Join Tim Grey for an in-depth discussion in this video The value of color, part of Photoshop: Black and White (2010).
It might strike you as a bit odd that we're even focused on creating black and white images from a color original rather than just capturing in black and white from the start. After all in the days of film, you could choose between black and white or color film. As you'll see in this lesson, even if you have no interest at all in color photography, there is still tremendous value in using a color photo as the basis of a black and white image. A grayscale image contains only luminance information. Here we have a grayscale version of the image, and it looks reasonably good as a black and white, but there's not a lot of information here.
What that means, is that we're not going to have very much flexibility when it comes to interpreting this image, or optimizing it to make it looks its best. When we have a color image, there's actually three times more information, let's see what that looks like. If we go to the channels panel, we'll see that this grayscale image has only one channel. This is the only interpretation of the image when it comes to a black and white version. If I switch to my color version of this exact same photo, you can see right away that there's much more information. We have shades of green, of yellow, of blue and other colors throughout the image.
Each of those colors has their own luminance information. And so we can use that information to create a wider variety of creative interpretations of the image. Looking at the Channels panel, you can see that we have a red channel, a green channel, and a blue channel. Three channels, rather than the single channel for the grayscale image. And looking at each of these channels, you'll see that they each look different. They're each contributing something else to the image. Granted, certain areas of some of the channels may not look very good, but the point is that we have a lot more information to work with.
We can blend this information together in varying degrees and in different areas of the image in order to create an interesting and pleasing grayscale version of the image. In other words, even when our intent is to produce a grayscale image, we're gaining an advantage by starting with color information. Even when your sole focus is on creating a black and white image, starting with a color photo can help you achieve the very best results. As you've seen in this lesson, even when you only want to share a black and white version of the image it's still best to make full use of the RGB color mode.
- Understanding channels
- Using the Lab color mode
- Adding a black-and-white adjustment layer
- Adding a color tint
- Applying a Curves adjustment
- Using the Gradient Map adjustment
- Adding a vignette or film grain
- Dodging and burning
- Selective black-and-white