What Is a Camera APO?
Apochromatic (APO) refers to a type of lens design, not a camera designation. APO lenses use special low-dispersion glass to minimize color aberrations (abnormalities). APO lenses focus on more than one color of the spectrum to decrease chromatic aberrations.
Other People Are Reading
-
Camera Lenses
-
Uncorrected lenses act like prisms. They split and disperse light into its various colors. The speed at which light passes through a lens depends on its color (red, green or blue).
Characteristics
-
The design of an APO lens allows it to bring three colors of the spectrum (red/green/blue) into focus at a single point within the lens' s construction. APO lenses require at least one of the glass elements to have low-dispersion characteristics.
-
Types
-
APO lenses come in many different focal-length ranges from various manufacturers. Sigma makes APO lenses in the 70-200mm, 200-500mm and additional ranges.
Considerations
-
When buying an APO lens consider the cost vs. quality. APO lenses typically cost more than non-APO lenses but offer a higher degree of image quality. Determine the most important factors when deciding.
Tip
-
Most APO lenses for 35mm-equivalent digital cameras come in longer than normal (35-50mm) focal lengths. APO lenses for large-format cameras come in wide, normal and long focal lengths.
-
