There are many ways to skin a cat in Photoshop and converting to mono is no exception. Here are some other popular ways to convert to black and white
Photoshop’s ultimate mono conversion tool is the Black & White tool, which offers an intuitive, flexible way to convert to black and white.
However, messing about with the Black & White tool’s color channels without restraint can lead to serious image quality issues such as haloes, blocking and noise.
There are many ways to skin a cat in Photoshop and converting to mono is no exception. Here we’ve compile 8 of the most popular alternative ways to convert to black and white.
For more on black and white photography, check out our in-depth guide Black and White Photography: what you need to know for perfect mono pictures.
Simply changing the Mode of your image from Colour to Greyscale actually offers a pretty reasonable mono conversion. Click Image> Mode>Greyscale, then click OK when asked if you want to ‘Discard colour information’. The problem is that you have zero control over the result. Switching to Greyscale also blocks many Adjustments and Filters, and you need to choose Image>Mode>RGB Colour to free them up again. If you’re really pressed for time this might be just the job, though.
+ Reasonable results almost instantly
- No control over result
2. Lab Color
Another quick and easy conversion technique. Again there’s no control, but it does generate a particularly light, airy and smooth looking result that’s well suited to delicate subjects and/or high-key or low-contrast treatments. Click Image>Mode>Lab Colour. Now click Window>Channels and click on the Lightness channel. To finish, choose Image>Mode>Greyscale and click OK.
+ Creates smooth, airy results quickly
- No control over result
Clicking Image>Adjustments>Desaturate is even quicker than converting to Greyscale, but the result is just slightly rougher and again you have zero control. Desaturation via Layer>New Adjustment Layer>Hue/Saturation, however, provides much more control and more pleasing results. First drag the Saturation slider to -100, then use the drop-down Edit menu to selectively vary the Lightness of the Reds, Yellows, Greens, Cyans, Blues and Magentas to taste.
+ Lightness control over individual channels
- Limited control compared with RAW
Calculations (Image>Calculations) enables you blend two source channels to create a mono conversion. By default, the channels are set to Red and the Blending Mode to Multiply. It’s worth experimenting with different combinations, but for non-portrait shots, this set-up plus a reduction in Blending Mode Opacity will usually produce the best results.
+ A quick way to create dramatic results
- Limited number of conversion settings
5. Channel Mixer
The Channel Mixer is a formidable device, allowing precise blending of the Red, Green and Blue channels to create a wide variety of mono effects. Choose Layer>New Adjustment Layer>Channel Mixer. Check the Monochrome box and vary the Source channels, ideally keeping the overall percentage total to around 100.
+ Great control and good results
- Requires time and experimentation
6. Gradient Map
For harder, high-contrast results, try the Gradient Map. Click Layer>New Adjustment Layer>Gradient Map and click OK. Set your Foreground Colour in the Tools Palette to Black, choose the Foreground to Background gradient and click OK. Refine the contrast by dragging the Colour Stop and Smoothness sliders.
+ Punchy results and fine-tuning available
- Best for mid to high contrast subjects only
7. Adobe Camera Raw: HSL/Greyscale
The Camera Raw HSL/Greyscale tab offers an effective method for converting RAW image to mono. Once you’ve primed your shot using the standard Camera Raw controls, click the HSL/Greyscale tab and choose Convert to Greyscale. You can then separate and enhance the individual tones using the eight Greyscale Mix colour controls. Further refinements are then possible within Photoshop.
+ Offers vast array of controls and effects
- Changes must be applied to entire image
You can re-create in Photoshop virtually all of the effects offered by third-party plug-ins such as ‘Black & White Studio’ and ‘Film Grain’ by Power Retouche. For example, you could track down grainy traditional 35mm films, scan them in and turn them into mono grain filters. For those without the time or inclination to do this, dedicated plug-ins can be used.
+ Extensive new controls and effects
- Quality plug-ins don’t come cheap
Making sense of RGB and greyscale
The colour in digital images is created by combining three different colour channels: red, green and blue (RGB).
Each of these channels can record just 256 shades of that colour, but when these channels are combined they can record more than 16 million possible colour combinations (256x256x256).
A greyscale image, meanwhile, is a black-and-white conversion made up of just 256 shades of grey, ranging from pure black to pure white.