what do nd filters do

ND (Neutral Density) filters are camera accessories that reduce the amount of light entering the lens without affecting the color. They are often compared to sunglasses for cameras, as they allow photographers to use a wider aperture or a slower shutter speed in bright conditions, or to create a specific motion blur effect. ND filters come in different densities, such as ND2, ND4, ND8, etc., and can be fixed or variable. Fixed ND filters have a set density, while variable ND filters allow the photographer to adjust the density by rotating the filter. They are commonly used in landscape, portrait, and long exposure photography to achieve creative effects and control exposure. Some photographers consider them essential, especially in bright outdoor settings, while others prefer alternative techniques like post-processing. ND filters are available from various brands and are compatible with different lenses, often requiring adapter rings for different lens sizes