What Are Flat Field Eyepieces?

Focusing lens

Flat field eyepieces are designed to assist telescopes, primarily fast telescopes with focal ratios around f/4 or f/5, correct the curvature of the image that would be seen. In essence they make the visuals flatter and more pleasing for the user. That’s just the basic intended reason for flat field eyepieces. Of course I will … Read more