Sample Images for
Canon PowerShot A40
|For those interested in exposure and file size information, I now include links in my reviews to a Thumber-generated index page for my test shots. The Thumber data includes a range of information on the images, including shutter speed, ISO setting, compression setting, etc. Rather than clutter the page below with *all* that detail, I'm posting the Thumber index so only those interested in the 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. The object is to hold highlight and shadow detail without producing a "flat" picture with muddy colors, and the PowerShot A40 did a good job. The shot at right has a +0.3 EV exposure adjustment, which brightened the midtones while maintaining good highlight detail. The Auto and Daylight white balance settings produced nearly identical results, so I chose the Daylight setting for the main shot. All the colors are nearly perfect, including the blues of the flowers, which have not a hint of the purple tinge that plagues many cameras with this particularly hue (this is a very difficult blue for many digicams). Resolution is high, with great detail throughout the frame. Details are also nice and sharp. The shadow areas have strong detail and very low noise. An excellent performance all around.
To see the full exposure series from zero to +1.0 EV, see files A40OUTDP0.HTM through A40OUTDP3.HTM on the thumbnail index page.
To see the full exposure series from zero to +1.3 EV, see files A40FACP0.HTM through A40FACP4.HTM on the thumbnail index page.
|Indoor Portrait, Flash:
Great intensity, though a pronounced orange cast from the room lighting.
Though a little dim, the A40's flash illuminates the subject well. An orange color cast from the strong incandescent lighting in the room affects the overall color balance, but decreases with increased exposure compensation. I first shot with the flash in its normal setting, at zero and +0.7 EV exposure adjustments. Flash power was low with no exposure compensation, but produced good lighting with the +0.7 EV adjustment. Switching to the Slow Synchro flash mode produced slightly brighter results, as the longer exposure time allowed more ambient light into the image. The longer exposure increases the orange cast slightly as well. I again shot with zero and +0.7 EV exposure adjustments, finding the best results at +0.7 EV.
Portrait, No Flash:
Excellent color balance with Incandescent white balance setting, with good color.
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, and the A40 produced surprisingly accurate color with the Incandescent white balance setting. The Auto setting produced a very warm image with a yellowish, almost sepia color cast. Color looks about right with Incandescent white balance, with a good level of saturation. The blue flowers are dark and purplish, but overall color is excellent. The main image has a +1.0 EV exposure adjustment. Here's an example with no exposure compensation.
Following is an ISO series - Like most compact cameras, the A40's images are pretty good up to about 200 ISO, but really have too much noise at ISO 400 to be usable.
Great resolution and detail, with accurate color.
Both the Auto and Daylight white balance settings produced very similar results in this shot, though the Daylight setting was a hint warm. Color looks good under the Auto setting, with nearly accurate saturation. Resolution is high, with a lot of fine detail in the tree limbs and fine foliage. Details are also pretty sharp (at least for a two megapixel camera). Another very nice performance.
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. The A40 captures a lot of fine detail throughout the frame, with good overall sharpness from corner to corner. Exposure is a little bright, due to the harsh lighting. The A40 loses all but the strongest details in the bright, white bay window area, revealing a limited dynamic range. The shadow area above the front door fares better, as most of the brick pattern is visible. The table below shows our standard resolution and quality series, followed by ISO, Sharpness, and Color series.
|Lens Zoom Range
A standard 3x zoom range.
I've received a number of requests from readers to take shots showing the lens focal length range of those cameras with zoom lenses. Thus, I'm happy to present the following series of shots, showing the field of view with the lens at full wide angle, at 3x telephoto, and at full telephoto with the 2.5x digital zoom enabled. The A40's lens is equivalent to a 35-105mm zoom on a 35mm camera, a pretty typical range for a digicam. Following are the results at each zoom setting.
Nearly accurate color, with high resolution.
The Auto white balance setting produced a very warm color balance, possibly due to the large amount of blue in the composition. Alternatively, the Daylight white balance results in nearly accurate color, with good skin tones on all three models, but looks just slightly cool to my eye. The Oriental model's blue robe looks about right, with only the faintest purple tints in the deep shadows. (This is a tough blue for many digicams to get right, so the A40 does a good job.) Resolution is high, judging by the embroidery details of the blue robe and the well-defined details of the beaded necklaces.
Less than average macro performance.
Well, I guess you can't have absolutely *everything* in a good, low-cost camera: The A40 captured a very large macro area (much like the A30) at 6.6 x 4.9 inches (167 x 125 millimeters). Resolution is high, with great detail in the coins, brooch, and dollar bill. Color looks good, as does overall exposure. The camera's flash throttled down for the macro area, though with a lot of falloff in the corners of the frame.
|"Davebox" Test Target
Great color and saturation, though exposure is a little bright.
On this shot, the Auto and Daylight white balance settings both produced good results. I felt that overall color looked most accurate under the Auto setting, and thus chose it for the main image. The large color blocks look very nice, with nearly accurate saturation. Exposure is a little bright, but the A40 distinguishes the subtle tonal distributions of the Q60 chart well. The shadow area of the charcoal briquettes shows strong detail, with moderately low noise. Following are ISO and Color series.
Excellent low-light capabilities, with very good color.
The A40's Manual exposure mode offers a maximum exposure time of 15 seconds, which gives the camera excellent low-light shooting capabilities. The camera captured bright, clear, usable images at light levels as low as 1/16 foot-candle (0.067 lux) at all four ISO settings (50, 100, 200, and 400 ISO equivalents). Color is accurate, with good saturation. The camera automatically activates a noise reduction system at the longer shutter speeds, which does a good job of controlling noise levels. Still, noise levels were moderately high at the ISO 400 setting. I also noticed that the camera's AF assist light had trouble focusing at times, as some of the lower light level images are a bit soft. The table below shows the best exposure obtained for each of a range of illumination levels. Images in this table (like all of our sample photos) are untouched, exactly as they came from the camera.
|Flash Range Test
Good intensity to 11 feet, dim but usable to 14.
The A40's flash produced fairly good intensity, all the way to 14 feet from the test target. Though the flash power was brightest from eight to 10 feet, it decreased only minimally with each additional foot of distance beyond that point. Overall, I'd probably rate it as having an effective range of about 10-11 feet. Below is our flash range series, with distances from eight to 14 feet from the target.
|ISO-12233 (WG-18) Resolution Test
The A40 performed well on the "laboratory" resolution test chart. It started showing artifacts in the test patterns at resolutions as low as 600 lines per picture height vertically and horizontally. Detail remained strong out to about 750 lines, but artifacts were quite prominent between 600 and 700 lines. "Extinction" of the target patterns occurred at about 1,050 lines.
Optical distortion on the A40 was moderate at the wide-angle end, where I measured approximately 0.59 percent barrel distortion. The telephoto setting fared much better, showing only about two pixels of barrel distortion. Chromatic aberration is very low, showing only about two or three lightly-colored pixels 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.) Overall, this looks like a very good lens.
Resolution Series, Wide Angle
Viewfinder Accuracy/Flash Uniformity
A VERY tight optical viewfinder, but almost 100 percent accuracy with the LCD monitor.
The A40's optical viewfinder was very tight, showing a frame accuracy of only 75 percent at the wide-angle and telephoto lens settings. Images framed with the optical viewfinder were slanted toward the lower left corner, possibly indicating a shifted CCD inside the camera. The LCD monitor fared much better, showing a frame accuracy of approximately 98 percent at wide angle, and about 99 percent at telephoto. Since I like to see LCD monitors as close to 100 percent accuracy as possible, I give the A40 high marks in that area. (But would *really* like to see a more accurate optical finder.) Flash distribution at wide angle is somewhat uneven, with some falloff at the corners of the frame. The telephoto setting shows more even coverage.
Back to the Main PowerShot A40 Review
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