Black & White Photography Filters
Filters are often used in black and white photography as black and white are actually produced as tones of gray. Filters are used to make the gray tones look like the original scene.
The sky and clouds often blend together in black and white photos as white, so filters are used to separate the two. A red filter can darken blue objects more than white objects. So if you use this filter the sky will look black in the photo and the clouds will still be white.
Filters can also lighten or darken a color to make it seem to disappear or to stand out in sharp contrast. There are basically four filters for black and white photography. They are orange, red, yellow and green. Colored filters affect the prominence of different colored objects.
Filters for black and white photography generally range in price from about $7 to $270. They come in various sizes.