Achromatic colors

By Dirk Metzmacher

Black & white images have their own special appeal that manifests itself in seriousness and objectivity. These are reasons which make the achromatic variant often preferred in nude photography. Photoshop offers numerous ways to achieve the same goal, but the results differ greatly in terms of quality.

From the color version to black & white

If you want to create a black & white image from a color photo, a simple click on Image > Adjustments > Desaturate is enough. But this function makes the result very flat, expressionless and low contrast. There’s a reason for that, of course. Different colors with about the same brightness are very similar as shades of gray.

Original photo: Gerti G.

Reduce saturation

So turning a photo into black & white at the push of a button results in an image with very little depth and dimensionality. These three color blocks show very clearly which effect this can have on the image as a whole. The color ranges that were clear-cut before are unrecognizable now. What remains is a long, gray bar.

The Channel Mixer

Up until Photoshop CS2 the Channel Mixer was the ideal tool to create „crisp“ black & white images. You’ll find it in the menu under Image > Adjustments. After checking „Monochrome“ to the lower left, you can increase or decrease every channel individually. A typical approach would be to decrease the „Red“ channel to about 70%, then increase the „Blue“ and „Green“ channels in an amount that results in an overall 100%. That isn’t necessary, but it makes for a more balanced image.

High contrast result

Using the channel mixer as opposed to a simple „Desaturate“ gives us far more contrast in a photo, which you can clearly see in the color bars in the example. The new mixture of source channels emphasizes each individual area better.

Black & white conversion

Photoshop CS3 offers a new tool to convert color photos to black & white images, and it can be used as an adjustment layer with all their benefits. You can choose one of numerous integrated black & white presets from the „Preset“ dropdown, or create your own and save it for later use. Image contrast can be adjusted very intuitively directly in the image instead of only using sliders.

Being forced to click Image > Adjustments > Hue/Saturation and activate „Colorize“ before to leave a bit of color to an image, you can now take this step right in the black & white options window by checking off „Tint“ and adjusting the Hue and Saturation sliders according to taste.

Gradient Map

A gradient map, which can also be found under Image > Adjustments, lays the colors of a gradient over an image and assigns them to the shadows and highlights, with the increments in-between forming the middle values. Numerous effects such as the background of a flyer can be achieved this way. Here I want to show a technique to quickly create a neat black & white photo.

I selected a gradient from foreground to background color, with the colors set to black and white, respectively. This is easily done with the keyboard shortcut „D“ that sets the foreground and background colors to their standard values. Now a click on Image > Adjustments > Gradient Overlay and confirming with „OK“ is all it needs to get a good black & white image. By the way, you can add a little noise with „Dither“ to smooth the gradient and minimize any unwanted banding.

Original photo: mmuens

Further alternatives

You could also dismiss all colors with Image > Mode > Grayscale or by deleting two of the three channels in RGB mode. Like so often, Photoshop offers numerous options to achieve the same goal. If you want to impose a very unobtrusive color mood on a black & white photo, you can use Image > Adjustments > Hue/Saturation. First reduce the Saturation to about 90, increase the Lab brightness 5 points and finally set the Hue to about 180.

This makes the image seem like a black & white shot, but the mood can be further adjusted by setting the first slider according to taste and giving the image a hint of color.

Original photo: tora

Black & white photos can also be upgraded through high contrast and a little grain. So here’s a tip to conclude this article: Pull up Curves, set a point smack in the
middle and set another one to form a slight S curve. Grain can be added by using Filter > Noise > Add Noise, using an Amount of 1 to 2%.