Digital Cameras - Konica Minolta DiMAGE Z10 Test Images
I've begun including links in our reviews to a Thumber-generated
index page for the test shots. The Thumber data includes a host of information
on the images, including shutter speed, ISOsetting, compression setting,
etc. Rather than clutter the page below with *all*that detail, we're posting
the Thumber index so only those interested inthe information need wade through
it!
High resolution and a lot of fine detail. Pretty good white balance,
but skin tones are very pink, and exposure was very inconsistent.
The extreme tonal range of this image makes it a tough shot for many
digicams, which is precisely why I set it up this way, and why I shoot
it with no fill flash or reflector to open the shadows. The object is
to hold both highlight and shadow detail without producing a "flat"
picture with muddy colors, and the DiMAGE Z10 handled the challenge pretty
well, but its color was rather oversaturated, and it had some exposure
difficulty.
The shot at right was taken with a +0.3 EV exposure
compensation adjustment, which results in slightly dark midtones and very
dark shadows, though the highlights hold on to a lot of detail.
Despite a very slight greenish cast, I chose the Auto
white balance setting for the main series. The Daylight
setting was quite warm, and the Manual setting
had a cool, magenta cast.
The Z10 seemed to have a lot of trouble with the exposure on this shot,
not so much an issue of accuracy as it was repeatability. I always bracket
this shot widely to insure I get the best exposure possible. In the case
of the Z10, the exposure varied almost randomly as I advanced from 0 to
+1.3 EV of exposure compensation. (In order, from 0 to +1.3 EV, the shutter
speeds were 1/400, 1/160, 1/200, 1/200, and 1/125.) Hard to figure, given
that the camera was mounted on a tripod, aimed exactly the same for all
the shots, the lighting is entirely continuous, from filtered incandescent
bulbs, and all the shots were captured within 30 seconds of each other.
For whatever reason though, this was the only test shot that I saw this
sort of variation on.
Color-wise, the Z10 seems to oversaturate red and orange hues. As a result,
Marti's skin appears very red here, almost as if she has a sunburn. However,
the blue flowers in the bouquet are nearly right. (Many digicams have
trouble with this blue, often producing strong purplish tints in them,
but accuracy is pretty good here.) Color looks pretty good throughout
the rest of the frame as well, though the red flowers are very oversaturated.
Resolution is very high, and detail is strong in the flower bouquet and
in Marti's features. Shadow detail is moderately high, with low noise.
To view the entire exposure series from zero to +1.3 EV, see files Z10OUTBAP0.HTM
through Z10OUTBAP4.HTM on the thumbnail index page.
Great resolution and detail, slightly high contrast,
oversaturated skin tones.
Exposure and overall color are similar to the wider
shot above, and the Z10's 8x optical zoom lens does a good job of preventing
any geometric distortion of Marti's features. The shot at right was taken
with a +0.7 EV exposure compensation adjustment, which results in hot
highlights on Marti's face but midtones that are about right. Resolution
and detail are stronger in this close-up shot, with excellent definition
in Marti's face and hair. Here again, the biggest problem is the too-pink
skin tone.
To view the entire exposure series from -0.3 to +1.0 EV, see files Z10FACBAM1.HTM
through Z10FACBAP3.HTM on the thumbnail index page.
Slight underexposure at the default setting. Reddish color balance
and a pronounced orange cast in the background.
The Z10's built-in flash had low intensity at the default
exposure, requiring a +0.7 EV exposure compensation
adjustment for a bright shot. Though really, I would have preferred something
in between the +0.7 and +0.3 EV exposures,
as the +0.7 EV shot was a bit too bright. Overall color is reddish, with
an orange cast from the fairly strong incandescent room lighting that
tints the back wall and spills onto Marti's features. Despite the red
and orange casts, the blue flowers in the bouquet don't look too bad,
and have only slight purple tints. I also shot with the camera's Slow-Sync
flash mode, which also required a +0.7 EV
exposure compensation boost, though results are slightly bright here as
well. The orange cast is stronger here, since the longer exposure time
allows more ambient light into the image.
To view the entire exposure series from zero to +1.3 EV in the normal
flash mode, see files Z10INFP0.HTM through Z10INFP4.HTM on the thumbnail
index page.
To view the exposure series from zero to +1.0 EV in the Slow-Sync flash
mode, see files Z10INFSP0.HTM through Z10INFSP3.HTM on the thumbnail
index page.
Good color with all three white balance settings. Higher than average
exposure compensation required.
This shot is always a very tough test of a camera's white balance capability,
given the strong, yellowish color cast of the household incandescent bulbs
used for the lighting, but the Z10 did unusually well with it. The Z10's
Incandescent white balance setting produced the best overall results
here, with just enough of a warm cast to evoke the warmth of the original
lighting, without introducing any strong color shifts. The Auto
setting had a strong red tint, and the Manual
setting was much too cool. Skin tones are still a bit too pink, and the
blue flowers are slightly dark with stronger purple tints in them. Still,
overall color is very good for this difficult light source. The main shot
was taken with a +1.3 EV exposure compensation adjustment, a little higher
than the average required for this subject. The white shirt has a few
hot highlights, but the exposure looks about right elsewhere.
ISO Series:
Noise is generally low in the Z10's images, with very low noise at ISO
64 and acceptable levels at the 100 and 200 settings. Noise becomes more
evident at ISO 400, with a stronger grain pattern, but even there is lower
than I'm accustomed to seeing in the digicams I test.
High resolution and a lot of visible detail, though color casts with
each white balance setting.
Although it had a slight greenish color cast, I chose the Z10's Manual
white balance setting here, as the Auto
setting had a strong red cast and the Daylight
setting a stronger yellow cast. Resolution is high for a three-megapixel
camera, and detail is strong in the tree limbs and leaves above the roof,
as well as in the house front and shrubbery. Corner to corner sharpness
is better than average, with only slight softness in the upper corners
of the frame, and even that not extending very far into the image. A slight
underexposure results in good preservation of highlight detail, but loss
of detail in the shadows. Overall though, a better than average performance.
(Apart from the rather strong color cast in Auto white balance mode.)
High resolution and detail, though slightly limited dynamic range
and a slight underexposure.
This image is shot at infinity to test far-field
lens performance. NOTE that this image cannot be directly compared to
the other "house" shot, which is a poster, shot in the studio.
The rendering of detail in the poster will be very different than in this
shot, and color values (and even the presence or absence of leaves on
the trees!) will vary in this subject as the seasons progress. In general
though, you can evaluate detail in the bricks, shingles and window detail,
and in the tree branches against the sky. Compression artifacts are most
likely to show in the trim along the edge of the roof, in the bricks,
or in the relatively "flat" areas in the windows.
(Note: We'd been having very fickle weather here while we were testing
this camera, and so couldn't manage to capture this shot with the usual
strong sunshine. As a result, this shot isn't as good a test of dynamic
range is it normally would be, but the Z10's difficulty with shadow detail
in it does still speak of limitations in that department. Resolution results
are of course entirely valid though.)
This is my ultimate "resolution shot,"
given the infinite range of detail in a natural scene like this, and the
Z10 does a pretty good job. Detail is strong in the leaf patterns in the
tree limbs above the roof and in the shrubbery in front of the house.
The house front details are also clear and distinct, with good definition
in the brick pattern and windows. All four corners are slightly soft,
but to a much lesser extent than I'm accustomed to seeing in digicam images.
(Minolta's lenses seem to do a better than average job of maintaining
sharpness across the entire frame.) The slight underexposure and hazy
shooting conditions help the camera pick up good detail in the bright
white paint surrounding the bay window, a trouble spot for many digicams.
At the other end of the tonal scale though detail is very limited in the
shadow area over the front door. Overall color looks good, but the image
is as noted somewhat underexposed. The table below shows a standard resolution
and quality series, followed by ISO, sharpness, contrast, and color series.
Sharpness Series: The Z10's in-camera sharpening adjustment offers a good range of control.
The low setting results in images that take unsharp masking in Photoshop
or other imaging programs very well, while the high setting should work
well for images to be printed at small sizes on an inkjet printer. The
default setting is a good balance between the two, providing good sharpening
with few artifacts.
Contrast Series: Like the sharpening control, the Z10's contrast adjustment works well
and provides a useful range of adjustment. Unlike similar controls on
many cameras, the Z10's contrast adjustment affects both ends of the tonal
scale more or less equally, restraining or exaggerating both shadow and
highlight values at the same time.
I routinely shoot this series of images to show the field of view for
each camera, with the lens at full wide angle, at maximum telephoto (8x,
in this case), and at full telephoto with the digital zoom enabled. The
Z10's lens is equivalent to a 36-290mm zoom on a 35mm camera. That corresponds
to a moderate wide angle to a pretty substantial telephoto. Following
are the results at each zoom setting.
Strong color casts with each white balance setting tested, but high
resolution and strong detail.
This shot is often a tough test for digicams, as the abundance of blue
in the composition frequently tricks white balance systems into producing
a warm color balance. The Z10's white balance system had a difficult time
here, producing pronounced color casts with each setting tested. I eventually
chose the Manual setting for the main image,
though it was very cool overall. The Auto and
Daylight settings both produced strong warm casts, with reddish skin
tones. Though skin tones are cool and magenta with the Manual white balance
setting, overall color looks nearer to reality than in the other two images.
The blue background and robe have purplish tints from the magenta cast,
but are close to accurate. The embroidery on the blue robe shows strong
detail, evidence of the Z10's high resolution.
A very small macro area with good detail in the dollar bill.
Flash performs surprisingly well for such close proximity.
The Z10 turned in an excellent performance in the macro category, capturing
a minimum area of only 0.99 x 0.75 inches (25 x 19 millimeters). Resolution
is very high, with strong detail in the dollar bill. (The coins and brooch
are soft due to the very short shooting distance - not the camera's fault.)
As is common with digicam ultra-macro modes, the corners were very soft
though. Also, exposure was low on the right side from the very short shooting
distance, which made it difficult to get enough light onto the subject.
The Z10's flash actually performed surprisingly
well here, considering the very close range. (Still, for ultra
macro shots, plan on using external lighting for the best results.)
Good white balance only with the Manual option, good hue accuracy
but significant oversaturation.
The Z10's Manual white balance setting produced
the best results here, though the image did have a slight greenish cast.
The Auto setting resulted in a strong red
cast, while the Daylight setting produced
a strong yellowish cast. The image is just slightly dark, but the Z10
distinguished the subtle tonal variations of the Q60 target well. Though
slightly cool, the large color blocks have good hue accuracy, but saturation
is a bit too high, particularly in the strong primaries (red, green,
and blue). Shadow detail is a little limited in the charcoal briquettes,
but image noise there is fairly low.
Now, for the REAL technoids, Imatest!
I've recently begun using Norman Koren's excellent "Imatest"
analysis program for quantitative, thoroughly objective analysis of
digicam test images. For those interested, I've prepared a page summarizing
what Imatest showed me about the Z10's images.
The results in the tests below mirror those seen above in other test
shots. The test series are repeated here without further comment, for
the benefit of our more quantitatively-oriented readers.
Good low-light performance, with bright, usable images in almost total
darkness, autofocus and EVF both work down to a bit darker than half typical
city street lighting.
The Z10 produced clear, bright, usable images down to the 1/16 foot-candle
(0.67 lux) limit of my test, at all four ISO settings. Color balance was
reddish with the Auto white balance setting, and the red cast increased
as the light level decreased. At ISO 64, the image was just a little dim
at the lowest light level, but still usable. The Z10's Noise Reduction
system did a good job of controlling bright-pixel noise, and noise levels
were generally lower than average across the board. Although it lacks
an autofocus-assist light, the Z10's autofocus system performed quite
well, focusing accurately down to a light level between 1/2 and 1/4 foot-candle.
This is also the minimum light level that the Z10's viewfinder is usable
at though, which means that the camera can capture images at light levels
much lower than those at which you can aim it effectively. The table below
shows the best exposure I was able to obtain for each of a range of illumination
levels. Images in this table (like all sample photos) are untouched, exactly
as they came from the camera.
(Note: If you'd like to use a light meter to
check light levels for subjects you might be interested in shooting, a
light level of one foot-candle corresponds to a normal exposure of two
seconds at f/2.8 and ISO 100.)
1 fc
11 lux
1/2 fc
5.5 lux
1/4 fc
2.7 lux
1/8 fc
1.3 lux
1/16 fc
0.67 lux
1/16fc
No NR
ISO
64
4 sec
f3.2
8 sec
f3.2
15 sec
f3.2
30 sec
f3.2
30 sec
f3.2
30 sec
f3.2
ISO
100
2.5 sec
f3.2
5 sec
f3.2
10 sec
f3.2
20 sec
f3.2
30 sec
f3.2
30 sec
f3.2
ISO
200
1.3 sec
f3.2
2.5 sec
f3.2
5 sec
f3.2
10 sec
f3.2
20 sec
f3.2
20 sec
f3.2
ISO
400
1/1 sec
f3.2
1.3 sec
f3.2
2.5 sec
f3.2
5 sec
f3.2
10 sec
f3.2
10 sec
f3.2
Flash Range Test
A fairly powerful flash, with consistent results to the maximum test
distance.
In my testing, the Z10's flash illuminated the test target all the way
out to 14 feet, with only a slight decrease in intensity, a better than
average performance, particularly considering that I was shooting at the
camera's minimum ISO setting of 64. Below is the flash range series, with
distances from eight to 14 feet from the target.
Moderately high resolution, 1,000 lines of "strong detail."
High barrel and pincushion distortion.
The Z10 performed slightly below average on the "laboratory"
resolution test chart. It started showing artifacts in the test patterns
at resolutions as low as 500 lines per picture height, in both horizontal
and vertical directions. I found "strong detail" out to around
1,000 lines. "Extinction" of the target patterns occurred around
1,250 lines. The "MTF 50" results
from Imatest show average resolution of 1001 LW/PH uncorrected, or
1265 LW/PH with standard sharpening of radius 1 applied.
Optical distortion on the Z10 is higher than average at the wide-angle
end, where I measured approximately 1.0 percent barrel distortion. The
telephoto end fared only slightly better, as I measured approximately
0.9 percent pincushion distortion. (The pincushion number in particular
is higher than average, as most cameras show quite a bit less pincushion
than barrel.) Chromatic aberration is very low, showing only about two
or three pixels of faint coloration on either side of the target lines.
(This distortion is visible as a very slight colored fringe around the
objects at the edges of the field of view on the resolution target.) The
Z10 also shows better than average sharpness in the corners of the frame,
something I've found to be characteristic of Konica Minolta's long zoom
lenses.
A very accurate electronic optical viewfinder, with good results
from the LCD monitor as well.
The Z10's electronic "optical" viewfinder (EVF) is pretty
accurate, showing about 94 percent frame accuracy at wide angle, and
approximately 99 percent at telephoto. The LCD monitor is also very
accurate, showing about 98 percent frame accuracy at wide angle. However,
the LCD monitor is a little loose at telephoto, as I couldn't measure
my standard lines because they were just outside the frame. Given that
I like LCD monitors to be as close to 100 percent accuracy as possible,
the Z10's LCD monitor and EVF are both excellent. Flash distribution
is fairly even at wide angle, with just a little falloff at the corners
and edges of the frame. At telephoto, flash distribution is more uniform,
though much dimmer.