Converting to Black and White
If you shoot on film, rather than digitally, you have the option of taking black and white photos with dedicated black and white film. Film camera bodies are much cheaper than their digital equivalents, so for the price of a good digital body you could get two film camera bodies and use one for color photos and the other for black and white.
But if you shoot digitally (like myself now) then your camera will only record images in color. You may have a camera that can record in black and white, but the in-camera methods simply convert the color image into a grey-scale file. Using an image manipulation package such as Photoshop gives you much greater control over the conversion process, so you are better off shooting in color and post-processing your images.
Converting color images to black and white isn't just limited to digitally taken photos. If you have your negatives or slides scanned, the techniques below can also be used to convert them to black and white.
If your camera or scanner can record black and white images, you should know that such images lose their separate red, green and blue values (different proportions of which make up each pixel in your image). So any valuable information that can help produce a better black and white photo gets thrown away using this method.
The key objective when converting an image from color to black and white is to keep as much tonal detail as possible, especially in the highlights (bright parts of the image). As with many things, there are quick and easy techniques with little control or more precise techniques with greater control where you can fine-tune the results and retain the ability to adjust them even further at a later stage.
Ok, enough waffle and onto the techniques. I use Photoshop so these techniques apply to that package. Each method starts with the Menu options you need to select to get to the required function. They should also work in Photoshop Elements although some of the menus (and how you get to some functions) will be a little different. Other manipulation packages will provide similar functions. Here's the original color image I applied the different black and white conversions to:
Lazy Method 1: Converting to Gresycale
Image>Mode>Greyscale strips the color information from each pixel in your image and leaves each pixel as a shade of grey running in range from black to white. There are only 256 grey-scale values that a pixel can have whereas a color pixel can have 16,777,216. So you can see how much information is being lost.
While this method is quick and easy and can work well enough, there is no control or flexibility and the entire image is changed forever - so make sure you back up your original image before you use this conversion method.
Tones can be muted but it's still possible to use some of Photoshop's other tools to improve things. Image>Adjustments>Levels for example is quick and easy to use once you've got to grips with histograms. Again, this is a destructive editing technique that permanently changes the image, so its best suited to quick jobs.
Lazy Method 2: Desaturating the Image
Image>Adjustments>Desaturate tells Photoshop to turn the image monochrome by setting equal red, green and blue values for each pixel. The only advantage of this method is that you can avoid destroying the original image.
Select Layer>Duplicate Image first and desaturate the copy. Or click on the New Adjustment Layer icon, select Hue/Saturation and then drag the Saturation slider to -100.
As with Greyscale mode, you have no control, and you have a larger file with the redundant color information.
More conversion methods to come, but you can see the results of the various methods at: Black & White Conversion Examples. This page has larger pictures, so it might be a little slow to load.
Black & White Photography Videos:
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