In charge of holding their secrets, since not a day goes by that I don’t hear about this or that new patent or camera just around the corner. Maybe it’s just their canny marketing division seeding leak sites, and if so, bravo. But to business: if you are a millionaire, this is probably a post for you, since everything involved is high-end. I know we’re a big source of news for the fantastically rich, so I thought I’d write it up.

The rumor is that next week, Canon will be firing off a 1D mk IV in our general direction that sports a whopping 32 megapixels. I can’t be the only one that thinks that’s not only not true, but absolutely ridiculous. I can see 20 with an ISO improvement, but 32? Why not 50, guys? That’d be just as useful to the guys who use 1Ds.

The other rumor is that we may finally see a 24-70mm f/2.8 IS lens. The 24-70 f/2.8 is widely considered Canon’s most versatile lens, for good reason, and an IS variant would almost certainly be welcome. I’ve always avoided getting one because I’d really like another stop… and also because it costs $1300. That’s the other thing. A replacement L lens means all the serious gearheads will be unloading their old one, so in a week or so we might see a glut of old 24-70s on Craigslist or eBay for insane prices. I’m looking forward to it, even though I haven’t got two dimes to rub together these days.

Canon and Nikon sell a wide range of zooms. Many are "consumer" zooms: reasonably high quality lenses with a few limitations and a low price. More expensive and higher performance "professional" lenses are also available. This article looks at the more popular models of these professional zoom lenses.

Professional zoom lenses are usually brighter (large maximum aperture) than the consumer equivalents. A maximum aperture of f2.8 is common, and is constant for the entire zoom range. None of the variable f3.5 to f5.6 nonsense seen on consumer zooms (the maximum aperture decreases as the lens is zoomed in). An f2.8 lens is 4 times (2 stops) brighter than an f5.6 lens.

Almost all professional zooms will use ultrasonic autofocus motors (Canon USM, Nikon AF-S) for quiet operation. However image stabilization (Canon IS, Nikon VR) isn't always provided.

Professional Canon lenses are easily identified by the "L" in their designation (example: EF 24-70mm f2.8L USM), which stands for "Luxury". They also have a thin red band on the lens barrel. Some 1.6x crop (EF-S) lenses are practically L quality, but Canon appears to reserve the L designation for full frame 1x crop (EF) lenses only.

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