Sony Cyber-shot DSC-H7 Review
The H7 has seven white balance presets (daylight, cloudy, fluorescent 1, 2 and 3, incandescent and flash) in addition to the default auto white balance and a custom (manual) option. In our tests the auto WB system worked pretty well in all outdoor situations (though we did notice a slight warm tone to daylight shots), coped very well with mixed light sources, but struggled to correct the color cast caused by shooting under artificial (indoor) lighting. In fact as the results below show, when pushed, the system is pretty poor. If you want neutral tones in such situations you need to use manual white balance. Interestingly the H7 produced slightly different results to the H9, though there is no pattern to the difference and we put it down to sample variation.
|Incandescent - Auto WB
Red 9.1%, Blue -13.3%
|Incandescent - Incandescent preset WB
Red 6.8%, Blue -9.2%,
|Fluorescent - Auto WB
Red 5.7%, Blue -23.8%,
|Fluorescent - Fluorescent preset WB
Red 7.3%, Blue -10.5%,
The built-in pop-up flash has a range (using auto ISO) of up to around 9.8 m (32 feet) at the wide end of the zoom, dropping to 6.0 m (19.7 feet) at the long end - pretty impressive for a camera in this class (though be aware that at great distances the ISO may get pushed too high for really great quality). We found exposure and color to be very reliable, with the flash quenching well at distances down to about 10cm. There is a slight warm tone to flash photos, but in most cases this is better than being too cool, and produces nice skin tones. One minor complaint is the flash shot-to-shot time (partly due to the pre-flash metering used), which stretches to just over three seconds when red-eye reduction is turned on. If the batteries are low or your subject is a few feet away flash recycle times can rise to as much as 6 or 8 seconds.
|Skin tone - Warm tone,
(H9 example shown)
|Color chart -Slight warm tone,
The H7's macro mode is even better than its predecessor, and lets you get as close as 1cm at the wide end of the zoom, capturing an area 35mm (1.37 inches) across. Obviously there are some limitations on the usefulness of a macro mode than requires you to get so close to the subject for really impressive magnifications. The biggest is the issue of the camera casting such a large shadow over the subject that you can't see it. If you prefer to shoot your close ups from a more respectable distance the long end of the zoom does allow you to get down to around 120cm (about 47 inches) to capture an area just under 10cm across, which isn't bad at all for a zoom this big (though there is some corner softness and mild distortion).
Barrel and Pincushion Distortion
Although the measurements aren't terrible for a camera with such a huge focal length range, the H7 produces images with visibly more distortion than most of its competitors. There is fairly strong barrel distortion at the wide end and noticeable pincushion distortion at all longer focal lengths (not just the longest setting). Of course it always looks worse when shooting test charts, but if you need straight edges (such as copying documents or artwork) then this ain't the camera for you.
|Barrel distortion - 1.7% at Wide angle
Equiv. focal length: 36 mm
|Pincushion distortion - 0.8% at Telephoto
Equiv. focal length: 465 mm
Specific image quality issues
Everything we said about the H9 holds true here too, so we'll repeat it:
Away from the studio in the 'real world', overall impressions of the H7's output are mixed, to say the least. On a positive note the focus, exposure and color are generally excellent (though the default settings may produce output that is a little 'overcooked' for purists). Highlight clipping is fairly well controlled (unless you push the dynamic range too hard), and the sheer versatility of such a wide zoom range - combined with fast focus and an effective stabilizer - means there are few photographic challenges it can't handle.
But look a little closer - particularly at a pixel level - and you start to see the compromises involved in squeezing a 31-465mm equiv. lens and 8 million pixels into such a compact form. We're not sure if it's noise reduction, poor demosaicing or over-compression, but viewed on-screen the images just don't look very pleasant, with visible artefacts and more than a fair share of optical issues.
The main issues are chromatic aberration, purple fringing, particularly at the wide end of the zoom, and excessive noise reduction. The latter causes smearing of low contrast detail (hair, foliage etc) even at low ISO settings and can add a watercolor-like dappling to out of focus areas and other soft details.
In fact at the very widest zoom setting it's kind of hard to find anything really positive to say about the H7's photos; at wider apertures there is a noticeable fall off in sharpness at the edges, strong fringing and an overall lack of crisp detail. If you stop the lens down you get less fringing but diffraction starts to soften the images.
I should stress that unless you're in the habit of printing your images at large sizes or peeping at pixels the H7's output is unlikely to disappoint, and it has a remarkably high 'hit rate', with few focus or exposure failures (obviously the focus 'hit rate' drops as you move towards the long end of the zoom range). But for us the output was uninspiring.
A couple of side notes; firstly the lens hood is definitely useful for reducing flare and should be left on whenever possible when shooting outdoors. Secondly we were surprised to find that even in sunny weather the H7's program mode tended to default to rather small apertures and slow shutter speeds (we're guessing this is to reduce the fringing and edge softness).
This is doubly problematic; over about F5.6 diffraction effects start to soften the H7's output - the lens' sweet spot is around two stops in from the maximum aperture (resolution drops fairly rapidly at higher F numbers), and you can easily end up with shutter speeds too slow to guarantee a blur-free result.
This problem reaches its zenith in the new Advanced Sports Shooting mode, which on a bright day was giving me 1/60th second at F7.1!! This means that all that predictive focus cleverness is totally wasted. This can only be described as a bug in the firmware, and needs to be fixed (there's no way round this either - unlike normal program mode the sports mode doesn't have program shift or ISO control).
Chromatic Aberration & Purple Fringing
All super zoom cameras suffer from some fringing (though Panasonic's processing removes it before you ever see it), and this camera's predecessor (the H5) was the worst offender. The H7 seems to be just as bad, and it is fairly prevalent at the edge of the frame when shooting at the wide end of the zoom and around high contrast edges. Unusually we found evidence of purple fringing even where the edge wasn't particularly high contrast (see example below). There's also fairly strong chromatic aberration at all focal lengths (though most obviously at longer zoom settings), although to be fair it's harder to spot this in normal prints as the fringes are only a few pixels wide in most shots. Either way this whole fringing issue - be it lens related or CCD related - is something Sony really needs to sort out in future models.
|100% crop||92mm equiv., F5.6|
|100% crop||31mm equiv., F4|
|Umbrellas by pleytime|
from An A to Z of Subjects- Week 21, U
|Glass ball on a perforated metal plate _2 by harubux|