Fujifilm X-S1 Digital Camera Review$799.95
Image sharpness is a weak point with the X-S1. The results aren't poor, just mediocre. The overall average is a middling 1120 MTF50s across all focal lengths, apertures, and areas of the photo frame.
At the widest aperture at the wide-angle setting at the center of the frame, images are nice and crisp—we measured about 1800 horizontal and 1900 vertical MTF50s, which are very good results. But then the aperture shrinks or the focal range increases (particularly near the telephoto setting), sharpness falls off quickly. Performance is universally muddy midway between the edge and the center of the frame, too.
In its defense, the X-S1 doesn't apply quite as heavy a dose of border enhancement as most superzooms tend to do. The Canon SX40 HS, for example, earned an outstanding sharpness score thanks to artificial pixel sharpening, but whether the SX40's shots really look much sharper is debatable. We tested the X-S1 with pixel sharpening set to standard; had we bumped it up to a higher level, it probably would've earned a better score.
The point to take away here is that the X-S1 offers plain ol' superzoom sharpness out of a camera that costs nearly twice as much as its nearest competitors. The lens just doesn't live up to the sensor's potential. More on how we test sharpness.
Any camera with a 26x zoom lens had better have a strong stabilizer, and the X-S1 does. The X-S1 already has two design elements working in its favor: a huge grip, and an eye-level finder, both of which make it easier to hold a camera steady. Beyond that, the optical stabilization is very effective. We measured a 64.3 percent improvement in stabilization at the telephoto setting with stabilization activated. The difference is visible even in the viewfinder—little shakes don't appear on-screen when IS is turned on.