Canon G12 Exposure

Saturation & Hue Accuracy
Good saturation levels, with very good hue accuracy overall.

Saturation. The Canon G12 produced good saturation levels, with mild to moderate oversaturation in reds, greens, browns and blues. Some colors such as bright yellow, aqua and cyan were actually undersaturated by a small amount. Overall, the Canon G12's images appeared to fairly vibrant color that wasn't too vivid, and you can always adjust saturation to your liking. Most consumer digital cameras produce color that's more highly saturated (more intense) than found in the original subjects. This is simply because most people like their color a bit brighter than life.

Skin tones. Here, when using Auto white balance, the Canon G12 also did well, producing natural-looking Caucasian skin tones, though just slightly on the cool side, while darker skin tones showed a warmer, yellowish cast. Where oversaturation is most problematic is on Caucasian skin tones, as it's very easy for these "memory colors" to be seen as too bright, too pink, too yellow, etc.

Hue. The Canon PowerShot G12 produced a few color shifts relative to the correct mathematical translation of colors in its subjects, most visibly pushing cyan towards blue (we think for better-looking skies), red toward orange, and yellow toward green. Hue is "what color" the color is.

Exposure and White Balance

Indoors, incandescent lighting
Good color with both Auto and Manual white balance settings. Slightly better than average exposure accuracy.

Color balance indoors under incandescent lighting had a very slight magenta cast with the Auto white balance setting, but was actually quite accurate. The Canon G12 did much better here than the majority of digital cameras we test. The Incandescent white balance option resulted in a fairly strong magenta cast. The Manual setting produced reasonably accurate color, though a touch cool. The PowerShot G12's exposure system handled this lighting well, producing good results with no exposure compensation. (The average for this shot is + 0.3 EV.) Our test lighting for this shot is a mixture of 60 and 100 watt household incandescent bulbs, a pretty yellow light source, but a very common one in typical home settings here in the U.S.

Outdoors, daylight
Good overall performance outdoors, though high contrast and hot highlights. Good color as well.

The Canon PowerShot G12 performed reasonably well under harsh outdoor lighting, though default contrast was quite high. About average exposure compensation (+0.7 EV) was needed to keep the model's facial skin tones bright, resulting in some blown highlights in her shirt and flowers. Overall exposure was pretty good in the outdoor far-field house shot at the default exposure, though some highlights were clipped there as well. Color outdoors is good with the Auto white balance setting, with slightly cool skin tones in the portrait shot. Though contrast is high, the shadows hold onto a fair amount of detail. Fortunately, there's a contrast adjustment to help tame the highlights a bit, though it works better at bringing out shadows.

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Resolution
High resolution, 1,400 to 1,500 lines of strong detail from in-camera JPEGs; about 1,700 from RAW files.

Our laboratory resolution chart revealed sharp, distinct line patterns down to about 1,500 lines per picture height in the horizontal direction, and about 1,400 lines per picture height in the vertical direction. (Some might argue for over 1,800 lines, but artifacts such as moire begin to appear at much lower resolutions.) Extinction of the pattern occurred between 2,200 and 2,400 lines. Adobe Camera RAW was able to extract more resolution with fewer artifacts from the G12's .CR2 RAW files, about 1,700 lines, and complete extinction of the pattern was extended to between 2,600 and 2,700 lines. Use these numbers to compare with other cameras of similar resolution, or use them to see just what higher resolution can mean in terms of potential detail.

See full set of test images with explanations
See thumbnails of all test and gallery images

Sharpness & Detail
Sharp, detailed images overall, with only minor edge-enhancement on high-contrast subjects. Noise suppression limits definition in low contrast areas, though better than average results here.

Sharpness. The Canon PowerShot G12 captures very good detail and fairly sharp JPEG images at default settings. Only slight enhancement artifacts are visible on high-contrast subjects such as the crop above left. Edge enhancement creates the illusion of sharpness by enhancing colors and tones right at the edge of a rapid transition in color or tone.

Detail. The crop above right shows moderate levels of noise suppression, as the low contrast areas of hair show less distinct detail. However, many individual strands remain fairly well defined, so performance here is actually better than average for a compact digicam. Noise-suppression systems in digital cameras tend to flatten-out detail in areas of subtle contrast. The effects can often be seen in shots of human hair, where the individual strands are lost and an almost "watercolor" look appears.

RAW vs In-Camera JPEGs
As noted above, the Canon G12 produces fairly sharp, detailed in-camera JPEGs. More detail is often available from RAW files, but the amount of noise present in images from these small sensors means noise reduction must be fairly sophisticated to extract additional detail without making noise an issue. In the image below, processing from RAW using Canon's bundled software brought no real improvement in visible detail, though Adobe Camera RAW did better at the expense of more visible noise. Take a look below, to see what we mean:

In the table above, mousing over a link at the bottom will load the corresponding crop in the area above, and clicking twice will open the full resolution image.

The image on the left is an in-camera Fine JPEG taken with default settings. The image in the center is a RAW file processed using Canon's included Digital Photo Professional software, using default settings. The image on the right is the same RAW file processed in Adobe Camera RAW, then sharpened in Photoshop using strong but tight Unsharp Mask (USM) of 500% with radius of 0.3 pixels.  As you can see, Canon's Digital Photo Professional software wasn't really able to extract more detail than the in-camera JPEG, and it shows a few more sharpening artifacts. The ACR converted .CR2 does reveal more detail, but also shows more noise. The G12's JPEG engine is doing a pretty good job trading off detail versus noise, but for full control over detail, noise and sharpening (as well as contrast and saturation), shoot RAW and use a good RAW converter.

ISO & Noise Performance
Low noise at the normal sensitivity settings, with pretty good results up to ISO 400. Strong noise and loss of detail at higher settings, however.

The Canon G12's high ISO noise performance is very similar to that of the G11's, though it seems to do a bit better at retaining fine detail at higher ISOs. The Canon PowerShot G12 produced low to moderate noise at the lower sensitivity settings, but the effects of noise reduction such as smudging and loss of fine detail can already be seen even at the lowest ISO. Fine detail holds pretty strong up to ISO 200, though. At ISO 400, noise is still reasonable and a lot of fine detail remains intact, but additional smudging is evident. Noise grain isn't really more apparent as you move to ISO 800, but stronger noise reduction results in additional detail loss. Yellow and purple blotches (chroma noise) begin to appear in darker tones and hair at ISO 800, and worsen as ISO goes up. At ISOs 1,600 and 3,200, artifacts from noise reduction and increased chroma noise dominate, blurring out most fine detail. Still, overall handling of detail versus noise is better than the typical compact camera. On-screen crops like this tell you only part of the story with a camera, though: To see how these images held up when printing at various sizes, read the Output Quality section below.

Extremes: Sunlit and low light tests
High resolution with strong detail, though somewhat high default contrast limits dynamic range. Good low-light performance, capable of getting bright images in near darkness.

Sunlight. The Canon PowerShot G12 performed reasonably well under the deliberately harsh lighting in the test above, but with washed-out highlights and some deep shadows. Despite some noise suppression in the shadow areas, detail is still good in the shadows. At +0.3 EV exposure compensation, the face, background and some shadow areas are a little dark, so we preferred the +0.7 EV exposure, though it resulted in some blown highlights in her shirt and flowers. Some may prefer the +1.0 EV setting as the model's face is brighter, but we felt it had too many clipped highlights. The PowerShot G12 offers five contrast levels settings, but as mentioned previously they work better lightening shadows than reducing clipped highlights, so be sure to adjust your exposure accordingly. Also consider using fill flash in situations like the one shown above; and it's better to shoot in the shade when possible.

As part of the G12's Intelligent Contrast (i-Contrast) feature, the camera has "Dynamic Range Correction" to tame highlights, and "Shadow Correct" to bring out more shadow detail. A separate "High Dynamic Range" mode takes three shots at different exposures and combines them in-camera, but does not micro-align them like some other cameras, so a tripod is required.

Above are examples of our "Sunlit" Portrait scene shot with the G12's i-Contrast Dynamic Range Correction feature. These shots were taken with +0.7 EV compensation because the default exposure was a little dim with few blown highlights. As you can see, higher DR Correction settings have better highlight retention than lower ones. The DR Auto setting did a pretty good job, with similar but not identical results compared to DR 200%. Note that Dynamic Range Correction boosts ISO, so more noise can be visible with it enabled. (DR Auto used ISO 125, ISO DR 200% used ISO 160 and DR 400% used ISO 320 for these shots. ISO was set to Auto, and the DR Off case used ISO 80. )

The table above shows results with the default exposure using Aperture Priority AE, as well as Smart Auto and Portrait scene modes. As you can see, the G12's face detection in both Smart Auto and Portrait modes improved exposure automatically compared to the default exposure in Aperture Priority mode. We much preferred the Smart Auto image, as the camera also applied some Intelligent Contrast resulting in far fewer blown highlights, though Portrait mode seemed to turn down the sharpening for a softer effect. Both modes boosted ISO from 80 to 320.

Because digital cameras are more like slide film than negative film (in that they tend to have a more limited tonal range), we test them in the harshest situations to see how they handle scenes with bright highlights and dark shadows, as well as what kind of sensitivity they have in low light. The shot above is designed to mimic the very harsh, contrasty effect of direct noonday sunlight, a very tough challenge for most digital cameras. (You can read details of this test here.)

Low light. The Canon PowerShot G12 did very well in our low-light tests, capturing bright, usable images at sensitivities as low as ISO 80. Given that the G12 is capable of shutter speeds as slow as 15 seconds, the camera should have no problems capturing usable images at much lower light levels than the one foot-candle level we tested at. Noise is very well controlled to ISO 800, and color balance looks good if slightly cool with the Auto white balance setting. The Canon G12's Low Light mode (as indicated by the candle icon on the mode dial) reduces resolution to 2.5-megapixels by pixel-binning, producing lower noise and allowing higher ISOs up to 12,800. The camera's AF system was able to focus unassisted down to the 1/16 foot-candle light level and in complete darkness with the AF assist lamp, keeping up well with its exposure system.

How bright is this? The one foot-candle light level that this test begins at roughly corresponds to the brightness of typical city street-lighting at night. Cameras performing well at that level should be able to snap good-looking photos of street-lit scenes.

NOTE: This low light test is conducted with a stationary subject, and the camera mounted on a sturdy tripod. Most digital cameras will fail miserably when faced with a moving subject in dim lighting. (For example, a child's ballet recital or a holiday pageant in a gymnasium.) For such applications, you may have better luck with a digital SLR camera, but even there, you'll likely need to set the focus manually. For information and reviews on digital SLRs, refer to our SLR review index page.

Coverage and Range
Good flash power for its size, with uneven coverage at wide-angle. Good exposure from Auto flash mode in our indoor portrait test shot.

Coverage and Exposure. Flash coverage was uneven at wide-angle, with more uniform (albeit very dim) results at full telephoto. The G12's Auto flash mode did a good job with our indoor flash portrait test, resulting in a bright image at ISO 250 (automatically selected). The G12 used a fairly slow shutter speed of 1/25 second however, which could lead to some issues with subject motion blur.

ISO 100 Range. At wide-angle and ISO 100, flash shots were bright to about 13 feet, decreasing in brightness from that point on. At the telephoto end, flash shots started out bright at 6 feet, but brightness began to fall off after 7 feet.

Manufacturer Specified Flash Test. Canon rates the PowerShot G12's flash range at 7 meters / 23 feet at wide-angle and 4 meters / 13 feet at telephoto, when using Auto ISO. In the shots above, the PowerShot G12's flash performs to Canon's specifications, producing bright images at both wide-angle and full telephoto, though the camera boosted ISO to 400 and 320 respectively.

Our standard test method for flash range uses a fixed setting of ISO 100, to provide a fair basis of comparison between cameras. We now also shoot two shots using the manufacturer-specified camera settings, at the range the company claims for the camera, to assess the validity of the specific claims.

Print Quality
Good print quality, good color, sharp 16 x 20-inch prints. ISO 400 images are good at 11 x 14, ISO 800 shots are good at 8x10, and even ISO 3,200 shots are good at 4 x 6.

ISO 80 and 100 shots look good at 16 x 20 inches, if just a bit soft in our red leaf swatch.

ISO 200 images have good detail at 13 x 19 inches, with only minor luminance noise in the shadows.

ISO 400 shots are good at 11 x 14, again showing only minor grain in the shadows.

ISO 800 images are good at 8 x 10, and 11 x 14s may be usable in less critical applications.

ISO 1,600 shots look better at 5 x 7, with the only exception being the loss of all contrast in our target red swatch.

ISO 3,200 shots are quite good at 4 x 6.

Overall, a very good performance from the Canon G12. Dark areas deepen slightly as we move up the ISO ladder and down in print size, but color and apparent exposure look pretty consistent. It's also a little better image quality than we saw in the Canon S95.

Testing hundreds of digital cameras, we've found that you can only tell just so much about a camera's image quality by viewing its images on-screen. Ultimately, there's no substitute for printing a lot of images and examining them closely. For this reason, we now routinely print sample images from the cameras we test on our Canon Pro9000 Mark II studio printer, and on the Canon Pixma MP610 here in the office. (See the Canon Pixma Pro9000 Mark II review for details on that model.)