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Sample Pictures for the
Sony Cyber-shot DSC-P31 digital camera

(Update Posted 09/05/02)

We've begun including links in our reviews to a Thumber-generated index page for our test shots. The Thumber data includes a host of information on the images, including shutter speed, ISO setting, compression setting, etc. Rather than clutter the page below with *all* that detail, we're posting the Thumber index so only those interested in the information need wade through it!

Outdoor Portrait:

Good color and resolution, with good detail for a two megapixel camera.

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 don't use "fill" flash on it.) The object is to hold highlight and shadow detail without producing a "flat" picture with muddy colors, and the DSC-P31 responded to the challenge very well. The shot at right shows an exposure boost of +0.3 EV, which brought out midtone detail without losing the highlights. (Most cameras require positive compensation on this shot, but the P31 was nearly accurate with its default exposure, though just a little dim.) The Auto (824k) and Daylight (827k) white balance settings produced very similar images, but I chose Auto as the most natural overall. Skin tones look just about right, but slightly pale in the highlights. The blue flowers and pants came out pretty good, with only hints of the purple tint that haunts many digicams on this shot. (This is a difficult blue for many digicams.) Resolution is about what you'd expect for a two megapixel camera. The shadow areas show great detail, with moderate noise. Overall, a very good performance.

To see the entire exposure series, from -0.3 to +1.3 EV, see files P31OUTAM1.HTM through P31OUTAP4.HTM on our thumbnail index page.

 

 

 

Closer Portrait:

Strong distortion from the fixed focal length lens.

Overall results are similar to the wider shot above, though the camera's fixed focal length lens distorts Marti's features. (If you plan on close-in people shots, you should really invest in a camera with an optical zoom lens.) Visible fine detail increases in her face and hair, and details are slightly sharper than in the wider shot. The shadow areas show good detail, with moderately high noise. Color balance is about the same as above, with washed out skin tones in the highlights. The main shot was again taken with a +0.3 EV exposure compensation adjustment.

To view the full exposure series from -0.3 to +0.7 EV, see files P31FACAM1.HTM through P31FACAP2.HTM on our thumbnail index page.

 

 

Indoor Portrait, Flash:

Normal Flash, Normal
Slow Sync Flash, High

Good exposure, with the flash set to "high."

The DSC-P31's flash underexposed this shot a bit, at its Normal (748k) intensity level. Increasing flash intensity to High (721k) brightened the exposure, but left Marti's shirt a little bright. (The Low (729k) setting was much too dim.) The background incandescent lighting results in a yellow-orange cast at the Normal and Low flash settings, which disappears at the High setting. I also shot with the camera's Slow-Sync flash mode, again finding the best results at the High intensity setting. The Normal and Low intensity settings produced dim exposures.

 

 

 

Indoor Portrait, No Flash:

Auto White Balance
Incandescent White Balance
Indoor shooting needs "Twilight Mode," but color is pretty good with Auto white balance.

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 DSC-P31 actually did pretty well here, at least once I figured out that I really had to use the "Twilight" mode to get a long enough shutter time. The camera's Incandescent (778k) setting resulted in a very warm, yellow image, while the Auto (774k) setting also produced a warm image (though with less of a color cast). Even with an exposure adjustment of +1.0 EV, both images are very dark. The main image has a +1.7 EV, which looks about right, but here's a sample image at the default exposure.

To view an abbreviated exposure series from +1.3 through +2.0 EV, see files P31INTWAP4.HTM through P31INTWAP6.HTM on the thumbnail index page.

ISO Series
The P31 has a variable ISO feature, with sensitivity settings extending to ISO 400. I found that these really didn't help a great deal in lower lighting situations, due to the very short shutter speed in "normal" shooting mode, and the fact that the ISO 400 option isn't available in Twilight mode. (Which automatically sets ISO to 200.) Thus, while ISO 400 did help somewhat in this shot, in general, the higher ISO settings will be most useful in brighter settings, for getting a faster shutter speed.

ISO 100

ISO 200

ISO 400

 

 

 

House Shot:

Auto White Balance
Daylight White Balance

Good color, lower than average resolution.

Both the Auto (894 k) and Daylight (855 k) white balance settings resulted in slight warm casts, so I chose the Auto setting for the main image. Color still looks good, but resolution is lower than average for a two megapixel digicam. (Probably no surprise, this is intended to be an entry-level model, not to be compared with high-end two-megapixel cameras.) There's a fair bit of detail there, but the image is rather soft overall.

 

 
 

 

Far-Field Test:

Good color, but a slightly soft image and limited dynamic range.

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 our ultimate "resolution shot," given the infinite range of detail in a natural scene like this. The DSC-P31 captures a fair amount of fine detail throughout the frame, though the details that are there are on the soft side. Given that the P31 is a fixed focal length camera, it's a little hard to compare this shot directly with ones from zoom-equipped models. - To get the house to fill even approximately the same portion of the field of view, I had to get a lot closer, which meant that I was shooting from somewhat below it, hiding many of the fine details in the branches of the trees behind the house from view. The bright sunlight causes the camera to lose practically all detail in the white bay window area, revealing a somewhat limited dynamic range as well. The shadow areas also show limited detail, as the brick pattern above the door is only faintly visible. The table below shows a shortened version of our standard resolution and quality series.

Resolution Series:

Large / Fine
Large / Normal
Medium / Fine
Medium / Normal
Small / Fine
Small / Normal

 

ISO Series:

ISO 100
ISO 200
ISO 400

 

Sharpness Series:

 

 
 

 

Lens Zoom Range

A standard fixed focal length view, "digital zoom" only.

In response to reader requests, I now routinely take these shots, showing each camera's zoom range. In the case of the P31, the only "zoom" is digital, so the image gets quite soft at the highest magnification. The DSC-P31's lens is equivalent to a 33mm lens on a 35mm film camera (a fairly wide angle lens), and the digital zoom extends to 3x. The 3x magnification results in very soft images though, unless you're shooting small images sizes for the web or email. Following are the results at each zoom setting.

 

Wide Angle
Digital Telephoto

 

 
 

 

Musicians Poster
Auto White Balance
Daylight White Balance

Slightly warm color cast with the Daylight setting, but otherwise pleasing color.

Though the Daylight (863k) white balance setting resulted in a slightly warm cast, I chose it over the Auto (857k) setting because of the more pleasing skin tones. The Auto setting appeared nearly accurate, but the skin tones were too warm. The blue robe is about right, though faint purple tints are noticeable in the shadows (this is a tough blue for many digicams to get right). Resolution is moderate, with some detail visible in the embroidery of the blue robe.

 

 

 

Macro Shot
Standard Macro Shot
Macro with Flash

Pretty good macro performance, but the flash has trouble up close.

The DSC-P31 performs about average in the macro category, capturing a minimum area of 4.44 x 3.33 inches (113 x 85 millimeters). Resolution is moderate, with good detail visible on the coins, brooch, and dollar bill. Details are slightly soft, and more so in the corners of the frame. Color looks about right, though a touch warm. I also noticed some barrel distortion from the lens. The DSC-P31's flash (301k) had considerable trouble throttling down for the macro area, overexposing the subject.

 

 

"Davebox" Test Target
Auto White Balance
Daylight White Balance

Very good color, but slightly overexposed.

I chose the Auto (725 k) white balance setting for this shot, as the Daylight (732 k) setting resulted in a very warm image. The DSC-P31 overexposed the target somewhat, losing some details in the white gauze area and in the pastel tones of the Q60 target. Despite being overexposed, the large color blocks look pretty good, hue-wise. However, the red and blue tones appear oversaturated. Some detail is visible in the charcoal briquettes, though with moderately high noise. Following is an ISO series.

 ISO Series
ISO 100
ISO 200
ISO 400

 

 

 

Low-Light Tests

Just sensitive enough for average street lighting at night..

The DSC-P31's maximum shutter time of two seconds limits its low-light shooting capabilities. The camera captured bright, clear images at light levels only as low as one foot-candle (11 lux). The image shot at 1/2 foot-candle (5.5 lux) is almost usable, but a little dim and magenta-colored. The test target remained visible at light levels as low as 1/16 foot-candle (0.67 lux), but shots were too dim for use. Average city street lighting at night corresponds to a level of about one foot-candle, or 11 lux, so the P31 should be just capable of capturing usable images under that lighting. I shot with the camera's Twilight shooting mode, as the Automatic mode only allows 1/30 second as the slowest shutter time. Noise levels are moderately high, with large flecks of color. 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.

1fc
11lux
1/2fc
5.5lux
1/4fc
2.7lux
1/8fc
1.31lux
1/16fc
0.67lux
Click to see P31LL03.JPG

1.6 secs
F2.8

Click to see P31LL04.JPG

2 secs
F2.8

Click to see P31LL05.JPG

2 secs
F2.8

Click to see P31LL06.JPG

2 secs
F2.8

Click to see P31LL07.JPG

2 secs
F2.8

 

 

 

Flash Range Test

Good intensity, remains strong all the way to 14 feet.

The P31's flash maintained a very bright intensity, almost a little too bright, as far as 14 feet from the test target. At eight feet from the test target, flash intensity nearly overpowered the subject. With each additional foot of distance however, brightness decreased just slightly. Below is our flash range series, with distances from eight to 14 feet from the target.

 

8ft. 9ft. 10ft. 11ft. 12ft. 13ft. 14ft.
Click to see P31FL08.JPG

1/ 40 secs
F2.8

Click to see P31FL09.JPG

1/ 40 secs
F2.8

Click to see P31FL10.JPG

1/ 40 secs
F2.8

Click to see P31FL11.JPG

1/ 40 secs
F2.8

Click to see P31FL12.JPG

1/ 40 secs
F2.8

Click to see P31FL13.JPG

1/ 40 secs
F2.8

Click to see P31FL14.JPG

1/ 40 secs
F2.8

 

 

ISO-12233 (WG-18) Resolution Test

Average performance, with strong detail to 800 lines/picture height.

The DSC-P31 turned in a roughly average performance on my "laboratory" resolution test chart. It started showing artifacts in the test patterns at resolutions as low as 500 lines per picture height vertically, but I found "strong detail" out to around 800 lines. "Extinction" of the target patterns occurred at about 1,050 lines.

Optical distortion on the DSC-P31 is lower than most zoom-equipped digicams, but about average for fixed focal length ones. I measured 0.52 percent barrel distortion - More than I'd like to see, but well below the roughly 0.8 percent that's common at the wide angle end of most zoom-equipped cameras' focal length range. Chromatic aberration is fairly low, showing about three or four pixels of very light 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.) The most obvious distortion we noticed was the strong corner softness.

Resolution Series
Large / Fine
Large / Normal
Medium / Fine
Medium / Normal
Small / Fine
Small / Normal

 

Sharpness Series, Wide Angle
Very Low
Low
Normal
High
Very High

 

 

Viewfinder Accuracy/Flash Uniformity

Tight framing with both the optical viewfinder and LCD monitor. Very good flash uniformity though.

The DSC-P31's optical viewfinder was a little tight, measuring approximately 84 percent frame accuracy. The LCD monitor fared only slightly better, showing approximately 91 percent of the frame. Given that I generally prefer LCD monitors to be as close to 100 percent accuracy as possible, I'd say that the DSC-P31 has a little room for improvement here. (On the other hand, there's an argument to be made for having optical and LCD finders match as closely as possible, to avoid confusion when switching between them.) The flash exposure is nice and even, with only slight falloff in the corners of the frame.


Wide Angle - Optical

Wide Angle - LCD

 


Back to the Main DSC-P31 Review

 

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