What is chromatic aberration?

2 Answers

This is a defect with ordinary lenses.White light contains 7 colors and ordinary lens can not focus all colors at same point.


Due to differences in Wave length the 7 colors focus at didfferent points.If you use this lens the stars will appear like rainbow colorenter image source here .
picture credit photographylife.com.

Jul 28, 2017

At an elementary level we often teach that the refraction of light is independent of frequency, but that is obviously false, otherwise prisms would not split white light into colours.


The answer above is entirely correct, I just wanted to point out where I think the misunderstanding comes from. It's a problem in all optical equipment, particularly telescopes.