Specific Image Quality Issues
On the positive side the Z5 produces the kind of bright, saturated images that make for very appealing prints with the minimum of post-processing. The images are a little soft, but - as long as you stick to lower ISO settings - they sharpen up nicely, and have plenty of detail for prints up to about 8x10 inches.
Exposure is very consistent, though there is a slight tendancy towards underexposure, meaning blocked-in shadows in contrasty scenes (I personally thought the default contrast setting is a little too harsh, which doesn't help matters). The reason for the slight underexposure would appear to be a conscious decision on the designers' part to avoid blown highlights, something the Z5 (in common with most 5 megapixel cameras) suffers from whenever the scene being photographed is bright and contrasty. It's considerably easier to lift shadow detail than to restore highlight detail that was never captured in the first place, so don't be tempted to increase exposure slightly if the on-screen images look a little dark.
Noise seems to be the Z5's achilles' heel; the top ISO setting of 320 is unusually low, but so, noise is a serious issue at ISO 200 and 320. The noise is so strong at ISO 320 that it obliterates far too much fine detail, so basically you're best avoiding the setting unless you have no other way of getting the shot.
Our only other major complaint is focus, which seems to hunt excessively in low light or with low contrast subjects, and - as with other Konica Minolta cameras we've tested - will on occasion indicate correct focus when it hasn't been found, resulting in a totally out of focus image.
Purple fringing and blooming
Big zooms are usually plagued by chromatic aberration, but the Z5's images are admirably fringe-free. In fact you need to try very hard to get any fringing at all - I could only find two examples of it in over 350 shots taken in a wide variety of situations. The problem seems worse when - as here - the image is slightly blurred due to mis-focus or camera shake, but it is so rare it's not worth worrying about.
|420 mm equiv., F5.6|
|Click for a larger image||Click for a movie of the Anti-Shake system in action (exaggerated motion) - 2.1 MB|
The DiMAGE Z5 implements the same image stabilization system as the A2/A200 (and the new 7D digital SLR). By placing the CCD sensor on a movable platform supported by two actuators (horizontal and vertical) the system can compensate for a certain amount of the blur caused by camera shake at lower shutter speeds and longer focal lengths. The system works by analyzing input from motion detectors in the camera body and producing an inverse movement in the CCD. The system can be disabled easily (by pressing a very prominent button on the rear of the camera) and can also detect a panning movement and only compensate for movement on the opposite axis. Konica Minolta claims that its system enables shutter speeds of eight times longer (three stops) than you would be able to manage without it.
In use we found the combination of handling (fairly weighty, very well balanced, good ergonomics) and the AS system to be incredibly effective in most shooting situations. At wideangle it is perfectly possible to hand-hold exposures down to 1/4 of a second - I even had some success with exposures as long as a second, provided that I held the camera in both hands and braced myself (elbows tight against the chest). At the telephoto (420mm) end of the range you can easily shoot at 1/80th of a second without worrying too much about camera shake (though I'd always take a few shots to be sure). All this would seem to support Konica Minolta's claims for a three-stop advantage when using AS. Of course if you don't have a very steady hand or are shooting in high winds you'll soon find that extreme motion simply can't be corrected (the CCD cannot move far enough), but I'd certainly suggest the AS system on the Z5 is as effective as the optical IS found on the Panasonic FZ series until you get to the very long end of the zoom.
Below are a couple of comparative 'real world' examples. Note also that all the images in the samples gallery are hand held.
|AS effectiveness at 1/50 sec, 420mm equiv. focal length, handheld|
|AS on 100% crop||AS off 100% crop|
|AS on 100% crop||AS off 100% crop|
It is obvious from the examples above that even with a long exposure (here around three stops slower than would normally be recommended for this focal length), the AS system makes low light hand held photography possible.