Sony DSC-S750 Exposure

Saturation & Hue Accuracy
Strong color shifts in the cyans, and blues, with oversaturation in reds and blues.

Saturation. The Sony Cyber-shot S750 oversaturates red and blue tones quite a bit, but undersaturates bright yellows. While this is typical of many consumer models, we found the oversaturation a little too much in those areas. 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, with the color balanced properly for the light source, the Cyber-shot S750's skin tones were quite pinkish, more than most consumers would consider natural. 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 Sony Cyber-shot DSC-S750 showed a few severe color shifts relative to the correct mathematical translation of colors in its subjects. For example, cyans were heavily pushed toward blue/violet, and blues toward purple. The result was somewhat unnatural skies, and purplish blues. Reds also took on more of an orange hue. Hue is "what color" the color is.

Exposure and White Balance

Indoors, incandescent lighting
Warm with Auto and Incandescent white balances. About average positive exposure compensation required.

Color balance indoors under incandescent lighting was quite warm with both the Auto and Incandescent white balance settings, but the Incandescent option had the lesser cast. The Cyber-shot DSC-S750 required a +1.0 EV exposure compensation boost to get a good exposure, which is about average for this shot. Overall color is very warm and orange, resulting in a very warm shirt and skin tones, as well as dark, purplish tints in the blue flowers. (Many digital cameras reproduce these flowers with a dark, purplish tint, and the DSC-S750 also struggled here.) 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
Slightly flat color, good exposure, though with high contrast in harsh lighting.

Outdoors, the Sony S750 had some trouble with harsh sunlight, producing very high contrast. Highlights are completely washed-out, with practically no detail, and shadow detail is also limited due to noise artifacts as well as noise suppression. Though the shirt is almost completely blown out in the +0.7 EV portrait shot, this is the closest it gets to good skin tones without excessive highlights taking over the face. Still, contrast is very high, and it would be best to avoid exposures, especially portraits, under conditions like this.

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Resolution
High resolution, 1,400 lines of strong detail.

Our laboratory resolution chart revealed sharp, distinct line patterns down to about 1,400 lines per picture height horizontally and vertically. Extinction didn't really occur, though lines began to merge just a little before 2,000 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
Slightly soft images overall, though still some edge-enhancement on high-contrast subjects. Strong noise suppression limits shadow detail.

Sharpness. The Sony Cyber-shot DSC-S750's images are soft overall, as noise pixels and noise suppression blur the finer details even in bright lighting. Enhancement artifacts are visible on high-contrast subjects such as the crop above left as well. 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 strong noise suppression, with darker (and even not-so-dark) areas of Marti's hair showing blurry, limited detail. Individual strands lose distinction even in the lighter shadows. 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
Moderately high noise at the normal sensitivity setting, with a big jump in noise and very blurry details at the highest settings.

Noise levels and efforts to suppress noise are quite evident even at the Sony Cyber-shot DSC-S750's lower sensitivity settings. At ISO 400, noise is fairly obtrusive, with brightly colored pixels that detract from detail definition, as well as some visible noise suppression. Images at ISOs 800 and 1,250 are really unusable, as noise and noise suppression efforts are so high that the entire image is a blur.

Extremes: Sunlit and low light tests
High contrast with limited highlight and shadow detail under harsh lighting. Limited low-light performance, capable of capturing bright images in near darkness only at the highest sensitivity settings–and with high noise.

Sunlight. The Sony Cyber-shot DSC-S750 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 smudgy detail from noise suppression. The camera required about average compensation to get proper exposure of skin tones, at +0.7 EV, but unfortunately blows the detail in the shirt. Since the DSC-S750 does not offer a contrast adjustment, be sure to use fill flash in situations like the one shown above, or better yet, 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 Sony Cyber-shot DSC-S750 had a little trouble in low-lighting, as it captured bright images at the lowest light level only at the highest sensitivity setting. And results here were marred by noise and noise suppression. At the normal sensitivity settings, images were usable to about one foot-candle, which is about the equivalent of city street lighting at night. Again, image noise is noticeable. The camera's autofocus system was able to focus on the subject only down to a little above the 1/4 foot-candle light level unassisted. (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 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
A modest flash at close range, and fairly dim at full telephoto. Our standard shots required a boost in intensity, though slow-sync results were fine at the default setting.

Coverage. Flash coverage was quite uneven at wide angle, and still a little uneven at full telephoto (where flash power was low). In the Indoor test, the Cyber-shot DSC-S750's flash underexposed our subject a little at its default intensity setting, requiring a boost to High intensity for bright results. The camera's Slow-Sync flash mode produced slightly brighter and more even results at the default intensity, though with a stronger orange cast from the background incandescent lighting.

ISO 100 Range. At wide angle, flash shots at ISO 100 remained fairly bright only out to a distance of about 7 feet, decreasing in brightness from that point on. At full telephoto and ISO 100, the target at 6 feet was already a little dim, with decreasing intensity from there.

Manufacturer Specified Flash Test. In the wide angle shot above, the Cyber-shot DSC-S750 performs about as Sony says it will, producing a fairly good exposure at the rated distance with its ISO set to Auto (which selected ISO 320). At telephoto, the image is slightly dim, and the camera again boosted ISO to compensate (to 200). 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
Mediocre print quality, skewed color, soft 8x10-inch prints. ISO 400 images are soft but usable at 5x7, ISO 800 shots are soft at 4x6.

The Sony S750 turned in some of the poorest printed results we've seen in some time. ISO 100 images were soft at 11x14 inches, and still soft at 8x10, but better. Image quality really only becomes clear at 5x7. This is a very bad start. ISO 200 images are similarly soft at 8x10, but not considerably worse; chroma noise in the shadows and dark areas does become more pronounced, however. ISO 400 images are soft, with coarse chroma noise in the shadows at 8x10, and colors start to face a bit. Chroma noise isn't as noticeable at 5x7, and negligible at 4x6. ISO 800 shots are too smudgy to use at 5x7, but passable at 4x6 inches. ISO 1,250 images are murky, smudgy, and noisy, really not worth the effort.

If all you care to print are full-frame 4x6-inch prints, the Sony S750 will suffice, but there are better cameras on the market in the 7-megapixel range.

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.)