To enhance image quality in telescopes, what is often corrected for?

Aberration refers to the various optical imperfections in a lens or mirror that prevent light from focusing properly, leading to blurred or distorted images. In telescopes, different types of aberrations can occur, such as spherical aberration, chromatic aberration, and coma. Correcting aberrations is crucial for improving the sharpness and clarity of the images captured through telescopes, allowing for better observation of celestial objects.

For example, spherical aberration results when light rays passing through different parts of a spherical lens converge at different points. This causes a blur, which, when corrected, significantly enhances the overall image quality. Telescopes often utilize special lens designs or multiple lens combinations to counteract these aberrations, making the choice to focus on aberration correction highly relevant in the context of improving telescope performance.