Manual exposure

From Nikonians Wiki - FAQs, Photo Glossary, Good Photo Locations, Help

Manual exposure is the M setting on Nikon cameras, where the photographer sets the aperture and the shutter speed separately. Most Nikon cameras give the photographer access to the light meter as an aid to doing this. However, best results are obtained for digital photography when the photographer takes a test image and checks the histogram, which gives information not only about average lighting, as provided by the meter, but also about the brightest and darkest values.