Whats the “three year rule” of lens design?
It’s sort of like “Moore’s Law” for optics. Several years ago, a lens designer (still trying to remember the name) pointed out that, because of increased computing power and optics design software availability: “In the last three years, more lens design computations had been performed than in the entire, centuries long history of optic design before them” And that this will also be true of the next three years, and the three years after that. This is why we’re seeing zoom lenses that rival the performance of prime lenses from a decade before, and an explosion of versatile, high performance optics.
