Digital black & white photography

So you see how the picture will appear when it's recorded. When you take the picture the colour signal is still recorded by the CCD, but the image is desaturated when processed to remove all colour.

If the Sepia mode is used a colour shift is applied to create the red/brown hues. If you do not have a computer it's essential to switch to one of these modes if it's the kind of output you require. But computer owners can desaturate a colour image using even the most basic image editing software and its Hue and Saturation mode.

Sepia used here to create an old feel

Where shooting in black & white becomes more interesting is when filters are used. Then you can play around with how a particular colours appears in black & white. We covered this in an article last month here: Using filters for black & white photography. But briefly, a red filter, for example, placed over the lens when you take the photo will lighten any red colours in the image so they appear lighter shades of grey than blue or green colours.

So if black & white is something you enjoyed doing with a film camera you can more or less repeat the process using your digital camera. You'll need a filter holder so the filters can be attached or you can hold them over the lens while you take the shot. The viewfinder won't show you the change of tones, but once the image is taken you can preview on screen and see what's happened.

Digitally recreating filter effects Once again, the effect of any filter can be recreated electronically in a colour image by using the Channel mixer in Photoshop. It's one of the more advanced Photoshop options and with this you edit each of the red, green and blue channels that make up a colour image to lighten or darken each part of the spectrum and affect the brightness of each tone. Become familiar with this and you have the most versatile method of adjusting the tonal range of a black & white image.

More life like results Another characteristic of black & white is grain. Photographers often use different film/developer combinations to enhance or reduce grain. Digital photographs are grain free and often look "digital". Most image editing programs have a filter that adds grain (or Noise). And there's usually a slider to control how much is added. You can even play around and create infrared style results and almost emulate the hard grain achieved using Kodak High Speed Infrared film.   Monochromatic Noise was added to the picture below.

Printing black & white images
When you're happy with your black & white digital files you'll want to print them out and here you need to consider the printer's settings to ensure the pictures come out as you see them on screen. When an inkjet printer is left on automatic it will print using colour mode and convert the file to output as a CMYK (Cyan, Yellow, Magenta, Black) image and the four (or six) inks are combined to make the various shades. You may find using the normal settings that the prints produced will have a slight colour hue. Sometimes this is effective, but is often not required so a tweak in the software is required to make the tones neutral. You can also go into the properties option when you are about to print and select greyscale mode which will print using just the black cartridge, but this can often surpress tones and you end up with an average quality result. Another option if you have Photoshop is to convert the photograph from RGB to greyscale then back to a Duotone which gives you an image made up of two colours which can be adjusted to get very fine colour hues such as blue or sepia that print out wonderfully.

For the more advanced users who have certain Epson or Canon printers you could consider taking out the colour cartridges and replacing them with a set of black inks that produce accurate black & white images. These are made by companies such as Lyson and come in various forms offering neutral cool or warm tones.