A good companion to this article is the one by Lensrentals where they actually show what happens when the lens is stopped down, particularly the effect on flare

A good companion to this article is the one by Lensrentals where they actually show what happens when the lens is stopped down, particularly the effect on flare. https://www.lensrentals.com/blog/2008/10/front-element-scratches/ https://www.lensrentals.com/blog/2008/10/front-element-scrat...