Olympus E-P5 Optics

Prime Lens
Excellent far-field performance from the 17mm f/1.8 kit lens.

The Olympus E-P5 is available bundled with an Olympus M.ZUIKO 17mm f/1.8 Micro Four Thirds lens. This moderately wide-angle lens has a 35mm-equivalent focal length of about 34mm because of the E-P5's 2x "crop factor."

Far-field performance was excellent at f/8, with strong detail and very good contrast across the frame, with little sign of flare. Mild to moderate lateral chromatic aberration can be seen in the corners and edges, though, as the camera does not suppress C.A. like most competing models these days. Overall, though, excellent performance here.

Because the lens is so sharp, the camera's 2x digital zoom worked fairly well, and should come in handy when you need some extra reach with this wide-angle prime. See below for comments on macro performance, geometric distortion, corner performance, etc.

Macro
A very large minium capture area, with good detail. Flash exposure is uneven.

The Olympus PEN E-P5's macro performance will depend entirely on the lens in use. With the 17mm f/1.8 kit lens (which is obviously not a macro lens), the Olympus E-P5 captured a large minimum area measuring 5.22 x 3.92 inches (133 x 100 millimeters). Sharpness is quite good over most of the frame, though corners are a bit soft. (Most lenses have some softening in the corners at macro distances.) The flash throttled down well, but provided quite narrow and offset coverage at closest focus, resulting in an unevenly illuminated and slightly underexposed image.

Geometric Distortion
Very low geometric distortion with the 17mm kit lens in JPEGs. High barrel distortion in uncorrected RAW files.

When shooting JPEGs, the Olympus PEN E-P5's 17mm kit lens produced about 0.2 percent barrel distortion depending on where it's measured, which is very low almost negligible. 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).

To see how much correction is taking place in the camera, we converted RAW files from the above shots with dcraw, which does not correct for distortion. As you can see, uncorrected barrel distortion is quite high at about 2%. We expect to see high distortion at wide angle from smaller interchangeable lenses though, so it's nothing to be concerned about unless you are using a raw converter which does not understand the embedded "opcodes" to perform distortion corrections automatically. Most RAW converters these days are capable of applying distortion correction automatically, as specified by the manufacturer. (There is however going to be some loss of resolution as a result of such correction, because pixels in the corners of the frame are being "stretched" to correct for the distortion. Obviously, a lens that doesn't require such correction, and is also sharp in the corners to begin with would be preferable, but relaxing constraints on barrel and pincushion distortion likely brings other benefits in the lens design, such as cost, size and weight.)

Chromatic Aberration and Corner Sharpness
Moderate chromatic aberration with the 17mm kit lens, but with excellent sharpness across the frame.

Chromatic Aberration. Chromatic aberration in the corners with the E-P5's 17mm kit lens is moderate in terms of pixel count, but a little bright and noticeable both wide open and especially when stopped down to f/8. In both cases, though, the color fringing gradually reduces in brightness and width as it approaches the center of the image, where it is practically nonexistent.

The Olympus E-P5 does not appear to be suppressing lateral chromatic aberration in its JPEGs, as uncorrected RAW files have similar amounts.

Corner Softness. The Olympus E-P5's 17mm kit lens is quite sharp across the frame even wide-open, with only minor softening in the top corners at f/1.8. The bottom corners are pretty sharp, while the center is very sharp. This is excellent performance, especially given the speed (brightness) of the lens. Corners sharpness improves when stopped-down to f/8, to almost as sharp as the center. Again, excellent.

Vignetting. There's some moderate vignetting (corner shading) when the lens is wide open, as indicated by the darker corner crop at f/1.8 compared to the center, but shading is negligible when the lens is stopped down to f/8. See below for optional Shading Compensation.

Shading Compensation
The Olympus E-P5 features optional Shading Compensation to reduce vignetting in JPEG images.

Mouse over the links above to compare thumbnails, and click on the links to load the full resolution images.

As you can see, the Olympus E-P5's Shading Compensation automatically reduces corner shading with the 17mm kit lens, and is a useful feature when shooting JPEGs at wide apertures.

Shading Compensation is off by default, not available when using teleconverters or extension tubes, and may produce more visible noise in the periphery at higher ISOs.

Accuracy
Excellent accuracy from the LCD monitor and VF-4 EVF.

The Olympus E-P5's LCD monitor and VF-4 electronic viewfinder (available separately or in a kit) both proved very accurate in record mode, showing essentially 100% coverage with our Olympus Zuiko Digital 50mm f/2.0 low distortion prime. Excellent results here.