Olympus E-520 Image Quality
Olympus E-520 Image Quality
Saturation & Hue Accuracy
Accurate color and saturation, with only minor shifts in hue and intensity.
Saturation. The Olympus E-520 pushes strong blues, reds, and some greens just a little, but actually undersaturates other greens, and cyan tones slightly. Thus, color saturation is a little truer to life than many consumer cameras. 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. In this case, the Olympus E-520 did render skin tones a bit on the pale, pink side in most cases. Still, results are quite reasonable, well within an acceptable range. 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 Olympus E-520 showed only a few small color shifts relative to the correct mathematical translation of colors in its subjects, but had pretty good accuracy overall. Most noticeable was a shift in reds toward orange, and orange toward yellow, with some shifts in cyans and blues as well. Hue is "what color" the
The Olympus E-520 lets you adjust the image saturation, contrast, and sharpness in five steps each. As can be seen below, the saturation adjustment worked moderately well, providing a reasonably fine-grained adjustment over a fairly useful range of control. The saturation adjustment also has almost no impact on contrast. That's how it should work, but we've often found interactions between saturation and contrast (and vice versa) on the cameras we test.
|Saturation Adjustment Examples
The table above shows results with the default as well as lowest and highest available saturation settings. See the Test Shots or Thumbnails index page for more (look for the files named E520OUTSAT0x.JPG). Click on any thumbnail above to see the full-sized image.
| See full set of test images
See thumbnails of all test and gallery images
Exposure and White Balance
Indoors, incandescent lighting
Auto white balance is quite warm, but Incandescent and Manual white balance settings produce good color. Slightly above-average positive exposure compensation required.
|Auto White Balance
|Incandescent White Balance
|Manual White Balance
|2,600 Kelvin White Balance
Indoors, under normal incandescent lighting, the Olympus E-520 produced very warm color with its Auto white balance setting. The Incandescent setting wasn't too far off the mark, but had a slightly warm cast to it. The 2,600 Kelvin option was much too cool, with a blue-green cast. The Manual setting was most accurate, with just a hint of warmth. At +0.7 EV, slightly above average amount of positive exposure compensation was required for this shot (our new indoor portrait scene requires an average of +0.3 EV compensation). Color looks good throughout the frame, with only the slightest purplish tints in the blue flowers. (Many digital cameras reproduce these flowers with a dark, purplish tint, so the E-520 actually performs a little better than average 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.
Good colors overall, though a tendency toward a warm cast and high contrast hurts both highlight and shadow detail. Above average exposure accuracy outdoors.
|Auto White Balance,
|Auto White Balance,
Outdoors, the Olympus E-520 tended to lose highlight detail under harsh lighting while requiring a lower-than-average amount of positive exposure compensation of +0.3 EV. Contrast was quite high, resulting in clipped highlights in mannequin's shirt and some of the flowers, and lost shadow detail in the darker areas. (This reinforces our dynamic range measurements, which showed that the E-520 has less dynamic range than most SLRs currently on the market.) The outdoor house shot has good exposure and natural looking color.
Very high resolution, about 1,600 - 1,700 lines of strong detail.
|Strong detail to
1,700 lines horizontal
|Strong detail to
1,600 lines vertical
Our laboratory resolution chart revealed distinct line patterns down to about 1,700 lines per picture height in the horizontal direction, and about 1,600 in the vertical direction. (Multiply the results from our 2X chart by two.) Extinction occurs around 2,000 and 2,200 lines in both horizontal and vertical directions. 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.
Sharpness & Detail
Pretty good detail, but images are a little soft overall. Some noise suppression visible in the deep shadows.
Sharpness. The Olympus E-520 captured a lot of detail, but its images straight from the camera are slightly soft overall. Even in the high contrast shot above, there's only slight edge enhancement visible along the edges of the house and thicker branches. These images take unsharp masking fairly well, however. 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 some visible noise suppression in the shadows, though quite a bit of fine detail in the strands of hair remains visible. 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, Olympus E-520 JPEGs are pretty detailed, but a little soft. As expected, a bit more detail can be obtained from carefully processing RAW files, without additional sharpening artifacts. 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. Examples include in-camera Super Fine JPEG, RAW file processed through Olympus' Master 2.11 software, and the same file with sharpness increased by 2. Note the similar results at default settings. The fourth crop was processed in Adobe Camera Raw 4.5, using 300% unsharp masking with an 0.3 pixel radius.
ISO & Noise Performance
Low noise at ISO 100 and 200. Noise visible from ISO 400 up, but fine-grained.
The Olympus E-520 produced low noise at its lower sensitivity settings, however we start to see some fine-grained noise at ISO 400. As you'd expect, noise becomes more apparent at ISO 800, but noise is still quite fine-grained and not much detail has been lost to noise reduction. Some chroma noise can be seen in darker, shadow areas. At ISO 1,600, the highest sensitivity supported by the E-520, though noise pixels are quite bright, noise remains fairly fine-grained, and there is still quite a bit of subtle detail to work with. Yellow and magenta chroma noise is more of a problem at ISO 1,600, though, and you can also see some slight horizontal banding in the mannequin's hair. See the Print Quality section to find out what the recommended maximum size print is at each ISO setting.
Extremes: Sunlit and low light tests
High resolution with strong overall detail, though details are slightly soft. High contrast and limited shadow detail, however. Fairly good low-light performance, capable of capturing bright images under average city street lighting, though metering and autofocus struggled at lower light levels.
Sunlight. The Olympus E-520 had a hard time with the deliberately harsh lighting of the above test, producing rather high contrast with washed-out highlights and deep shadows. Though mannequin's face still looks a little dark at +0.3 EV, I preferred that shot to the image at +0.7 EV, which had too many blown highlights for my preference. (In "real life" though, be sure to use fill flash in situations like the one shown above; it's better to shoot in the shade when possible.) 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.)
We really like it when a camera gives us the ability to adjust contrast and saturation. It's even better when those adjustments cover a useful range in steps small enough to allow for precise tweaks. While the Olympus E-520 gives you five settings each for contrast, saturation, and sharpness, we wished it had a little more range on the low side for the contrast adjustment.
|Minimum Contrast, Normal Gradation
|Contrast set to lowest,
|Contrast set to lowest,
At its lowest contrast setting, the E-520 did a fairly good job of preserving highlight detail (some were still blown, hence the desire for more range on the low end of the settings), maintaining natural-looking skin tones, and holding nice detail in the shadows. The E-520 captures good color outdoors, though just slightly on the warm side. Overall, very good results here, especially when the contrast setting is tweaked.
|Contrast Adjustment Examples
The series of shots above shows results with several different contrast adjustment settings, showing the default as well as both extremes. While you can see the extremes, it's hard to really evaluate contrast on small thumbnails like these, click on any thumbnail to go to the full-size image.
One very nice feature of Olympus's contrast adjustment is that it has very little effect on color saturation. Contrast and saturation are actually fairly closely coupled, it's a good trick to be able to vary one without the other changing as well. Olympus did a good job here.
Low light. The Olympus E-520 performed reasonably well on the low-light test, capturing usable, if not bright images at the lowest light level with the lowest sensitivity setting (ISO 100). Images are a little dim at the lower light levels though. This appears to be an issue with the E-520's metering, as one would expect the exposure duration to double for each decrease in light level in the table above, as the aperture is constant. You can always add exposure compensation or use manual mode to get around this limitation. Color balance is just a bit warm from the Auto white balance setting. Noise was low up to ISO 400, but as expected, became more noticeable with higher ISOs. Some slight horizontal banding was evident at higher ISOs as well. There were also a few bright pixels visible at high ISOs and the lowest light level, but that's quite normal. The camera's autofocus system was able to focus on the subject to just below the 1/4 foot-candle light level unassisted (and in complete darkness with the AF assist enabled). Keep in mind that the longer shutter speeds here demand the use of a tripod to prevent any blurring from camera movement. (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.) Digital SLRs like the Olympus E-520 do much better than point & shoots, but you still shouldn't expect a quick autofocus lock with moving subjects.
Good print quality, good color, great 13x19-inch prints. ISO 1,600 images are surprisingly good at 8x10, even better at 5x7.
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 PIXMA Pro9000 review for details on that model.)