In this post, I’ll cover the techniques that are the best to use to convert your images to black and white. They’re the most intuitive to use, and they also provide a lot of flexibility in your conversion. Included in the advantages of these techniques are that they are non-destructive – the Channel Mixer and Black and White adjustment are both available as adjustment layers, and the ACR black and white conversion can be done as a smart filter in Photoshop CC.
Technique 8 – Channel Mixer
This used to be one of the best ways to convert an image to black and white, and was the go-to option until Photoshop CS3 brought in the Black and White adjustment, way back in 2007. While this can be done by going to Image, then to Adjustments and choosing Channel Mixer, it is far better to do this as an adjustment layer.
Once you’ve selected the Channel Mixer from the list of adjustment layers (the half black, half white circle at the bottom of the Layers palette), make sure you tick the “monochrome” box. This will set the three sliders to 40% for red, 40% for green and 20% for blue as a default setting. Each slider will affect one of the three colour channels. Sliding to the right will brighten the particular channel, while sliding to the left will darken that channel. Underneath the sliders, you’ll see a total, which tells you the total of the three sliders. To keep the image properly exposed, try to keep the total at 100%. If it is under 100%, your image will be dark, and if it is above, your image will be too bright. You can also use the constant slider to make some alterations to brightness.
Another advantage of this technique is that it gives you presets, so you can just choose one of those and go for it. The presets for the red, yellow or orange filters often work quite nicely for portraits, but as always, play around with the settings.
Technique 9 – Black and White Adjustment Layer
First introduced in Photoshop CS3, this adjustment made it quick and easy to make black and white conversions. Like the Channel Mixer, this uses sliders, but instead of just the red, green and blue sliders, the black and white adjustment has red, yellow, green, cyan, blue and magenta, giving much finer control.
Again, this is best used as an adjustment layer, to prevent altering pixels permanently. Once you have the adjustment layer dialogue box open, it’s a simple matter of adjusting the sliders as you see fit. Sliding to the right will increase the brightness of a particular colour, and sliding to the left will darken that colour. It can sometimes be difficult to see the effect a slider has, particularly if there is not much of that colour in the image. I like to quickly slide between the far left and far right to help me easily see what parts of the image will be affected and then make my adjustment.
Another benefit of this is that you can use a targeted adjustment tool. If you click on the icon of the hand with the sideways arrows, you will be able to click and drag on the image, adjusting just those colours that you clicked on. This will let you adjust just the colours you want, giving you even finer control than using the individual sliders.
Technique 9 – Camera Raw HSL/Grayscale Panel
Starting in Photoshop CC, you are able to open Adobe Camera Raw (ACR) as a filter in Photoshop, making it very easy to use it to adjust jpeg images (you can get Photoshop CS6 to open a jpeg in Raw, but it’s rather convoluted, and I won’t go into it here).
Unlike the previous two techniques, this can’t be done as an adjustment layer, but we can do it as a smart filter so it won’t make any permanent changes to the pixels. On your background layer (or merged layer if you have already created several layers that you have worked on), right click and choose “Convert to smart object” from the pop up list. Now go to the Filter menu and choose “Camera Raw Filter.” Once the ACR filter comes up, click on the fourth icon over on the right-hand side. This is the HSL/Grayscale panel. If you are working in colour, this gives you the option to change the hue, saturation and luminance of each colour, but if you tick the “convert to grayscale” box, you’ll only get one (since hue and luminance won’t affect an image without colour). The sliders work the same way as the sliders in the Black and White adjustment described above, but there are even more; eight colours instead of six. Slide them to the right to increase the brightness of a colour and slide them to the left to darken a colour. And again, you can use the targeted adjustment tool to click and drag on the image to make your changes (this time it’s on the toolbar along the top).
The techniques I’ve covered in the last few posts are the most common ways to convert an image to black and white. As we’ve seen, some of them give a great deal of flexibility, while others are severely limited, and others, while useful, are far from the ideal choice for artistic monochrome conversions.
After converting to black and white, you may want to apply a tint to your image to make a duotone, a tritone or even more. There are several different ways to accomplish this, but I’ll cover them in a future series of posts.