Canon PowerShot G1Canon combines dead-easy auto shooting, full manual control, and excellent image quality in a killer3 megapixel!
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PowerShot G1 Sample ImagesReview First Posted: 10/28/2000
|We've begun including links in our reviews to a Thumber-generated index page for our test shots. The
Thumber data includes a host of information on the images, including
shutter speed, ISO setting, compression setting, etc. Rather than clutter
the page below with *all* that detail, we're posting the Thumber index so
only those interested in the information need wade through it!
A very impressive performance! The extreme tonal range of this image makes it a tough shot for many digicams, which is precisely why we set it up this way. The object is to hold highlight and shadow detail without producing a "flat" picture with muddy colors, and the Canon PowerShot G1's white balance system performs well. We shot samples of this image in the automatic (305k), daylight (295k), and manual (303k) white balance modes, choosing the automatic setting for our main series. The manual setting produced very warm results, while the automatic and daylight settings appeared very similar to each other. In the end, we decided that the daylight setting was just a hair cooler than the automatic. Color balance looks great throughout the image, though the blue flowers and pants just a little dark. (These blues are somewhat difficult for many digicams to reproduce correctly, with many digicams shifting the tones towards purple. The G1 shows no tendency toward that problem though, and in fact does a better job with this image overall than most digicams.) Skin tones are very good, saturation is excellent, and the image is overall quite sharp. The shadow areas also show a fair amount of detail, with only a moderate amount of noise. Highlight detail is good, but the brightest parts of the shirt do lose some detail. Our main image was taken with a +0.7 EV exposure adjustment, which did the best job of adequately exposing the shadow areas without blowing out the highlights. The table below shows the results of a range of exposure settings from zero to +1.7 EV in the automatic white balance mode.
Exposure Compensation Settings:
The G1's image contrast adjustments are very effective at altering the contrast level. We noticed that the increased contrast of the Strong setting appeared to give resolution a boost in crispness, due to the heavy definition of light and dark outlines.
We shot with the G1's variable saturation setting, which did a nice job of controlling the color balance while increasing and decreasing the saturation. Adjusting the color saturation to the Strong setting increased the warmth and brightness of this shot, while decreasing saturation seemed to dim the image a little. Overall, a fairly broad range of control, but one that's eminently usable, not going too far in either direction.
The G1 also does a great job with this closer, portrait shot, without much distortion from its 3x lens. (Shorter focal length lenses tend to distort facial features in close-up shots like this and the availability of longer focal lengths is a key feature if you're going to be shooting close-up people shots.) Continuing with the automatic white balance mode, we shot our main image with no exposure compensation adjustment at all. Boosting the exposure compensation to +0.3 EV (1689k) looked only a little brighter than the zero compensation level. (This close-up shot generally requires less exposure compensation than the wider Outdoor Portrait.) Resolution and detail look sharper and crisper than the wider Outdoor shot, especially in the strands of the model's hair, where you can detect the varying shades of blonde. We picked up just a slight moiré pattern in the hair, on those strands reflecting more sunlight. Noise level remains moderate in the shadow areas, and is just noticeable in some of the dimmer highlight areas. The table below shows the results of a range of exposure settings on the G1, from zero to +1.0 EV.
Exposure Compensation Settings:
Portrait, Flash: (1477k)
The G1's built-in flash does a pretty good job of illuminating the subject while maintaining a reasonably accurate color balance throughout the image. We first shot with the G1's internal flash, with no exposure adjustment, which produced this (1411k) very dark image with bluish and purplish hues. Next, we increased the flash exposure compensation to +1.7 EV (1475k), which significantly brightened the image, though the background is still very warm and a slight bluish magenta cast persists in the darker shadow areas (with the exception of the white shirt, which shows very blue shadow areas). We finally boosted the flash exposure compensation level to the maximum setting of +2.0 (1477k), which did a much better job of illuminating the subject. The orangish, warm cast and magenta tints are still present, but the white shirt looks more accurate, as does the model's face and flowers. The end result is quite good, but we're puzzled as to why we had to dial-in so much exposure compensation. (We'd hope for better flash exposure accuracy in the retail units, frankly.) We took advantage of the G1's external flash hot shoe and connected our inexpensive Sunpak flash unit. In the first shot, we bounced the light from the external flash off of the ceiling, producing this (1461k) slightly dim, but more evenly lit shot. A magenta cast is evident throughout the image, but shadows are much softer. Next, we again bounced the flash off the ceiling, but this time held up a sheet of paper in front of it, which had the dual effect of catching some of the light from the flash and diffusing it toward the subject, while simultaneously bouncing a portion of it off the back wall. The result was this (1441k) brighter and very evenly-exposed image. Color balance is slightly better, though the warm, orange cast persists. (Putting an orange gel over the external flash head and using the incandescent white balance setting would have cured this entirely.)
portrait, no flash: (1766k)
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 G1's white balance system had just a bit of trouble with it. We tested the automatic (1751k), manual (1768k), and incandescent (1755k) white balance settings, choosing the manual setting for our main series. Both the automatic and incandescent settings did a reasonably good job of interpreting the lighting, but produced warm casts. While the manual setting still isn't exactly right (there's just a slight magenta cast), the color balance looks the most accurate of the three. Skin tone looks just about right, though a little pinkish. The blue flowers have a purplish tint, but the greens, pinks, and yellows seem about right. In all three white balance settings, we noticed strange, blown-out looking highlights on the model's shirt, particularly around the shoulders. This effect increased dramatically as the exposure compensation increased. For our main shot, we chose a +1.0 EV adjustment, which produced the best level of brightness, albeit rather odd highlights. A moderate noise level is present throughout the image, particularly noticeable in the model's hair and face. We also tested the camera's variable ISO settings, shooting at the 50 (1483k), 200 (1997k) and 400 (2273k) ISO equivalents. We found that as the level of sensitivity increased, the color balance seemed to weaken and noise levels increased. Additionally, the odd highlights on the white shirt seemed to diminish with the different ISO settings, and a strange, bluish color cast appeared at the 400 setting. Noise was fairly acceptable at the ISO 200 setting, but became rather extreme at ISO 400.
Overall, we decided you'll be best off shooting under incandescent
lighting by leaving the exposure compensation set at zero, and then
brightening and color-correcting the resulting images post-exposure.
Here's an example of a default exposure, with a quick "Auto Levels" operation in Photoshop (494k), and a gamma boost of 1.2 applied to it. (Much
better!) The table below shows a range of exposure adjustments from
zero to +1.7 EV using the G1's manual white balance setting.
NOTE that this is the "new" house shot, a much higher-resolution poster than we first used in our tests. To compare the image of the G1 with previously tested cameras, here's a shot of the original house poster in the manual (2883k) white balance setting.
We shot samples of this image with the automatic (482k), cloudy (483k), daylight (479k), fluorescent (480k), and manual (488k) white balance
modes, choosing the manual setting as the most accurate, albeit just a
little cool. The automatic setting produced nice results, though the image
appeared a touch warm. The daylight and cloudy settings both produced warm
results, with the cloudy setting producing the warmest cast. Finally, the
fluorescent setting resulted in a nearly neutral image, but one that had a
very slight magenta cast. Excellent detail is visible in the tree limbs,
shrubbery, and bricks, and the image falls only a hair short of the best
sharpness we've seen in three megapixel cameras. A moderate amount of
noise shows in the roof shingles, as well as in the shadow areas.
In-camera sharpening is just barely perceptible (we just picked up less
than a pixel of the halo effect around the light and dark edges of the
white trim along the roof line). The table below shows the full range of
resolution and quality settings for the G1, all in the manual white
We also shot this test with each of the camera's variable sharpness adjustments. The Strong setting does a nice job of increasing the image sharpness, though we did detect a slight adjustment in contrast. Still, the G1's sharpness adjustment does an excellent job without tinkering with the image brightness level or affecting the contrast too much. The Weak sharpening setting doesn't completely remove the in-camera sharpening, but we did find that strong unsharp masking applied to the Weak image in Photoshop(tm) produced a very crisp image, close to the best we've seen from a 3 megapixel camera.
The G1 also offers an image contrast adjustment, which does a great job of increasing and decreasing the contrast without affecting the brightness level severely. Though the Weak contrast setting does dim the image a little, it manages to maintain a good brightness level.
Color saturation can also be adjusted on the G1, with the same options of Weak, Neutral, and Strong. All three settings perform nicely, increasing or decreasing the tonal saturation just enough.
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.
We shot this image using the automatic (?) white balance mode,
as it produced a very accurate white value, with nice color balance
throughout the image. This shot is a strong test of detail, given the
practically infinite range of fine detail viewable from a distance.
Resolution looks reasonably crisp, though slightly soft, evidenced by the
pine needles and tree branches against the sky, as well as the bricks and
shrubbery. We also judge a camera's dynamic range in this shot, comparing
how well the camera holds detail in both the shadow and highlight areas.
The G1 does a reasonably good job here, though it loses some of the detail
in the bright bay window area, and the outlines of the white paint against
the red brick areas appear a little fuzzy. The dark shadow beneath the
cherry tree on the right side of the house shows a fair amount of detail,
however. A moderate amount of noise is present in the roof shingles, as
well as some of the shadow areas on the house front. We also snapped
images at the 50 (2242k),
100 (2339k), 200 (2531k) and 400 (2839k) ISO settings,
again noticing that as the ISO increased, the contrast seemed to decrease
and the colors flatten a little. Noise also became more pronounced with
the higher sensitivity settings. The table below shows the full resolution
and quality series.
The camera's variable sharpness settings again did a good job of sharpening and softening the image, without affecting the contrast too much. Contrast alters slightly, but not to an extreme level.
The Strong contrast setting managed to heighten the image contrast, while appearing to affect sharpness a little. The Weak contrast setting did the opposite, seeming to soften the edges slightly. The overall changes are of a useful magnitude, although even the Weak contrast setting isn't enough to preserve detail in the very strong highlight in the white paint on the front of the house. Still, a nice, useful range of adjustment.
||Lens Zoom Range
We've received a number of requests from readers to take shots showing the lens focal length range of those cameras with zoom lenses. Thus, we're happy to present you here with the following series of shots, showing the field of view with the lens at full wide angle, the lens at full 3x telephoto and the lens at full telephoto with 4x digital telephoto enabled. We also shot with Canon's wide angle and telephoto lens adapters. We took two shots with the 4x digital telephoto setting, one at the large file size (2048 x 1536) and the other at the small (640 x 480) size, which shows better sharpness because the camera isn't interpolating the image.
Canon appears to have some pretty high-quality optics in their
auxiliary lenses for the G1: While clearly not up to the level of optics
in Canon's high-end professional lenses, they do seem to avoid many of the
pitfalls of auxiliary digicam lenses. The wide angle adapter is quite
sharp, and shows only a little chromatic aberration in the corners.
Likewise, the telephoto adapter is quite sharp, particularly in the
corners of the image, where auxiliary tele adapters frequently have
problems. Overall, a very nice set of optics.
We shot samples of this target using the automatic (385k), daylight (382k), fluorescent (384k), and manual (384k) white balance settings, again choosing the manual setting as the most accurate overall. The daylight setting produced the warmest cast, while the fluorescent setting produced a cooler, slightly magenta image. The automatic setting came close to the right color balance, but had just a hint of warmth. (The significant amount of blue in this image often tricks digicams into overcompensating, so the G1 does an excellent job here.) Color balance with the manual setting looks fairly accurate throughout the image, judging by each of the models' skin tones. The blue of the Oriental model's robe looks nearly accurate, though slightly dark (this is a common problem area for digicams, as it's a hard blue to reproduce correctly). Resolution looks pretty good, with a good bit of detail visible in the bird wings and silver threads on the blue robe. The subtle color gradations on the wings are just barely visible. The flower garland, violin strings, and beaded necklaces also look reasonably sharp. A moderate amount of noise is present in the blue background and shadow areas, and is just perceptible in the faces. Below is our standard resolution and quality series in the G1's manual white balance setting.
We again shot with each of the G1's sharpness adjustments, finding similar results as in our other tests. In this image, we also noticed that the strong setting greatly increases the visibility of the image noise.
Following is a series of images with the G1's contrast adjustments, which again do a nice job of adjusting the contrast without overly affecting the brightness level.
Below are each of the camera's saturation settings, which as before produced nice results, with a useful range of variation.
||Macro Shot (2295k)
The G1 performs well in the macro category, capturing a minimum area of just 3.21 x 2.41 inches (81.64 x 61.23mm). Color balance is a little cool, but detail and resolution both look great. The G1's built-in flash (2304k) does a good job of throttling down for the macro area, tricked ever so slightly by the shiny coin. Color balance appears a little more bluish with the flash, and the large silver coin shows a couple of magenta highlights.
Test Target (1449k)
An excellent performance on this target: We shot samples of this target using the automatic (1017k), daylight (1016k), fluorescent (1016k), and manual (1048k) white balance settings, again choosing the manual setting for our main series. The automatic and daylight settings both resulted in fairly warm images, with the automatic setting showing the warmest cast. The fluorescent setting produced a more accurate white value, but we noticed a very slight magenta cast on the mini-resolution target. Color is accurate and vibrant with the manual white balance setting, and the large cyan, magenta and yellow color blocks look almost perfect, with only a hint of weakness in the difficult yellow swatch. The G1 picks up the difference between the red and magenta color blocks on the middle, horizontal color chart, which is sometimes a problem area for digicams. Exposure looks about right, as the subtle tonal variations of the Q60 chart are completely visible up to the "B" range (another common problem area). The tonal gradations of the vertical gray scales are also distinguishable across their full range: We were just barely able to discern the difference between the last two bars of the black end. The shadow area of the briquettes shows excellent detail, with only a moderate amount of noise, despite how far down the tonal scale that whole area is. We also shot at the 50 (1488k), 100 (1686k), 200 (1991k), and 400 (2436k) ISO settings, noticing that the noise level increased greatly as the sensitivity level increased from 200 to 400. At ISO 50 though, the image is one of the "cleanest" we've seen of this target. Below is our standard resolution and quality series, using the manual white balance setting.
Following is a series of images at each of the G1's sharpness levels. We noticed that the Strong setting brought out more of the detail in the white gauze area, while the Weak setting diminished it somewhat.
In this series, we noticed that the Strong contrast setting made the subtle tonal variations of the black end of the gray scales a little more difficult to distinguish, and it also increased the saturation of the large color blocks ever so slightly.
Here, the Strong setting blurred the difference between the red and magenta color blocks on the horizontal color chart, making the two colors bleed together a little. The large color blocks do brighten significantly with the Strong setting, and appear adequately dim with the Weak setting.
The G1 did an excellent job in the low-light category, as we were able to obtain bright, useable images at light levels as low as 1/16 of a foot candle (0.67 lux). Noise levels stayed relatively low at the ISO 50 and 100 settings, but increased dramatically at the 200 and 400 settings. (We direct readers to Mike Chaney's excellent Qimage Pro program, for a tool with an amazing ability to remove image noise without significantly affecting detail.) Still, we were amazed at the level of brightness we obtained at these low light levels using the 50 ISO setting. The brightness level definitely increased with the higher ISO settings, but the ISO 50 results were still very nice. We also noticed a slightly warm cast to all the images. To put the G1's low light performance into perspective, an average city night scene under modern street lighting corresponds to a light level of about one foot candle. The table below shows the best exposure we were able to obtain for each of a range of illumination levels, at each of the available ISO settings. Images in this table (like all of our sample photos) are untouched, exactly as they came from the camera.
||Flash Range Test
(This test was added in August 1999, so cameras tested before that time
won't have comparison pictures available. As we go forward though, all the
new models will have similar tests available). Canon rates the G1's flash
as effective from 2.3 to 14.8 feet (70cm to 4.5m), which is right in line
with our test results. Though the flash was reasonably effective all the
way out to 14 feet, we noticed a very slight dip in brightness between 10
and 11 feet. Below is our flash range series, with distances from eight to
14 feet from the target.
(WG-18) Resolution Test (393k)
The results of our resolution test supported our conclusions from the other test shots we took with the G1: The camera captures an exceptional amount of detail, easily the equal of any other 3 megapixel camera we've tested, but its images are just slightly soft, compared to the sharpest 3 megapixel cameras we've seen. (Easily corrected post-exposure in an imaging program though.) Numerically, we'd "call" the G1's resolution as about 800 lines per picture height in both vertical and horizontal directions, but there's significant detail visible well beyond that point. At very high spatial frequencies (1100 lines per picture height and above), moderate color artifacts appears, particularly in the horizontal direction. Overall, an excellent performance but, contrary to our usual chiding of manufacturers for using too much sharpening, we'd like to see a little more in the G1's images.
Resolution/Quality series, Wide Angle
Resolution/Quality series, Telephoto
We found the G1's optical viewfinder to be quite a bit loose, showing about 85 percent accuracy at wide angle (276k), and about 82.6 percent at the telephoto (256k) setting. The LCD monitor was much more accurate, showing approximately 96.5 percent of the final image area at wide angle (281k), and about 97 percent at telephoto (246k). (We actually found that the measurements for the LCD monitor differed just slightly with the image size at the telephoto setting, with measurements showing 97.0 percent at 2048, 96.9 percent at 1024, and 96.8 percent at 640.) We generally like to see LCD monitors as close to 100 percent accuracy as possible, so the G1 comes very close to the mark.
Optical distortion on the G1 is fairly low at the wide angle end, as we measured about 0.5 percent barrel distortion at the edges of the frame. The telephoto end fared much better, showing a little under two pixels of pincushion distortion, an almost unmeasureable 0.2 percent. Chromatic aberration is also relatively low, showing only one or two pixels of coloration on each side of the black target lines in the resolution target. (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.) Flash distribution looks uneven at both wide angle and telephoto settings, with a little drop-off at the bottom of the image in both shots. We also noticed an odd color cast throughout the image, with a very magenta tint at the center of the target, slightly bluish tints around the bottom edge, and a greenish cast in the top right corner.