Schmidt-Cassegrain telescopes are a popular type of compound telescope that combine features of both Schmidt and Cassegrain designs. They use a spherical primary mirror and a corrector plate to reduce optical aberrations, allowing for clearer images. This design makes them compact and portable, making them ideal for amateur astronomers. These telescopes typically have a long focal length, which provides high magnification and is suitable for observing celestial objects like planets and galaxies. Their versatility allows for both visual observation and astrophotography, making them a favorite among stargazers and astrophotographers alike.