A limited dynamic range, but good color.

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 Stylus 400 had a little difficulty with the harsh sunlight.

The shot at right was taken with a +1.0 EV exposure compensation adjustment, which still resulted in dark midtones. Highlights are a little bright, but still have good detail. The deep shadows show limited detail, however, with moderate noise. I chose the Daylight white balance setting as the most accurate overall, though color balance is slightly cool with magenta tints.

Skin tones look pretty good, though a little cool, but the blue flowers in the bouquet are darker and more purplish than in real life. (This is a very difficult blue for many digicams to get right. For reference, the flowers are an almost pure light navy blue.) The Stylus 400 also had difficulty with the strong reds in the bouquet, oversaturating them a fair amount. Overall resolution is good, as a lot of fine detail is visible throughout most of the frame.

To view the entire exposure series from zero to +1.0 EV, see files ST40OUTDP0.HTM through ST40OUTDP3.HTM on the thumbnail index page.

Closer Portrait:

Increased resolution and detail, pretty good color.

Results are similar to the wider shot above, in terms of color and exposure. The Stylus 400's 3x zoom lens helps prevent distortion of Marti's features, though a little is still evident. Fine detail is much stronger in this close-up shot, especially in Marti's face and hair. The shot at right was taken with a +0.7 EV exposure compensation adjustment, more compensation than I'm accustomed to using on this shot. Shadow detail is moderate, with a moderate level of noise as well.

To view the entire exposure series from zero to +0.7 EV, see files ST40FACDP0.HTM through ST40FACDP2.HTM on the thumbnail index page.

Indoor Portrait, Flash:

Normal Flash (High Exposure)

Light background and white shirt trick the flash into underexposing. Good coverage and color though.

The light-colored background and Marti's white shirt on this shot often trick cameras' exposure systems in to underexposing the shot. The Stylus Digital 400 fell prey to this problem, and there wasn't any way I could compensate for it, because the exposure compensation adjustment doesn't affect the flash exposure. (Night scene mode combines the flash with a longer shutter time, allowing more ambient light into the shot. This brightens the exposure somewhat, but at the cost of some color mismatch between the flash and room lighting.)

Indoor Portrait, No Flash:

Auto White Balance

Incandescent White Balance

Best color with Incandescent white balance, but still more color cast than I'd like to see.

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 Stylus 400's Incandescent white balance option didn't do too badly, but still left a bit more color cast in the image than I'd personally prefer. (A bit of a judgement call though, as some people might prefer to see more of the original lighting color, to preserve the "mood" of the shot.) The shots at right were taken with +1.0 EV of exposure compensation, about an average amount for this shot.

House Shot:

Auto White Balance

Daylight White Balance

Great color and good detail, but quite a bit of softness in the corners.

The Stylus 400's Auto and Daylight white balance settings produced nearly identical results here, so I chose the Auto setting for the main shot. Resolution is good, as the tree limbs above the roof and fine foliage in front of the house show a fair amount of detail. Trim detail on the house is also good. Details are a bit soft, however, and there's quite a lot of softness along the edges and corners of the left side of the frame (as well as in a significant portion of the top of the frame). There's also a moderate amount of noise throughout the image.

Far-Field Test

Resolution and detail are both good, though dynamic range is slightly limited.

This image is shot at infinity to test far-field lens performance. NOTE that this image cannot be directly compared to the other "house" shot, which is a poster, shot in the studio. The rendering of detail in the poster will be very different than in this shot, and color values (and even the presence or absence of leaves on the trees!) will vary in this subject as the seasons progress. In general though, you can evaluate detail in the bricks, shingles and window detail, and in the tree branches against the sky. Compression artifacts are most likely to show in the trim along the edge of the roof, in the bricks, or in the relatively "flat" areas in the windows.

This is my ultimate "resolution shot," given the infinite range of detail in a natural scene like this, and the Stylus 400 performed fairly well. The tree limbs over the roof and fine foliage in front of the house show a lot of fine detail. Details in the center of the frame are reasonably sharp and well-defined, although the top left corner of the frame is quite soft. The camera picks up good detail in the bright white paint surrounding the bay window, a trouble spot for many digicams, but the shadow area above the front door shows only a small amount of detail, evidence of a slightly limited dynamic range. Color balance is a little cool with the Auto white balance setting, but exposure is about right. The table below shows a standard resolution and quality series.

Resolution Series:

Wide Angle	"Fine" JPEG	"Normal" JPEG
2,272 x 1,704	ST40FARLF	ST40FARLN
2,048 x 1,536	ST40FARMF
640 x 480	ST40FARSF

Lens Zoom Range

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 Stylus 400's lens is equivalent to a 35-105mm zoom on a 35mm camera. That corresponds to a standard wide angle to a moderate telephoto. Following are the results at each zoom setting.

Musicians Poster

Auto White Balance

Daylight White Balance

Good color and 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 Stylus 400's Auto white balance setting fell victim to this trap, and produced a warm, yellow image. The Daylight setting produced a more accurate color balance, though just a hint cool. Still, skin tones look pretty good. The blue robe is a little dark, with slight purple tints in the deep shadows. Resolution is high, with a lot of visible fine detail in the embroidery of the blue robe. Corner softness is again strong in the top left corner of the frame.

Macro Shot

Standard Macro Shot

Macro with Flash

A larger than average macro area, but good detail. Flash works well in macro mode.

The Stylus 400 performed a bit below average in the macro category, capturing a minimum area of 4.74 x 3.56 inches (120 x 90 millimeters). Resolution is high, with good detail in the dollar bill, coins, and brooch. All four corners are soft, the top left more so than the others. Color balance is slightly reddish from the Auto white balance setting, and warm with the flash shot. The Stylus 400's flash throttled down well for the macro area, with only a little falloff in the corners.

"Davebox" Test Target

Auto White Balance

Daylight White Balance

Slight underexposure, excellent color, just slightly warm. Limited shadow detail.

As with the House shot taken earlier, the Stylus 400's Auto and Daylight white balance settings resulted in nearly identical images. Thus, I chose the Auto setting for the main shot. The large white color block and mini-resolution target are slightly warm, but overall color is still very good. Exposure is slightly under, so the camera has no trouble distinguishing the subtle tonal variations of the Q60 target nicely. The large color blocks are a bit dark, but saturation is good. (Though the large red, blue, and magenta blocks are a touch oversaturated.) Detail is limited in the shadow area of the charcoal briquettes, with moderately high noise.

Low-Light Tests

Acceptable low-light capability: Can deliver good shots under typical city street lighting at night.

Its important to use the Digital Stylus 400's Night mode when shooting after dark, as that mode increases the cameras maximum shutter time to four seconds, from the normal 1/2 second limit. In this mode, the camera captured a very acceptable image at a light level of 1/2 foot-candle (5.5 lux). Since average city street lighting at night corresponds to about one foot-candle, the Stylus 400 should do fine with reasonably well-lit night scenes. Color balance was slightly warm with the Auto white balance setting and dim lighting, but noise was surprisingly low. The table below shows the best exposure I was able to obtain for each of a range of illumination levels. Images in this table (like all sample photos) are untouched, exactly as they came from the camera.

Flash Range Test

A little dim at all distances, but only a little falloff at the 14 foot limit of the test. (Higher image noise with increasing distance though.)

Olympus rates the Stylus 400's flash as effective to 8.5 feet (2.5 meters). In my testing, the flash illuminated the test target all the way out to 14 feet, with only a slight decrease in intensity at distances beyond 12 feet. Overall intensity was slightly dim from the eight foot distance on, but intensity remained relatively the same with each additional foot. The ISO information buried in the JPEG file headers reveals the Stylus 400's secret though: It boosts its ISO setting when the flash is in use. This increases the range, but at the expense of significantly increased image noise. Below is the flash range series, with distances from eight to 14 feet from the target.

8 ft	9 ft	10 ft	11 ft	12 ft	13 ft	14 ft
1/100 secs F5.2 ISO: 100	1/100 secs F5.2 ISO: 125	1/100 secs F5.2 ISO: 200	1/100 secs F5.2 ISO: 200	1/100 secs F5.2 ISO: 250	1/100 secs F5.2 ISO: 250	1/100 secs F5.2 ISO: 250

ISO-12233 (WG-18) Resolution Test

Very high resolution for a compact digicam, 1,150 lines of "strong detail." Average barrel distortion at wide angle, no distortion at telephoto.

The Stylus 400 performed very well on the "laboratory" resolution test chart. It started showing artifacts in the test patterns at resolutions as low as 600 lines per picture height horizontally, though not until around 800 lines vertically. I found "strong detail" out to at least 1,150 lines. "Extinction" of the target patterns didn't occur until about 1,400 lines.

Optical distortion on the Stylus 400 is slightly better than average at the wide-angle end, where I measured an approximate 0.7 percent barrel distortion. (While better than average, this is still too high IMHO.) The telephoto end fared much better, as I couldn't find even a pixel of pincushion or barrel distortion. Chromatic aberration was variable, ranging from slight to high depending on the particular corner of the frame I looked in. In most places, it's pretty minor, but the lower right-hand corner showed a good seven or eight 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.) I'm not sure how to rate the distortion, given that it was so variable - I guess I'd call it "average" overall, as in most parts of the frame it was better than average. While it didn't show as much on the resolution target, in other shots, pronounced corner softness was the most visible distortion I noticed testing, strongest in the top left corner of the frame.

Resolution Series, Wide Angle

Wide Angle	"Fine" JPEG	"Normal" JPEG
2,272 x 1,704	ST40RESWLF	ST40RESWMF
2,048 x 1,536	ST40RESWSF
640 x 480	ST40RESWTF

Resolution Test, Telephoto

2,272 x 1,704 (Fine, Tele)

ST40RESTLF