Olympus SP-550 UZ

Color (7.59)
We tested the SP-550UZ to see how accurately it depicted color. We did this by photographing an industry standard color chart manufactured by GretagMacbeth and uploaded the pictures to Imatest imaging software. The program is optimized to the specifications of the color chart. Imatest determines how accurate the colors are and displays the differences between the ideal and those outputted by the camera. Below is a chart produced by Imatest showing the ideal colors in small vertical rectangles, the camera’s colors in the outer squares, and the luminance-corrected ideal colors in the inner squares of each tile.

Imatest outputs another chart that makes seeing these differences even easier. The following chart shows the ideal colors as squares and the camera’s actual colors as circles. The line connecting them represents the degree of error; the shorter, the better.

 

The Olympus SP-550UZ’s colors had a mean color error of 7.9, which is a little below average. This is better than the Olympus SP-500’s 11.5 mean error. The SP-550’s colors were undersaturated by 5.92 percent, which is uncommon among compact digital cameras. Most oversaturate so that colors will look rich and stand out. The SP-550UZ performed decently with an overall color score of 7.59. This is much improved over the awful 5.2 score that the SP-500 received.

White Balance (7.34)
Auto (7.25)
The automatic white balance setting performed averagely. It was very accurate when the flash fired, which is good because there is no preset white balance setting for flash. Under most lighting, there wasn’t much difference between the presets and the automatic setting except under fluorescent and tungsten lighting.

Preset (7.44)
The fluorescent presets were much more accurate than the auto setting under such lights. The tungsten preset was the most inaccurate: it was too blue. Under the same lighting, the auto setting made it appear too red though. Possible solutions include either avoiding tungsten lights or manually setting the white balance.

Fluorescent WB - Fluorscent Illumination

Tungsten WB - Tungsten Illumination

Still Life Sequences
Click on any of the thumbnails below to view the full resolution images.

Still Life Scene
ISO 50	ISO 50
ISO 100	ISO 100
ISO 200	ISO 200
ISO 400	ISO 400
ISO 800	ISO 800
ISO 1600	ISO 1600

Resolution (6.09)
The Olympus SP-550UZ advertises 7.1 megapixels on its 1/2.5-inch CCD. We tested how effective this resolution is by photographing an industry standard resolution chart. After trying several focal lengths and apertures to ensure we got the sharpest shot, we uploaded the dozens of images to Imatest imaging software. The program analyzed the images and chose the sharpest shot, which was taken using an aperture of f/5.0, a focal length of 18mm, and an ISO setting of 50.

Click to view high-resolution image

Imatest outputs resolution results in units of line widths per picture height (lw/ph), which theoretically describes how many alternating black and white lines could fit in the frame. Horizontally, the SP-550UZ can fit 1586 lw/ph with 4.7 percent oversharpening and 1545 lw/ph vertically with 0.21 percent undersharpening. Most digital cameras employ a more aggressive sharpening system, but the results from the Olympus SP-550UZ are ideal.

Still, the Olympus SP-550UZ doesn’t perform as well as some other ultra-zoom digital cameras with the same amount of advertised resolution. The 7.1-megapixel Sony Cyber-shot DSC-H5 resolved 1793 lw/ph horizontally and 1577 lw/ph vertically. Even the 6-megapixel Panasonic Lumix DMC-FZ7 read 1912 lw/ph horizontally and 1497 lw/ph vertically. Granted, the Sony and Panasonic digital cameras did use more in-camera sharpening. The Olympus SP-550’s resolution is good, but it’s not the cream of the crop.

Noise – Auto ISO (2.52)
When tested in bright studio lighting, the Olympus SP-550UZ automatically chose an ISO 125 setting. In this test, many cameras choose the lowest possible ISO setting so the Olympus wasn’t too far off. Unfortunately, there was a lot of noise even at that low setting. The 2.52 overall automatic ISO noise score is disappointing.   

 Noise – Manual ISO (9.3)
The Olympus SP-550UZ performed much better when the ISO is manually set, as most digital cameras do. Below is a chart showing the camera’s ISO settings on the horizontal axis and the associated noise level on the vertical axis.

Most digital cameras steadily increase in noise level as the ISO is bumped up. This isn’t entirely true for the SP-550. The noise peaks at ISO 400 and then decreases at ISO 800 and again at ISO 1600, illustrating the impact of the camera's noise reduction algorithm. The Olympus SP-550’s 9.3 overall manual ISO noise score is quite good.

Low Light (7.75)
Most of our tests are done in the bright lights of a studio, but we switch things up and turn the lights down for this test because that’s how many pictures are taken. We photograph the color chart in light levels of 60, 30, 15, and 5 lux. The first test of 60 lux is similar to a softly lit room with two shaded lamps. The 30 lux test is equivalent to a single 40-watt bulb in an otherwise dark room. The last two tests are extremely dark and aren’t common shooting situations but test the limits of the image sensor if there are any. Below are the images from the tests.

The images maintain illumination, but the colors suffer horribly and noise is obvious. The 60-lux test used a 1-second exposure and oversaturated by 10.6 percent with a mean color error of 17.5 percent. Surprisingly, the colors improved during the 30 lux test with the longer 5-second exposure. The mean color error dropped to 8.7, and the saturation improved to 98.2 percent.

Below is a chart that shows just how much noise is present in each image. Shutter speeds from 1-15 seconds are shown on the horizontal axis. The percentage of the image that is muddled to noise is represented on the vertical axis. The red line shows the amount of noise when the noise reduction system is activated, and the blue line shows what happens when it is deactivated.

Surprisingly, shots taken with the manual noise reduction system engaged actually show more noise in the images. Also surprising is the dip in noise from 1-5 seconds; usually the noise level slopes upward as the exposure time is lengthened. This seems to suggest increasingly aggressive noise reduction as exposure time is prolonged.

Overall, the Olympus SP-550UZ had some surprising results in low light with its ISO 1600 setting. Despite the splotchy look, it received a 7.75 low light score that is much improved over the SP-500’s 6.5 result.

Dynamic Range (5.59)
To see how the camera handles highlights and shadows in an image, we photographed an industry standard dynamic range chart. This chart shows a series of rectangles from light to dark that represent a range of 13 exposure values. The images were uploaded to Imatest software, which determined how much of the range the Olympus SP-550 can show at high and low quality levels. Like our other tests, this is done in a studio with ideal lighting so users shouldn’t expect the same results from everyday shooting. These tests are more valuable for comparison’s sake than anything else.

As expected, the dynamic range diminished as the ISO increased. There is a significant drop from ISO 50 to 200 and then it levels off somewhat to ISO 1600. The message to take away from all this would be to keep the ISO as low as possible especially when shooting outdoors or in bright light. An ISO 50 or 100 setting would be very sensible in order to keep a wide range of tones and a relatively low level of noise in images.

Video Performance (3.48)
Bright Light - 3000 lux
In the bright lights of the studio, the colors in the video weren’t very accurate. The purples and reds were the most erroneous and led to a 12.1 mean color error, as compared to the camera’s 7.9 color error when shooting still images in the same lighting. When snapping pictures, they were a bit undersaturated but videos produced colors that were slightly oversaturated at 108.3 percent. This performance is decent for a digital camera, although there is more noise in the video than most digital cameras have. The Olympus SP-550UZ had an average of 0.625 percent of noise in its videos.

Low Light - 30 lux
With the lights turned low, colors remain fairly true. The mean color error actually dropped from 3000 lux’s 12.1 to 30 lux’s 9.89. More colors seem to be wandering from where they should be, but there isn’t a single color or group within the spectrum that has any particular problems. The saturation is close to perfect at 104.8 percent. Again, colors and saturation fared well here. And again, noise is the only hindrance to a great movie: it jumped to 2.075 percent of the video which is awful.

Video Resolution
Imatest analyzed a video test chart that we recorded and it output resolution results as line widths per picture height (lw/ph) just like the still image resolution results. The SP-550’s 640 x 480-pixel video resolved 357 lw/ph horizontally with 2.9 percent undersharpening and 391 lw/ph vertically with 11.6 percent undersharpening. This is quite good for a digital camera. Its good performance could be credited to the movie mode’s access to exposure and metering adjustments: the better the exposure on the video chart, the more promising the results.

Imatest analyzed a video test chart that we recorded and it output resolution results as line widths per picture height (lw/ph) just like the still image resolution results. The SP-550’s 640 x 480-pixel video resolved 357 lw/ph horizontally with 2.9 percent undersharpening and 391 lw/ph vertically with 11.6 percent undersharpening. This is quite good for a digital camera. Its good performance could be credited to the movie mode’s access to exposure and metering adjustments: the better the exposure on the video chart, the more promising the results.

(100% crops)

Outdoor Motion
Videoing moving subjects outside translated to somewhat jerky video, although nothing worse than any other 30 fps video. The default metering system had trouble when large subjects moved off of the frame: the metering would change drastically and suddenly and then return to what it was. This phenomenon is fairly common but the SP-550’s expression of it is quite exaggerated.

Speed/Timing
Startup to First Shot (6.6)
This digital camera may be shaped like an SLR, but it certainly isn’t as fast as one. It took 3.4 seconds for the Olympus SP-550UZ to start up and snap its first shot.

Shot-to-Shot (9.1)
The 550UZ has five burst modes. The first burst mode takes 3 shots, with 0.9 seconds between each. This 3-shot burst then takes 6 seconds to fully process, but the camera can continue to shoot as it processes. HI1 mode takes 15 shots in 2 seconds, but at decreased resolution (SQ1), and then takes 15 seconds to process. HI2 mode takes 20 shots in 1 second at even lower resolution (SQ2), and takes 10.5 seconds to process. Pre HI2 also takes 20 frames in 0.7 seconds, 5 of which are recorded before the shutter is even pressed. Pre HI2 can also only be shot at SQ2 quality, and takes 10.5 seconds to process. AF mode automatically focuses between each burst shot, taking three shots total, each shot coming 1.4 seconds after the last. This 3-shot burst also takes another 6 seconds to process.

Shutter-to-shot (8.9)
There is some definite shutter lag on the Olympus SP-550, especially when the camera doesn’t have the exposure locked. Once the exposure is locked, it takes less than a tenth of a second to snap the picture. Between the moment users push the shutter release button and the moment the picture is taken, however, 0.9 seconds can go by. The auto focus system prolongs the shutter lag significantly.