An all-in-one "walking around" zoom lens is what's normally on my cameras. I like them because they're more versatile than a fixed focal length lens and have more reach than the typical 24-70mm pro zoom. (They don't have as much reach as a superzoom. In non camera nerd speak, these are "5X" rather than "10X" zooms.)
The lack of focal length, however, is made up for by much better optics as well as larger available apertures over the most of the range of the lens. For instance, my favorite Nikon full-frame superzoom, the 28-200mm f/3.5-5.6, has a maximum aperture of f/3.5 at 28mm, while the 24-120mm f/4 VR is a third of a stop slower. But by the time you've zoomed out to 50mm, the 28-200 can only manage f/4.5, while the 24-120 will hold f/4 all the way out to 120mm.
The bigger hole lets in more light, allowing you to use lower ISOs or faster shutter speeds indoors or in the shade.
These lenses tend to be compact, but still fairly chonky, and that's one reason that smaller sensor cameras still appeal to me.
Thanks to the magic of crop factor, these are the equivalent lenses for full-frame, APS-C, and Micro 4/3rds:
- Nikon 24-120mm f/4 VR: 84x103.5mm, 710g
- Fuji 16-80mm f/4 OIS WR: 78x89mm, 440g
- Panasonic 12-60mm f/2.8-4: 68-86mm, 320g
That Micro 4/3rds lens on the Olympus, seen in the photo above, is almost an inch shorter, about a half inch smaller in diameter, and less than half the weight of the full-frame Nikon, yet it covers the same effective field of view and is a full stop brighter on the wide end, to boot.
That's just shy of a pound's weight difference between the Nikon and Panasonic glass, and you notice that when it's hanging around your neck during a long day.
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