Image quality
Framing accuracy
The pink area shows the extent to which the LCD viewscreen monitor displays the scene and the surrounding blue and black areas are unseen and so wasted
In best resolution mode the recorded resolution is 2272x1704 or 3,871,488 pixels. The above image shows that actual useful coverage is 2194x1650 or 3,620,100 pixels, meaning 250,000 pixels or so are wasted, making the actual coverage about 93.5%, with 6.5% wastage and this is about typical for the class.
Colour
The picture above was taken at almost noon under the light of a December sun. Winter sun is naturally warmer than mid-summer sunshine, but the natural warmth of the 420Z has accentuated the richness of tone here.
Gretag Macbeth DC Color Chart
Konica Revio KD-420Z
Olympus Mju:400
Above is a simple comparison of shots of a Gretag Macbeth ColorChecker DC chart taken with the 420Z (top) and an Olympus Mju:400.
The Mju:400 is one of the better cameras in this class with regard to colour reproduction. The 420Z, by comparison, shows a tendency to over-saturation and warmth that is typical of many consumer cameras. It's not necessarily a bad thing if you are mainly taking holiday and family snaps as it does make the pictures more attractive.
Fluorescent colours
DayGlo fluorescent colours are very difficult to reproduce well, photographically – using digital or film methods. The 420Z hasn't really managed to capture the true appearance of our fluorescent card test here. The yellow looks quite muddy and the green looks too yellow.
Nature
It can't be said that the 420Z's over-saturated and warm colour characteristics result in accurate reproduction of natural colours like the green of the leaves above or the orange in the berries, but this bias is preferable to a cold or blue-ish alternative shown by some cameras.
Exposure metering
In the scene above the metering system has done a good job of disregarding the dark margins of the scene and exposed correctly for the central area of the scene seen through the bridge.
However, in the second scene above, the sky has caused the metering system to underexpose the mid and foreground areas of the picture.
Overall, the 420Z's metering performance is about average of its class – it gets undemanding scenes right, works well when the central area is surrounded by dark areas but can be fooled by bright skies. This is typical of a centre-weighted metering system, which the 420Z uses. A smarter matrix mode metering system should be less prone to mistakes. A tighter central spot zone meter mode is available.
White balance
Once again, the typically warm balance of the camera in general is evident here. It was not easy to get neutral or cool whites under any lighting conditions. This can be corrected out of the camera of course, but the 420Z's performance was really only average in this respect.
Sharpness
Konica Revio KD-420Z f/3.8 60mm (equiv) zoom
Olympus Mju:400 f/4 60mm (equiv) zoom
Konica Revio KD-420Z f/6.4 60mm (equiv) zoom
The ISO resolution test target shows that compared to the Olympus Mju:400 at around f/4 with the zoom set to an equivalent setting of 60mm, there is a similar performance. The 420Z result looks less sharp because the camera appears not to sharpen the image as much as the Mju:400 does.
Resolution suffers when the aperture is reduced to f/6.4 on the 420Z, which may explain why there are only two aperture settings available at any one time.
Noise
Noise was never perceived as a noticeable problem with the 420Z unless manually switching to the higher ISO settings. The low noise performance can be explained through the high efficiency of the camera's DSP image processor and the relatively modest amount of in-camera sharpening.
Fringing
Very good marks are scored by the 420Z when it comes to resistance to purple fringing. Above is a 1:1 reproduction of the corner of a frame that, with some other cameras, would show noticeable blue or purple halos along the high contrast edges of the branches. With the 420Z we can see it is practically non-existent.
Lens flare
As this almost head-on shot into the sun shows, the 420Z's lens does quite a good job of suppressing flare.
Distortion
Konica Revio KD-420Z widest zoom setting
Konica Revio KD-420Z mid-zoom setting
Konica Revio KD-420Z full tele zoom setting
Here we have another very good performance from the 420Z. At the widest zoom setting, barrel distortion is well-controlled and almost gone by the mid-zoom setting. At full telephoto there is only the tiniest amount of pinchushion distortion visible.
Close focus
Konica Revio KD-420Z closest focus coverage at full telephoto zoom
Konica Revio KD-420Z closest focus coverage at widest zoom setting
Best close focus coverage is achieved with the 420Z using the wide angle end of the zoom, though the price paid is some barrel distortion bowing of the result.
Movie mode
The movie mode of the 420Z is nothing special, though it does record a mono sound track. Only a QVGA resolution mode is offered and the action is as jerky as you would expect from most cameras in this class.
