White Balance

As you can see below the EX-Z3's automatic white balance appeared to work well under natural light. The only preset which worked acceptably was the incandescent preset. Better news on the manual white balance front however, this worked virtually flawlessly in any light.

Outdoors, Auto	Outdoors, Shade	Outdoors, Manual
Incandescent, Auto	Incandescent, Incandescent	Incandescent, Manual
Fluorescent, Auto	Fluorescent, Fluorescent	Fluorescent, Manual

Macro Focus

As we found in our Optio S review this little Pentax lens takes pretty good macro shots. Switch to Macro focus mode and the zoom range is automatically limited from wide angle to half-zoom, closest focus distance is 6 cm. Half-zoom is the optimum position for the best frame coverage, we measured it as a horizontal frame coverage of 35 mm (1.4 in). Excellent.

Flash Performance

The EX-Z3's flash unit has a specified range of 2.3 m (7.5 ft) at wide angle and 1.5 m (4.9 ft) at telephoto. Unfortunately in our tests it produced a cool 'blue cast' in images, this is clearly a failing of the camera's automatic white balance. The exposures were actually well metered and flash power well judged. A disappointment.

Skin tone - Good exposure, poor white balance, blue cast	Color patches - Good exposure, poor white balance, blue cast

Night exposures

The EX-Z3 has very limited night exposure abilities, switch the camera into 'Night Scene' Best Shot mode and you can take exposures of up to 1 second in duration. I also chose to switch white balance from Daylight (the 'Night Scene' default) to Incandescent for the shots below. I did attempt to brighten the image by increasing sensitivity from ISO 100 to ISO 200 however the camera simply chose to halve the shutter speed and produce almost the same result (but with more noise).

Night exposure: ISO 100, 1 sec, F2.6
Night exposure: ISO 200, 1/2 sec, F2.6

Barrel and Pincushion Distortion

Not surprising really (as they share the same lens) but the EX-Z3 produced exactly the same amount of distortion as the Pentax Optio S. Above average barrel distortion at wide angle but no measurable pincushion distortion at telephoto.

Barrel Distortion, 1.4% @ wide angle	Pincushion Distortion, none @ telephoto

Vignetting / Light fall off

Our vignetting / light fall off test is very simple, a shot of a blank wall from two meters away, vignetting will always be most visible at wide angle and maximum aperture and will start to disappear at smaller apertures and/or further zoom. Same lens, same results (as the Optio S), the EX-Z3 exhibited some vignetting at wide angle, specifically on the right hand corners of the image. It is possible that such vignetting could be seen in certain shots.

Slight corner vignetting visible at wide angle and maximum aperture (F2.6)	No vignetting at telephoto

Purple Fringing (Chromatic Aberrations)

The EX-Z3 did exhibit some purple fringing near the corners / edges of images shot at wide angle and maximum aperture (F2.6). This is undoubtedly a consequence of the tiny lens system. The sample on the left was the only one in our 100+ test shots in which CA was visible, this is right at the edge of the frame and the image is slightly out of focus.

Some fringing visible in the corners of shots with high contrast	Our standard chromatic aberration test shot

Overall Image Quality / Specific Issues

The EX-Z3 can produce sharp images with good detail and no major issues. Color balance was some how 'different' with especially blues appearing more muted (darker?) than other cameras. The EX-Z3's images to tend to have a more 'video like' look to them than we saw from (for instance) the Pentax Optio S. This may have something to do with the EX-Z3's tone curve and its tendency to simply clip highlights to white in sudden manner. This particular camera didn't exhibit the 'bottom of lens softness' issue identified in my Pentax Optio S review.

Red Overexposure Color Shift

This is a fairly rare issue in modern digital cameras, however the EX-Z3 clearly exhibits it in the image below. The guards red jacket in direct sunlight has been pushed into overexposure (red channel is 255) and the levels of the other channels causes the color to shift to orange. You can see the true color of the jacket bridge to the right of the image.