Ricoh GR II Optics

Fixed 18.3mm lens
Excellent far-field performance from the 18.3mm f/2.8 fixed lens.

The Ricoh GR II is equipped with a fixed 18.3mm f/2.8 lens, with a 35mm-equivalent focal length of about 28mm. Construction consists of 7 elements in 5 groups including two double-sided aspherics, with a 9-bladed diaphragm providing an aperture range of f/2.8 to f/16. There's a built-in 2 EV neutral density filter as well.

Sharpness and contrast are excellent at f/8 across the frame, and chromatic aberration is quite low (see below for more on that). Performance in the corners looks to be quite good (difficult to evaluate in this image), with just a hint coma distortion. There is some visible corner shading ("vignetting"), though. See below for test results on macro mode, geometric distortion, corner performance, chromatic aberration, etc.

The Ricoh GR II does not offer traditional "digital zoom", but it does offer a 35mm-equivalent crop mode that produces 10.3-megapixel images with no upsampling.

Macro
A larger-than-average minimum coverage area, with good performance. Flash exposure is offset at closest range, but it throttles down well.

The Ricoh GR II captures a fairly large minimum area measuring 4.27 x 2.83 inches (109 x 72 millimeters) in Macro mode. Sharpness is quite good over most of the frame at f/8, with only minor softening in the corners. (Most lenses have some softening in the corners at macro distances, but the GR II's lens does better than most.) The flash throttled down well, but coverage is not very even, illuminating the top left portion of the frame better than the bottom right, so plan on using external lighting for macro shots at closest distance.

Geometric Distortion
Very low geometric distortion.

The Ricoh GR II's lens produces only about 0.1 percent of complex (wavy) barrel distortion, which is very low, especially for a wide-angle lens. Uncorrected RAW files exhibit the same low distortion, which is a pleasant surprise (most compact wide-angle lenses are digitally corrected for distortion these days). 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).

Chromatic Aberration and Corner Sharpness
Very low levels of C.A. (and the camera suppresses what little there is). Very good corner performance even wide open, though with visible shading.

Chromatic Aberration. Chromatic aberration in the corners of in-camera JPEGs is fairly low even when wide open, while the center of the image shows almost no CA. Stopping-down to f/5.6 or f/8 reduces the number of colored pixels, but they are slightly more distinct. Still, CA is very low in JPEGs.

Corner Softness. Wide open at f/2.8, the GR II's lens exhibits surprisingly good sharpness in the corners while the center is very sharp. When stopped down to f/5.6 sharpness in the corners improves slightly, however the center is still slightly sharper. At f/8, we start to see slight softening across the frame due to diffraction. Still, really excellent performance across the frame.

Corner Shading. The Ricoh GR II's lens produces visible corner shading ("vignetting") even when stopped down compared to the center of the frame, even though shading correction is applied to JPEGs by default.

Lens Corrections

The Ricoh GR II appears to apply chromatic aberration suppression and some shading correction which can be disabled (it's enabled by default) to its JPEGs, however geometric distortion is the same as uncorrected RAW files.

Chromatic Aberration Suppression and Shading Correction

As you can see, lateral chromatic aberration is a little higher and brighter in the uncorrected RAW file (above right), however it's still fairly low. We measured about 0.9 EV of corner shading in RAW files versus about 0.5 EV in JPEGs wide open at f/2.8. And corner shading only reduces to about 0.8 EV and 0.4 EV respectively at f/8.

Overall, an excellent lens that's sharp from edge-to-edge even wide-open, with low distortion and minimal chromatic aberration, but with some noticeable corner shading especially in uncorrected RAW files.

Coverage
Excellent accuracy from the LCD monitor.

The Ricoh GR II's LCD monitor shows about 100% horizontal coverage in record mode, but vertical coverage is a bit higher. This is excellent performance, though not a surprise given the low-distortion lens and the fact that the preview image is derived from the imaging sensor.