Do you also believe in perpetual motion? Lenses curve different colors of light different amounts. You add more elements to try and neutralize it, at least in the center. Each lens is ground imperfectly and the glass has flaws too. You keep adding them, usually 5 or 7 elements to the point where there are diminishing returns. It will never produce a better image than the bare lens.When the lens is attached to a FF sensor, it will have the best peak sharpness, lowest pixel density, no additional optics.
But compared to using a FF lens with a simple adapter on a crop sensor, a Speed Booster might be better, because it is not punching on the image.
Upvote
0