thing if you're unsure of what you're doing, and when speed is a factor, simplicity may have value over control. The real key to great black-and-white conversions is to experiment, learn how to use different methods to the best of your abilities and know when to apply them. Here are three ways to go grayscale, listed in order from easiest to most challenging, least control to most.
Good: Grayscale Mode Change
The first way we all learned to turn a color photo to black-and-white is the one-click, convert-to-grayscale option in Photoshop's Image > Mode menu—and it still has its place. The trade-off for such simplicity comes in the form of a lack of control in what tones are assigned to what colors. In some cases, it's no big deal, but in other instances, the grayscale mode changes results in flat or muddy black-and-white images. Sometimes, though, as with the “autocorrect” functions for contrast and colors, the grayscale change is spot-on. In those cases, count your blessings and run with it. Why not take a stab at the one-click method every time—after all, if it works it works, and nobody has to know how easy it is.
The Darkroom Equivalent: A work print. Correctly exposed and processed, but lacking the drama of a great custom print.
When To Use It: If speed and simplicity are your primary concerns.
The Bottom Line: It works as well as you'd expect from a one-click step.
Better: Channel Mixer
After the Wow! factor wears off, newly digital photographers start saying things like, “That's neat, but now I want quality and control.” In terms of digitally converting color to black-and-white, the next logical step—and probably the most popular custom conversion option—is utilizing Photoshop's Channel Mixer. The Channel Mixer is a great method for blending the different channels in a color photo to achieve the same sort of effects as using color filters when working with black-and-white film.
Open the Channel Mixer under Image > Adjustments and spend a minute experimenting with the monochrome mixes. As you isolate individual channels, you'll see how a digital camera records a scene, with different types of information on each channel. Any single channel may be used as the sole source of the grayscale conversion, but with the channel mixer sliders, you also can adjust the influence of each channel on the finished black-and-white image. The nice thing about the Channel Mixer is that there's no “right” answer; it's all a question of personal taste. At least with Channel Mixer, those choices are in the hands of the photographer.
The Darkroom Equivalent: Paper grade and processing have the contrast and the tonalities right where they should be.
When To Use It: If you want great results, but don't want it to take all day.
The Bottom Line: It looks like you know how to make a nice print.
Best: Mixing Channels Locally With Layer Masking
By taking the already great approach of the Channel Mixer and combining it with powerful layer masking, photographers can make black-and-white digital images with all of the tonal control and nuance of a skilled darkroom printer. Turning a digital file's RGB channels into layers, photographers achieve the same effect as the Channel Mixer, but with the added control of localized dodging and burning to selectively adjust the influence of each channel on specific areas of the frame.
Simply cut and paste the individual RGB channels into their own layers and then adjust both the overall layer opacity as well as the opacity of portions of the layer through selective masking. This provides the utmost control over the tones in every part of the image. Individual shadows and highlights can be adjusted independently throughout the image, without having to rely on a wholesale conversion of the entire shot. It's a great way to get all the control of darkroom dodging and burning, along with the nondestructive (and always reversible) control of layer masking.
The Darkroom Equivalent: A Zone System print that showcases complete tonal control.
When To Use It: When you'll settle for nothing but perfection.
The Bottom Line: You're a black-and-white master in the digital age.