Which is better achromatic or apochromatic?
Slow achromats are poor for imaging due to their physical size and focal length, while fast ones put up intolerable chromatic aberration. Controlling chromatic aberration is an uphill battle that refractor optical designs face, and almost any apochromat is going to be better than an achromat for imaging use.
Slow achromats are poor for imaging due to their physical size and focal length, while fast ones put up intolerable chromatic aberration. Controlling chromatic aberration is an uphill battle that refractor optical designs face, and almost any apochromat is going to be better than an achromat for imaging use.
