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Apply a red, yellow or orange lens filter to sharpen the contrast of clouds. A color filter may make the clouds appear more bold or sharp. This lens increases hue saturation, and may work well with sunsets and red flowers. Tungsten lighting is produced by light bulbs, and cameras lose the array of blues. When using filters in photography, you may apply them to increase colors the camera does not record.

Summary:
Employ color filters to change the contrast in black and white photography. Apply a red enhancing photography filter to make brighter reds, browns and oranges. Put a blue filter on your lens for use with indoor tungsten lighting.