|Digital Black and White
Submitted by *halley on 7/1/2002 Simulate B&W Film
If you want to make a digital photograph appear to be created on black and white film, GIMP and Photoshop have a very simple "Desaturate" filter. Some digital cameras have an identical function built into their software. It's adequate to take out the colors, but it's not adequate to simulate the black and white film process.
Here is one good method for getting better digital black and white "film" imagery out of your digital camera.
In Photoshop or GIMP, select the Channels tab on the layers/channels window. Then you can select and edit each color channel separately.
Select the RED channel. Turn off the "eyes" on the other channels and select only the red channel. Darken the whole frame a bit using the Brightness/Contrast tool or filter. (Black and White papers are notoriously undersensitive to red light; this conveniently happens to allow the use of red safelights in b&w darkrooms without screwing up the paper as much.)
Select the GREEN channel. Add some contrast to the whole frame a little bit. Adding contrast makes the bright green parts greener and the dark areas darker. (Black and white photographs typically have stronger contrast overall than color digicams produce. Developing by eye in a darkroom exaggerates contrast as well.)
Select the BLUE channel. Add some small amount of noise with the Noisify filter (in the blue channel only) then blur the whole frame slightly with the Gaussian Blur filter. (This emulates the overall graininess of typical hobby-grade black and white film.)
Now you can click the Layers tab and select the image layer to allow editing of all three color channels together as usual.
The image will look very oddly colored with the weak reds and the strong greens. Desaturate the image now.
Optionally, adjust brightness, contrast and sharpness of the overall image to taste.
Voila. A reasonable rendition of B&W film behavior all done digitally. Not perfect, but far more effective than the Desaturate tool alone, at emulating film.