Why are high end lenses constant aperture? Isn't the max aperture a limitation of the long end due to the size of the lens entrance pupil? Couldn't these lenses have even bigger apertures at the wide end with no increase in size?
What I'm wondering is: what would the physical difference between a 70-200 f2.8 and a hypothetical 70-200 f2.0-2.8 be? Shouldn't those come out at the same physical size? Or say a 24-105 f4 vs a hypothetical 24-105 f2.8-4?
Perhaps someone in physics and lens design has a good answer.
What I'm wondering is: what would the physical difference between a 70-200 f2.8 and a hypothetical 70-200 f2.0-2.8 be? Shouldn't those come out at the same physical size? Or say a 24-105 f4 vs a hypothetical 24-105 f2.8-4?
Perhaps someone in physics and lens design has a good answer.
Last edited: