#lens correction

• Achromatism — The property of an optical system to transmit or reflect light without producing chromatic aberrations, allowing the formation of a sharp image without fringing. In a medical or biological context, the term refers to the total absence of colored pigments in a tissue or anatomical structure, or a visual anomaly where the subject perceives the world exclusively in shades of white, black, and gray.
• Anastigmatism — An ideal optical property or characteristic of a lens or mirror system being completely free from astigmatism; the absence of asymmetric focusing distortions, allowing oblique light rays passing through the system to converge into a single precise focal point. This structural phenomenon guarantees uniform sharpness and an exceptional flatness of the image across the entire surface of the projection plane, eliminating marginal blurring.
• Astrophotographic — Belonging to astrophotography, relating to astrophotography; referring to the techniques, equipment, or processes used for photographing celestial bodies and cosmic phenomena. This term also describes optical instruments (such as refractors or telescopes) specifically designed to project a flat and color-corrected image directly onto a digital camera sensor.