Fujifilm X70 Optics

Fixed focal-length lens
Excellent far-field performance from the 28mm equivalent fixed lens.

The Fuji X70 features a fixed, 18.5mm f/2.8 wide-angle lens with an equivalent focal length of 28mm thanks to the APS-C-sized sensor's ~1.5x crop factor. Sharpness and contrast are very good across the frame at f/8, with very low levels of coma distortion, negligible chromatic aberration and flare, and very little softening in the corners. Excellent results here.

Macro
The Fuji X70 captured a larger-than-average minimum area, with very good detail in the center. The flash slightly overexposed the shot at closest focus.

The Fuji X70 captured a somewhat larger-than-average minimum area measuring 3.70 x 2.46 inches (94 x 63 millimeters) at its closest focus distance. Sharpness is very good over much of the frame at f/8, but corners show strong blurring. (Most lenses have some softening in the corners at macro distances.) The Fuji X70's flash didn't throttle down enough, producing a slightly overexposed image that is unevenly illuminated due to the flash's off-center location.

Geometric Distortion
Low to moderate distortion from the Fuji X70's fixed, wide-angle lens.

The Fuji X70's 28mm equivalent lens produced just under 0.2 percent complex pincushion distortion along the top and bottom edges which is lower than average, especially for a wide-angle lens. Vertical pincushion along the sides is moderate, though, at about 0.5% percent. The distortion's complex nature makes it more difficult to correct in software without lens profiling, though it's low enough that it probably requires no correction for all but the most critical applications. The camera does not appear to be applying geometric distortion correction to its JPEGs, as uncorrected RAW files contain identical amounts. This is the tendency for the lens to bend straight lines outward (like a barrel -- usually at wide-angle) or inward (like a pincushion -- usually at telephoto). A very good performance here.

Chromatic Aberration and Corner Softness
Low chromatic aberration in JPEGs, though higher in uncorrected RAW files. Minor blurring in corners when wide-open but excellent corner performance stopped-down.

Chromatic Aberration. Chromatic aberration in the corners of JPEGs is quite low and dull, and hardly noticeable. In the center, it is practically nonexistent. (This distortion is visible as a slight colored fringe around the objects at the edges of the field of view on the resolution target.)

Corner Softness. The Fuji X70's lens produced some blurring in the corners wide-open at f/2.8, though it was fairly minor but it did extend pretty far into the frame. The center of the image however is quite sharp and contrasty. At f/5.6 and f/8, corners are only slightly softer than the center, which is very sharp. Excellent performance when stopped down.

Corner Shading. Moderate corner shading ("Vignetting") is visible in JPEGs, as indicated by the dimmer corner crops, and stopping down only reduces it slightly. (More on corner shading below.)

Chromatic Aberration Correction. The Fuji X70 appears to suppress chromatic aberration during JPEG processing, as do most cameras these days. Above are crops comparing an in-camera JPEG (left) to the matching uncorrected RAW file converted with dcraw. As you can see, lateral chromatic aberration is almost nonexistent in camera JPEGs, but is still moderately low in the dcraw conversion even at maximum aperture. Also notice the strong halos generated along outside edges by the camera's rather aggressive adaptive sharpening algorithm.

Corner Shading Correction. The Fuji X70 applies corner shading correction to JPEGs as well, and RAW files have an embedded profile to correct for shading. As you can see in from the uncorrected dcraw conversion above right which is roughly the same brightness in the center of the frame, there is significant shading at f/2.8. Note that when converting files with Adobe Camera Raw, the shading correction specified by the built-in profile cannot be disabled.


Overall, excellent performance from the Fuji X70's 28mm equivalent lens.

Accuracy
Very good accuracy from the LCD monitor in record mode.

The Fuji X70's LCD monitor proved fairly accurate, showing about 99% coverage in record mode. While this is very good, we usually see close to 100% coverage from an electronic preview.