Olympus C-50 Zoom

Nice job, with great resolution and detail, though warm color balance from the Daylight setting.

The extreme tonal range of this image makes it a tough shot for many digicams, which is precisely why I set it up this way, and why I shoot it with no fill flash or reflector to open the shadows. The object is to hold both highlight and shadow detail without producing a "flat" picture with muddy colors, and the C-50 Zoom did a good job.

The shot at right was taken with a +0.7 EV exposure compensation adjustment, though the slightly high contrast results in dark-looking midtones. (Increasing the exposure compensation only blows out the highlights further.) I chose the Daylight white balance for the main series, though color balance is a bit warm and yellow. (The Auto setting produced nearly identical results.) In fairness to the camera though, this shot was snapped a bit later in the day than usual, so the afternoon sun had a warmer cast to it anyway.

Skin tones are a little yellow from the warm cast, and the blue flowers in the bouquet are dark and a little purplish. (This is a very difficult blue for many digicams to get right. For reference, the flowers are a fairly pure light navy blue.) The C-50 also oversaturates the red flowers in the bouquet somewhat, producing a slight halo around the brightest areas that loses detail. Overall though, despite the cast and saturation, I find the color from the C50 very pleasing.

Resolution is very high, with a lot of fine detail visible throughout the frame, but limited detail in the shadows. Details are a touch soft, but definition is still quite good. Image noise is low in the shadows. A good job overall.

To view the entire exposure series from zero to +1.3 EV, see files C50OUTDP0.HTM through C50OUTDP4.HTM on the thumbnail index page.

Closer Portrait:

Excellent resolution and detail.

Overall results are similar to the wider shot above, and the C-50's 3x zoom lens helps prevent distortion of Marti's features. Marti's face and hair show incredible detail, though details are again slightly soft throughout the frame. (This is almost an embarrassing amount of detail, I won't show this to Marti 1:1 on-screen. ;-) The shot at right was taken with +0.3EV of exposure compensation, which loses a little detail in the strongest highlights, but results in a pretty good exposure overall. Shadow detail is moderate, with low noise.

To view the entire exposure series from -0.3 to +0.7 EV, see files C50FACDM1.HTM through C50FACDP2.HTM on the thumbnail index page.

Normal Flash (+0.7 EV)

Slow Sync Flash (+1.0 EV)

Underexposed with the built-in flash at the default exposure, but color is pretty good, and a little positive exposure compensation helps greatly.

The C-50's built-in flash underexposed this subject a fair bit at its exposure setting, requiring an adjustment of +1.0 EV to get a bright exposure. Overall color is pretty good, despite a pink-orange cast on the back wall from the incandescent background lighting, which also spills onto Marti's features slightly. I also shot with the camera's Slow Sync flash mode, which attempts to balance the exposure by allowing more ambient light into the image with a slower shutter speed. Even with an exposure compensation adjustment of +1.0 EV here though, the shot is still rather dark. (Compare to the very dim default exposure.) Still, the longer exposure dispels the pinkish color cast, and produces more even lighting.

To view the entire exposure series with the normal flash mode from zero to +1.3 EV, see files C50INFP0.HTM through C50INFP4.HTM on the thumbnail index page.

Auto White Balance

Incandescent White Balance

Warm color casts with both white balance settings, but exposure is good.

This shot is always a very tough test of a camera's white balance capability, given the strong, yellowish color cast of the household incandescent bulbs used for the lighting.The C-50's Auto and Incandescent settings both had trouble here, producing very warm color casts. I chose the Incandescent image for the main shot, as it had slightly less warmth. Marti's skin tone and white shirt reflect the warm cast, as do the flowers in the bouquet. (The blue flowers are very dark and purplish, though it's probably to be expected, considering the light source.) The shot at right has an exposure compensation adjustment of +1.0 EV. Following are abbreviated exposure series for both white balance settings. (While the +1.3 EV shots show less color, I felt they lost too much detail in the highlights, and looked rather washed out.)

Auto
0.0 EV	+1.0 EV	+1.3 EV

Incandescent
0.0 EV	+1.0 EV	+1.3 EV

ISO Series:
The C-50 shows fairly low image noise at the ISO 80 setting, but levels increase to moderately high at ISO 320.

ISO Series
ISO 80	ISO 160	ISO 320

Auto White Balance

Daylight White Balance

Great resolution and detail, although a warm color cast again.

The C-50's Auto and Daylight white balances both resulted in somewhat warm, yellow casts. Resolution is very high, showing a lot of fine detail in the tree limbs and shrubbery. (In fact, the five-megapixel C-50 is stretching the limits of this poster as a test target.) Details are slightly soft throughout the frame, with increased softness at the corners and vertical edges.

Lens Zoom Range

A typical 3x zoom range.

I routinely shoot this series of images to show the field of view for each camera, with the lens at full wide angle, at maximum telephoto (3x, in this case), and at full telephoto with the digital zoom enabled. The C-50's lens is equivalent to a 38-114mm zoom on a 35mm camera. That corresponds to a moderate wide angle to a medium telephoto. Following are the results at each zoom setting.

Auto White Balance

Daylight White Balance

Good color with the Daylight white balance, with great detail.

This shot is often a tough test for digicams, as the abundance of blue in the composition frequently tricks white balance systems into producing a warm color balance. The C-50's Auto white balance setting fell victim to this trap, producing a reddish image. The Daylight setting did much better, producing pretty accurate colors and skin tones. Even with the slightly cool cast, the blue background has purplish tints that aren't in the original image. The blue robe looks nearly right though, with only very slight purplish tints in the shadow areas. Resolution is very high, with great detail in the embroidery of the blue robe. (This original data file for this poster was only 20MB though, so the C-50 is definitely capable of showing more detail than the poster has in it.)

Standard Macro Shot

Macro with Flash

About average macro performance.

The C-50 turned in about an average performance in the macro category, with a minimum capture area of 3 x 4 inches (76 x 102 mm). The image was slightly soft overall, and lower contrast than I'd have expected, but there was very little softening or distortion in the corners. With the flash enabled, exposure came out quite even, albeit slightly dark, doubtless because the specular reflection from the brooch tricked the flash metering system into underexposing the image. A good but not spectacular job.

Auto White Balance

Daylight White Balance

Good overall exposure and color.

Both the Auto and Daylight settings produced slightly warm images, with the Daylight setting producing the stronger cast. Exposure is pretty good, and the C-50 distinguishes the subtle tonal variations of the Q60 target quite well. The large color blocks are bright and vibrant, with good overall saturation. (The red, green, and blue additive primary colors look just a bit oversaturated to my eye, however.) The shadow area of the charcoal briquettes shows moderate detail, with about the same level of noise. The last steps of both vertical gray scales are also just barely visible. A good job overall.

Low-Light Tests

Great low-light performance, with good color and exposure, but noise is fairly high.

The C-50's adjustable ISO setting, combined with a maximum exposure time of eight seconds, results in good low-light shooting capabilities. The C-50 produced clear, bright, usable images down to the 1/16 foot-candle (0.67 lux) limit of my test at ISO 320, to 1/4 foot-candle at ISO 160, and to 1/2 foot-candle at ISO 80. Color was just a little warm across the board. One thing the C-50 doesn't offer is a noise reduction option, something of a departure for higher-end Olympus cameras. Although there isn't a lot of noise present, the actual noisy pixels are quite bright. Even at ISO 80, several bright pixels dot the image. The Median Filter option in Photoshop(tm) can quickly eliminate the worst of the noise, but for the ultimate treatment, see Mike Chaney's Qimage Pro program. The table below shows the best exposure we were able to obtain for each of a range of illumination levels. Images in this table (like all of our sample photos) are untouched, exactly as they came from the camera.

Flash Range Test

Good flash intensity, all the way to 14 feet.

In my testing, the C-50's flash illuminated the test target all the way out to 14 feet, with only a small decrease in intensity. Below is the flash range series, with distances from eight to 14 feet from the target.

ISO-12233 (WG-18) Resolution Test

High resolution, 1,250 lines of "strong detail." High barrel distortion at wide angle though.

The C-50 performed very well on our "laboratory" resolution test chart. It started showing artifacts in the test patterns at resolutions as low as 800 lines per picture height, in both horizontal and vertical directions. I found "strong detail" out to at least 1,250 lines, "Extinction" of the target patterns didn't occur until about 1,650 lines.

Optical distortion on the C-50 is rather high at the wide-angle end, where I measured approximately 1.05 percent barrel distortion. The telephoto end fared much better, as I found only three pixels of barrel distortion there (about 0.1 percent). Chromatic aberration is moderately high, showing about five or six pixels of coloration on either side of the target lines. (This distortion is visible as a very slight colored fringe around the objects at the edges of the field of view on the resolution target.) With the lens at telephoto, there also seemed to be quite a bit of flare at the boundaries of the dark target elements.

Resolution Series, Wide Angle

Resolution Test, Telephoto

2,560 x 1,920 (Fine, Tele)

C50RESTGF

Sharpness Series