Are Zooms Always Sharper at One Extreme or the Other?

There is a statement often repeated about zoom lenses, which I have assumed to be generally true, or at least historically true. “All zooms are sharper at one end than the other.” I also hear a lot of people saying they bought Zoom A because it’s sharper than Zoom B. Is that sharper everywhere? Just … Continue reading Are Zooms Always Sharper at One Extreme or the Other?