White Balance

As we'd expect the DiMAGE X performs best in natural light, with its Auto white balance not doing well under incandescent light. The incandescent preset (Tungsten) was fairly close to our test lamp colour but still left images a little warm. The DiMAGE X does not have a manual white balance feature.

Outdoors, Auto	Outdoors, Sunny	Outdoors, Cloudy
Incandescent, Auto	Incandescent, Tungsten
Fluorescent, Auto	Fluorescent, Fluorescent

Low Light Focus

This test measures the minimum amount of light under which the camera can still focus. The focus target is our lens distortion test chart (shown here on the right), camera is positioned exactly 2 m (6.6 ft) away.

Light levels are gradually dropped until the camera can no longer focus. This is carried out at both wide angle and telephoto zoom positions (as more light reaches the focusing systems with a larger aperture).

This test target is the optimum type of subject for most "contrast detect" AF systems (as it has a vertical line at its center), you should consider the results below the best you could expect to achieve.

Light intensity (Lux) = 2.5 x 2^EV (@ ISO 100), 10.76391 Lux = 1 foot-candle (fc)

This is an average performance for this level of camera at these apertures, the positive note being that if you have enough light to focus at wide angle you'll probably not need any more light to focus at telephoto. 4.0 EV is about as much light as you'd get in a dimly lit living room.

Flash Performance

The DiMAGE X's flash has a rated range of 0.25 - 2.9 m (0.8 - 9.5 ft) at wide angle and 0.25 - 2.3 m (0.8 - 7.5 ft) at telephoto. Interestingly the camera automatically switches to ISO 200 sensitivity when taking flash shots, this is probably to compensate a little for the flash units low power output. Overall flash shots were fairly good at less than 2 m distance, although I found the white balance to be a little too warm (this avoids blue skin syndrome but can leave white walls looking a little pink).

Skin tone test: No visible colour cast, slightly warm white balance and an uneven flash illumination.	Wide angle 2 m wall test: As we'd expect from such a tiny flash unit there's not quite enough power to fill out, evidence of vignetting too (see below).	Here you can clearly see the 'warm' white balance given to flash photos. Warmer colours are preferable for skin tones but this I would say is a little much.

Barrel and Pincushion Distortion

Overall the DiMAGE X produced a little less than the expected lens distortion. Exhibiting approximately 1% barrel distortion at full wide angle and approximately 0.8% at full telephoto.

Barrel Distortion, 1.0% @ wide angle	Pincushion Distortion, 0.8% @ telephoto

Overall Image Quality / Specific Issues

I'll be honest I wasn't overly impressed by the DiMAGE X's image quality. I'm afraid that the whole prism "folded optics" concept simply hasn't come out well. I don't know the physics behind it but the prism is clearly affecting the image quality in a detrimental way, images look blurred and unsharp with a definite 'ghosting' of detail. Colour, metering and overall image balance is good enough but the ability to resolve detail and produce images which look photographic rather than video is sadly lacking.

Ghosting / Softness

One thing which immediately struck me about the DiMAGE X images was that they looked very 'video like', soft with some visible ghosting artifacts. This ghosting was apparent as a shifted (similar to a chromatic aberration shift) of highlighted or shadowed detail within the image, a red or blue artifact on either side of a prominent detail. The X's images were overall also quite soft, this is more clearly defined on the next page of this review in the resolution chart comparison.

Ghosting in visible on our resolution chart as a 'shifted' halo of white (blue) below and red above a black detail.
Again ghosting is visible in this 'every day' shot as well as the softness I was talking of.

Vignetting

This is something I didn't pick up on in my pre-production review but became very apparent when browsing thumbnails of DiMAGE X images. When an image is reduced in size the vignetting effect (darkened corners) tends to be more visible. This appeared to occur at focal lengths between full wide angle and mid-zoom. In the sample below you can clearly see vignetting in the thumbnail image on the left, to make it more visible I've increased the contrast of the image, now it's really quite visible.

Normal thumbnail of image (click for original)	Increased contrast to make vignetting more visible