Digital Cameras - Minolta DiMAGE G500 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!|
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 G500 performed fairly well, though with slightly high contrast and saturation.
The shot at right was taken with a +1.3 EV exposure compensation adjustment, quite a bit more than most cameras require for this shot. Contrast is a little high, which results in slightly dark midtones and bright highlights. I shot an image with the camera's low contrast and saturation settings, which helped some, but the effect was relatively slight. (See below for a side-by-side comparison.) I chose the Auto white balance as the most accurate overall, as the Daylight setting was a hint reddish.
Marti's skin tones look pretty good (perhaps just slightly ruddy), and the blue flowers in the bouquet are nearly right. (Many digicams have trouble with this blue, and the G500 does produce slight purplish tints here, but nonetheless does a pretty good job with it.) Color looks good throughout the rest of the frame as well, though the red flowers are just a tad oversaturated. Resolution is excellent, with a lot of fine detail visible throughout the frame. Shadow detail is pretty good, with lower than average noise.
To view the entire exposure series from zero to +1.3 EV, see files G50OUTAP0.HTM
through G50OUTAP4.HTM on the thumbnail
Excellent resolution and detail, but high contrast again.
Overall results are similar to the wider shot above, again with slightly high contrast. Still, midtone detail is good, though detail in the very deep shadows is limited, and Marti's complexion looks a little sunburned here. The shot at right was taken with a +1.0 EV exposure compensation adjustment, again somewhat higher than average for this shot. The G500's 3x zoom lens helps prevent distortion in Marti's features. Detail is outstanding, with sharp details in Marti's face and hair. (Probably more than she would care to see full-screen.)
To view the entire exposure series from -0.3 to +1.0 EV, see files G50FACAM1.HTM
through G50FACAP3.HTM on the thumbnail index page.
Indoor Portrait, Flash:
Good intensity and coverage with the built-in flash, even at its default exposure setting, with good color as well.
The G500's built-in flash illuminated the subject here very well at its
default exposure setting, and produced a bright
exposure with good color. The flower bouquet looks reasonably accurate
for a flash exposure, and there's very little color cast from the background
incandescent lighting. I also shot with the camera's Slow-Sync flash mode,
which surprisingly required a +1.7 EV exposure
compensation boost. (Here's a shot at the default
exposure, which is just a little too dim.)
The longer exposure time allows
more ambient light into the image, which creates a stronger orange cast
from the household lighting. Still, overall color is good, and the exposure
is slightly more even than in the normal flash shot above.
Indoor Portrait, No Flash:
A pink color cast from the Auto white balance setting, and varying exposure results depending on the ISO.
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. The G500's Auto white
balance had just a little trouble here, and produced a pinkish color cast.
The color cast intensified or decreased depending on the ISO and exposure
settings. The main shot was taken at ISO 100, with an exposure compensation
adjustment of +1.0 EV (about average compensation for this shot). Although
the exposure is a little dim, anything brighter produced odd highlights
on Marti's shirt. The pink cast and dim exposure result in purplish tints
in the blue flowers, which are also very dark.
Great resolution and detail, but an overly warm color balance.
Though slightly warm and yellowish, the G500's Daylight
white balance produced the best overall color here, with the most accurate
white value on the house trim. The Auto setting
resulted in a warmer, more yellow color cast. Resolution is very high,
with a lot of fine detail visible in the tree limbs and front shrubbery.
(The G500's five-megapixel CCD stretches the limits of this poster as
a test target. Even though the poster was made from a 500MB scan of a
4x5 negative shot with a tack-sharp lens, the G500 is close to extracting
all the detail that's to be found here.) Details are also sharp throughout
the center of the frame, though corner softness is strong on the left
Excellent resolution and detail, with a good dynamic range and nearly accurate color.
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.
This is my ultimate "resolution shot," given the infinite range of detail in a natural scene like this, and the G500 picks up a lot of fine detail throughout the frame. The tree limbs over the roof and fine foliage in front of the house show strong detail, with excellent definition in the leaf patterns. In-camera sharpening does a good job here as well, and details are sharp across the frame, with very little softening in the corners. The camera picks up pretty good detail in the bright white paint surrounding the bay window as well, a trouble spot for many digicams. Detail is also strong in the shadow area above the front door, but I suspect that the reason the dynamic range looks so good here is that the weather was a little hazy when I shot the image. (One of the difficulties with using outdoor shots for references between cameras.) Overall color looks good, as does exposure. The table below shows a standard resolution and quality series, followed by ISO, sharpness, saturation, contrast, and color series.
Sharpness Series: The G500's sharpness, saturation, and contrast settings all feature adjustment levels from -2 to +2 in arbitrary units. Below is a sampling of images showing the range of those adjustments.
Color Series: The G500 offers a handful of color adjustment options, including the ability to tweak the red, blue, and green channels. Below is a sampling of the adjustments, which span from -2 to +2 in arbitrary units, as well as examples of the camera's Black and White and Sepia options.
Lens Zoom Range
A typical 3x zoom range, biased slightly toward the telephoto end.
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 (3x, in this case), and at full telephoto with the digital zoom enabled. The G500's lens is equivalent to a 39-117mm zoom on a 35mm camera. That corresponds to a moderate wide angle and a good telephoto. Following are the results at each zoom setting.
Reddish color cast in response to the large amount of blue in the composition, but excellent 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. Both the G500's Auto
and Daylight settings were tricked slightly,
producing reddish color casts as a result. As the Daylight setting looked
the most natural to my eye, I chose it for the main image. The reddish
color cast affects the models' skin tones, and produces purplish tints
in the blue background and in the shadow areas of the blue robe. Resolution
is excellent, as the embroidery on the blue robe and red vest show a lot
of fine detail. (The original data file for this poster was only 20MB
though, so cameras like the G500 are definitely capable of showing more
detail than the poster has in it.)
A small macro area with good detail in the dollar bill. Flash is blocked by the lens, however.
The G500 performed pretty well in the macro category, capturing a minimum
area of only 2.85 x 2.14 inches (72 x 54 millimeters). Resolution is very
high, showing a lot of fine detail in the dollar bill. However, the coins
and brooch are soft due to the very short shooting distance (and probably
some corner softness as well). Corner softness is strong on the left side
of the frame. The position of the G500's flash
directly above the lens results in a dark shadow in the lower portion
of the frame, so an external light source will be best for macro shooting.
"Davebox" Test Target
Good overall exposure, but a rather warm color cast.
The G500's Auto and Daylight
settings produced similar, warm-toned images. I chose the Auto setting
for the main shot, though it isn't much different from the Daylight shot.
Exposure is about right, and the G500 distinguishes the subtle tonal variations
of the Q60 target well. Aside from the warm cast, colors are nearly accurate
in the large color blocks, although I found the additive primary colors
(red, green, and blue) a tad oversaturated. (Even the white color block
has a slight halo, along the left side.) The shadow area of the charcoal
briquettes has moderate detail, with moderate noise.
Good low-light performance, with usable images at the lowest light level of my test.
The G500 has a manual exposure mode, adjustable ISO setting, and a maximum exposure time of 15 seconds. As you'd expect then, the camera performed well on my low-light test, capturing bright, usable images down to the 1/16 foot-candle (0.67 lux) limit of my test, at all four ISO settings. (The ISO 50 image is just slightly dim at this lowest light level, but still somewhat usable, and could potentially be brightened with post capture software.) The G500 automatically applies Noise Reduction on exposures longer than 1/2-second. However, I still found noise levels a little higher than I'd like at the ISO 200 and 400 settings, especially with the longer exposures. Color is pretty good overall with the Auto white balance, though the dim lighting results in a reddish cast. 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 my 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 1 foot-candle corresponds to a normal exposure of 2 seconds at F/2.8 and ISO 100.)
Flash Range Test
A moderately powerful flash, with decreasing intensity from nine feet on.
Minolta rates the G500's flash as effective to about 11 feet, a slightly generous estimate in my opinion, but it bears noting that my test shots below were captured at ISO 50, a lower sensitivity than most people would use for after-dark photography. In my testing, the camera's flash illuminated the test target all the way out to 14 feet, but with a gradual decrease in intensity from nine feet on. Below is the flash range series, with distances from eight to 14 feet from the target.
Very high resolution, 1,300-1,350 lines of "strong detail." Slightly high barrel distortion at wide-angle, though low distortion at telephoto.
The G500 performed very well on my "laboratory" resolution test chart. Test patterns in both horizontal and vertical directions looked clean and clear as far as 900 lines, and even the artifacts that did show up were very minor. (Artifacts were strongest in the horizontal test patterns.) I found "strong detail" out to 1,300-1,350 lines, though vertically, you could argue for higher. (I suspect some reviewers would rate the G500's resolution here as high as 1,500 lines or more, but I tend to be a bit more conservative in my resolution ratings than some, feeling that resolution shouldn't be counted past the point where artifacts compete strongly with genuine subject detail.) "Extinction" of the target patterns didn't occur until about 1,700 lines.
Optical distortion on the G500 is slightly high at the wide-angle end, where I measured approximately 0.9 percent barrel distortion. The telephoto end fared much better, as I measured 0.2 percent barrel distortion there. Chromatic aberration looks to be about average, as there's moderately strong coloration visible 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.)
Resolution Series, Wide Angle
Resolution Test, Telephoto
Viewfinder Accuracy/Flash Uniformity
A tight optical viewfinder, but good accuracy from the LCD monitor.
The G500's optical viewfinder is a little tight, showing 83 percent of the final frame at both wide angle and telephoto zoom settings. The LCD monitor proved much more accurate in some respects, showing 98 percent frame accuracy at both zoom settings. However, images framed with the LCD monitor were just slightly cut off at the very left of the frame, so I'd recommend nudging in just a little extra space when tight framing is key. Still, given that I like LCD monitors to be as close to 100 percent accuracy as possible, the G500's LCD monitor performed pretty well here. 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, but dimmer.
G500 Test Images
G500 "Picky Details"
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