There are a number of “do-it-all” zooms for full-frame and 35mm cameras, and a greater number for APS-C cameras, that go from wide-angle (28mm for full-frame, 18mm for APS-C) out to 200mm or even 300mm. Tamron even offers the 16-300mm ƒ/3.5-6.3 Di II VC PZD for APS-C, which provides full-frame-equivalent focal lengths of 24-450mm. These lenses are great when you want to carry just one lens or avoid lens changes (and the resulting dust on the image sensor assembly) in harsh conditions. But because of their wide range of focal lengths, their designs must contain compromises that result in less optimal performance at the wide setting than prime (single-focal-length) or shorter-range zooms that start at 16mm or 18mm. And, of course, 16mm is as wide as they go, while you…