Sony RX10 II Optics

Zoom
A very versatile 24-200mm equivalent zoom range, with excellent performance.

The Sony RX10 II is equipped with a 8.8-73.3mm f/2.8 lens, offering a zoom ratio of about 8.3x for a very versatile 35mm-equivalent focal range of about 24-200mm.

Far-field performance appears to be excellent at f/5.6, with very good sharpness and contrast across most of the frame throughout the zoom range, and only minor softening and coma distortion in the extreme corners. Chromatic aberration is fairly low (like most cameras, the RX10 II suppresses it), and flare appears to be well-controlled. This scene isn't great for judging distortion or performance in the corners, though, so see below for lab results on corner softness, geometric distortion, macro performance, etc.

Like other recent Sonys, the RX10 II offers Clear Image Zoom up to 2x and standard digital zoom up to 4x, however we did not test those features in our lab results.

Macro
A larger than average sized minimum coverage area, with very good detail. Flash worked fairly well at full telephoto.

The Sony RX10 II captured a slightly larger than average sized minimum area measuring 2.98 x 1.99 inches (76 x 51 millimeters) at full telephoto, which is very similar to the maximum reproduction rate at wide angle. Detail is excellent across much of the frame, though corners show a bit of softness even at f/8 (most lenses show some softening in the corners at macro distances). Unlike at maximum wide angle where the RX10 II's formidable lens casts a large, very dark shadow when using the built-in flash, at full telephoto the flash worked fairly well producing a good though slightly dim image, and the lens casts no shadow.

Geometric Distortion
Very low distortion in camera JPEGs, much higher in uncorrected RAW files.

Geometric distortion in JPEGs is well-corrected, with only about 0.3% barrel distortion at wide angle, and under 0.1% barrel distortion at full telephoto. 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).

Unsurprisingly, uncorrected RAW files show fairly high geometric distortion. We measured about 2.1% barrel distortion at maximum wide angle, and about 1.6% pincushion distortion at full telephoto. That's not unusual, though, and most RAW converters should automatically correct for it, but strong correction can lead to some additional softness in the corners.

Chromatic Aberration and Corner Sharpness
Very low to moderately low chromatic aberration at wide angle; fairly low levels at full telephoto. The lens produced some soft corners wide-open, though corner sharpness improved stopped-down.

Chromatic Aberration. Lateral chromatic aberration in camera JPEGs is well corrected, with moderately low amounts in the corners at wide angle, and fairly low amounts and telephoto, though you can see that some edge acuity it lost in the corners from suppression particularly at telephoto. The center shows very low levels of C.A. at wide angle but higher levels at telephoto, though still fairly low.

Corner Softness. Sharpness and corner performance is generally very good for the type and speed of lens, though our copy appears to have a slightly decentered element or group (unfortunate, but not at all unusual). In our sample, at maximum aperture (f/2.8), corner performance is fairly symmetrical at wide angle and sharpness is pretty good, while the center is tack sharp. At full telephoto however, the bottom corners are quite soft and softness extends far into the frame, however the top corners are fairly sharp, while the center is sharp, though not quite as sharp as maximum wide angle. Note that some of the corner softness is due to strong distortion correction, both geometric and chromatic aberration (see below for uncorrected results).

Vignetting. You can also notice some minor corner shading ("vignetting") from the darker corner crops particularly at full telephoto.

F5.6: Interestingly, stopping down to f/5.6 at wide angle actually produced some slightly softer results in both the corners and center, though contrast, chromatic aberration and vignetting improved. Stopping down to f/5.6 noticeably improved sharpness in the corners at full telephoto, especially for the lower corners, while also improving contrast and shading, though the center remained about the same, still not quite as sharp as wide angle.

F8: Here we see the effect of stopping down to f/8. At wide angle, the corners and the center lose a bit of sharpness due to diffraction. At full telephoto, the worst-case left corners improve, but the others as well as center aren't quite as sharp. Vignetting is further reduced, but still visible at full telephoto.

Chromatic Aberration Suppression. As mentioned previously, lateral chromatic aberration in camera JPEGs is well corrected, with low to moderately low amounts at wide angle and telephoto. As you can see from the uncorrected RAW crops (above right), lateral chromatic aberration is actually quite high and bright at maximum wide angle, and moderately high though not nearly as bright at full telephoto, so the Sony RX10 II's processor does a good job suppressing most of it in JPEGs.

Overall, very good to excellent performance for a 24-200mm equivalent f/2.8 constant aperture lens.

Coverage
Excellent accuracy from the electronic viewfinder and LCD monitor.

The Sony RX10 II's electronic viewfinder and LCD monitor both showed essentially 100% coverage at wide angle and at full telephoto, which is excellent, especially given the amount of geometric distortion correction being applied.