Olympus 790 SW Exposure

Saturation & Hue Accuracy
Very good overall color and hue accuracy, with minor oversaturation of some colors.

Saturation. The Stylus 790 SW oversaturates strong reds, but actually undersaturates bright yellows, greens, and some blues. Though overall color was fairly pleasing, the bright reds contrasting with the lower saturation greens and yellows was somewhat noticeable. 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, the Olympus 790 SW pushed Caucasian skin tones toward red, resulting in slightly pinkish results. 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 Stylus 790 SW showed moderate color shifts relative to the correct mathematical translation of colors in its subjects, pushing cyan toward blue, red toward orange, and blue toward violet. Hue is "what color" the color is.

Exposure and White Balance

Indoors, incandescent lighting
Very warm color with Auto white balance, though slightly pink results with the Incandescent setting. About average positive exposure compensation required.

Color balance indoors under incandescent lighting was very warm in Auto white balance mode, with a strong orange cast. The Incandescent setting produced more accurate results, though with a reddish cast. The Stylus 790 SW required a +1.0 EV exposure compensation boost to get a good exposure, about average for this shot. Despite the reddish tint with the Incandescent white balance setting, the dark blue flowers in the bouquet have only slight purplish tints. (Many digital cameras reproduce these flowers with a dark, purplish tint, so the Stylus 790 SW performs a little better than average.) 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 exposure, though warm color balance and high contrast. Visible noise suppression limits detail.

Outdoors, the Olympus Stylus 790 SW produced pretty good exposures under bright outdoor lighting, though contrast is high. Shadow detail is limited by strong noise suppression. Overall color balance is fairly warm and reddish with the Auto white balance, and color is a bit dark in the outdoor house shot. Detail definition is low, and noise suppression strong in both images.

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Resolution
High resolution, 1,300 lines of somewhat soft detail.

Our laboratory resolution chart revealed sharp, distinct line patterns down to about 1,300 lines per picture height horizontally and vertically. Extinction occurred around 1,850 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
Somewhat soft images overall, with visible noise suppression that blurs details. Noticeable edge enhancement in high contrast subjects.

Sharpness. The Stylus 790 SW captures soft images, with low detail definition. Noise suppression blurs the finer details even in brighter conditions, but there's only a little evidence of edge enhancement in 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 fairly high noise suppression, with darker areas of Marti's hair showing limited detail. Individual strands become lost in a sea of color. 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.

ISO & Noise Performance
Low to moderate noise at the normal sensitivity settings, with a significant amount of noise suppression. A big jump in noise with strong blurring and desaturation at the higher settings.

The Olympus Stylus 790 SW produced low to moderate noise at the lower sensitivity settings, but the amount of noise suppression applied adversely affects detail definition. Noise suppression is still visible at ISO 400, so detail is lost both to noise and noise suppression. At ISOs 800 and 1,600, noise pixels are very bright and large, smudging detail and altering color, with yellow and purple blotches spreading across the image. See the Output Quality section to see what these items mean when the images are printed.

Extremes: Sunlit and low light tests
Moderately high resolution with good overall detail, but high contrast and limited shadow detail. Limited low-light performance, capable of capturing bright images under normal street lighting only at the higher ISOs.

Sunlight:
The Olympus Stylus 790 SW had some difficulty dealing with the deliberately harsh lighting in the test above, producing very high contrast with washed-out highlights and deep shadows. Shadow detail is limited, with the effects noise suppression quite evident in the form of smudged detail in deep shadow areas. There's also a noticeable amount of distortion in the image, namely chromatic aberration, which almost gives the appearance of shooting through a glass of water. The camera required about average compensation to get proper exposure of skin tones, at +1.0 EV, but the highlights are almost too hot. Be sure to use fill flash in situations like the one shown above; it's better to shoot in the shade when possible.

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 Olympus Stylus 790 SW had trouble in low lighting, and captured bright images only as dark as one foot-candle, and only at ISOs 400 and up. The camera's Night Scene mode performed fairly well, however, capturing brighter images at the lower ISO settings. Noise is somewhat high. Color balance was pretty good, though a hint warm, with the Auto white balance setting. Surprisingly, the camera's autofocus system was able to focus on the subject down to below the 1/16 foot-candle light level unassisted, better performance than its exposure system. (A useful trick is to just prop the camera on a convenient surface, and use its self-timer to release the shutter. This avoids any jiggling from your finger pressing the shutter button, and can work quite well when you don't have a tripod handy.)

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 dSLR camera, but even there, you'll likely need to set the focus manually. For information and reviews on dSLRs, refer to our SLR review index page.

Coverage and Range
Limited flash range, but with moderate coverage. Exposure compensation had no effect on the normal flash mode, but did improve exposure with Slow-Sync flash.

Flash coverage was slightly uneven at wide-angle, but much better than average. At full telephoto, the target was dim but coverage a little more uniform. In the Indoor test, the Stylus 790 SW's flash underexposed our subject just a little at its default setting, but boosting the exposure compensation had no effect. The image is just bright enough for use as is, though still a bit dim. The camera's Slow-Sync flash mode produced slightly brighter and more even results, but with a very strong (some would say unusable) orange cast from the room lighting. Here, the exposure compensation did affect the exposure, and we found the best results with a +1.3 EV boost. Though the exposure is again slightly dim, increasing the compensation to +1.7 EV resulted in strong hot spots.

ISO 100 Range. At wide-angle and ISO 100, the target was reasonably bright out to about 8 feet and decreased in brightness gradually from there. At full telephoto and ISO 100, the target was slightly dim even at 6 feet, and the images darkened gradually from there.

Manufacturer Specified Flash Test. In the wide-angle shot above, the Stylus 790 SW seems to perform almost as Olympus says it will, producing an overexposed image at the rated distance with its ISO set to Auto, though the camera actually selected ISO 800. At telephoto, the camera again boosted ISO to 800 to compensate. Unfortunately, boosting the ISO this high results in a much noisier image, and isn't the ideal performance here. Our standard test method for flash range uses a fixed setting of ISO 100, to provide a fair basis of comparison between cameras. We've now also begun shooting 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
Poor print quality, good color, soft prints at all sizes.

The Olympus Stylus 790SW has delivered the poorest quality printed images we've seen, thanks to a soft lens and heavy noise suppression across the ISO range. Even sharpened at ISO 80, the largest I would recommend that users print its images is 5x7. The rest of the ISO settings just get softer, so they are better kept to 4x6.

Unlike the original Olympus Stylus 720SW, whose images were at least good enough for an 8x10, images from the Stylus 790SW are only passably good at 4x6. We have never had to say this before. Normally printed results prove a camera to be better than it looks onscreen, but the 790SW's images are too soft in both tests.

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 i9900 studio printer, and on the Canon iP5200 here in the office. (See the Canon i9900 review for details on that model.)