One of the biggest benefits of CMOS sensors is their fast speed compared with CCD sensors. That's certainly true of the 100 HS, which shows a noticeable performance jump from its predecessor, the CCD-based Canon PowerShot SD1300 IS. On the other hand, it is slightly slower than CMOS-based ultracompacts from other manufacturers. The camera goes from off to first shot in 1.4 seconds, with shot-to-shot times averaging 1.9 seconds without flash and 3.4 seconds with flash. Its shutter lag--the time it takes from pressing the shutter release to capturing a photo--is 0.3 second in bright lighting and 0.6 second in low-light conditions.
The camera's regular continuous shooting option is capable of capturing at 3.3fps, with focus and exposure set with the first shot. It can shoot until your memory card fills up, though, which is nice, as competing cameras have a burst limit and make you wait while images are stored before you can shoot again. The camera also has a high-speed burst mode that can shoot 3-megapixel photos at up to 8.2fps. The results are very good compared with similar modes on other cameras I've tested, suitable for small prints and definitely for Web use.
More of issue for me is the camera's autofocus performance. When shooting in Smart Auto, it frequently locked onto the wrong subjects, forcing me to prefocus with a half-press of the shutter release again and again. Most of the time that wouldn't work and I'd end up switching to using the tracking AF option, which helped but only really with stationary subjects. Or you can switch to Program mode and select center focus, which is how I shoot most of the time anyway for this reason. It is frustrating, and if you generally don't prefocus before you shoot, you may end up with your subject frequently out of focus.
The look and design of the 100 HS has changed slightly from its predecessor, the SD1300 IS. It's fractionally smaller, but has a larger LCD--3 inches rather than 2.7 inches. The shooting-mode switch is now on top and in its place is a one-touch record button for movies. All of the controls are flat and flush with the body. It gives the camera a very smooth appearance, but using the four-way directional pad and center Func/Set button can be a little difficult. They do feel easier to press than on past models, though. Also, while I had no problems using them, the buttons, shooting-mode switch, and zoom rocker are tiny, which might be a problem for some; it would be an excellent idea to lay hands on one before you buy it.
Regardless of their shape and size, the controls are easy to master. The menu system can take some getting used to depending on how quickly you can remember to hit the Func/Set button for shooting-mode specific settings and the Menu button for everything else. You also have the option to turn on a help system with hints and tips for choosing the appropriate settings or simply telling you what the shooting mode you're in is going to do. It's not uncommon to find, but Canon does a nice job of it. The next step would be to put a full, searchable user manual on it since there's no printed manual included.
For connecting to a computer, monitor, or HDTV there are Mini-USB/AV and Mini-HDMI outputs underneath a small door on the right side of the body. The battery and memory card compartment is on the bottom under a nonlocking door. The battery does not charge in camera, and the shot life is rated at 230, so you'll probably find yourself opening the compartment quite a bit if you shoot regularly. Keep in mind, too, that using the zoom or burst shooting a lot, shooting full HD movies, and keeping the screen brightness high will all cut into your battery life.
If you're looking for an inexpensive, simple, but still feature-filled ultracompact, the Canon PowerShot 100 HS is a safe bet. That's in spite of its autofocus issues and somewhat soft photos.
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