Pentax Optio 330 Digital Camera
|I'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, I'm posting the Thumber index so only those interested in the information need wade through it!|
|Outdoor Portrait: (1516 k)
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 Pentax Optio 330 did pretty well with it. The shot at right has a +0.3 EV exposure compensation adjustment, which brightened up the midtones, although it lost some highlight details in the process. Both the Auto (1509 k) and Daylight (1516 k) white balances resulted in similar images, while Manual (1516 k) white balance produced a greenish image (leading me to choose the Daylight setting). Skin tones look good, and the blue flowers looked pretty good as well, albeit just slightly dark (this is a very difficult blue for many digicams). Details are just a tad soft, but resolution is good overall. The shadows show moderate detail and noise.
|Closer Portrait: (1507 k)
Overall results are similar to the wider shot above, and the 3x zoom lens helps minimize distortion in the model's features, when compared to the results you'd get with the fixed wide-angle lenses on many point & shoot cameras. Fine detail increases in the model's face and hair, and details appear sharper than in the wider shot. The shadow areas show a good level of detail, with moderately low noise. The main shot was taken with a +0.3 EV exposure compensation adjustment.
See files P33FACDP0.HTM and P33FACDP1.HTM on our thumbnail index page for the exposure adjustments of zero and +0.3 EV.
Portrait, Flash: (1147 k)
Good color and balance between the flash and the room lighting.
The Optio 330's flash illuminated the subject well, though overall brightness is just a little low. The strong incandescent background lighting results in an orange cast, but overall color still looks very good.
|Indoor Portrait, No Flash: (1147 k)
Strong color casts in Auto and Incandescent modes, but excellent results with the Manual 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, and the Optio 330's white balance system had a lot of trouble in both auto and incandescent modes. The Incandescent (1128 k) and Auto (1157 k) settings resulted in very warm images, while the Manual (1147 k) setting produced a pretty accurate result. I chose an exposure compensation adjustment of +1.0 EV for the main selection. (Here is a sample image with no exposure compensation (1115 k).) Skin tones are about right, though the blue flowers again are dark and purplish. I also shot sample images at the ISO 100 (1162 k) and ISO 200 (1315 k) settings.
|House Shot: (1507 k)
Good resolution, color, and detail.
Both the Daylight (1506 k) and Auto (1508 k) settings produced warm color casts on this test target, while the Manual (1507 k) setting resulted in a much cooler image. Despite the cool cast, the white value in the Manual setting is more accurate, so I chose it for the main selection. Resolution is moderate, with good detail in the tree limbs above the roof and in the house trim (though details are slightly soft overall). Corner softness is evident in all four corners of the image, but appears strongest on the right side.
(Overall, the Optio 330 seems just slightly soft in most of its photos, at least when compared with the best of the three megapixel field. - I've found most ultra-compact digicams are a bit soft, most likely due to the space constraints on their optics. The 330 shows this to some extent, but its overall image quality is a notch above what I've seen in most other ultra-small cameras.)
|Far-Field Test (1494 k)
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. The Optio 330 captures good detail throughout the frame, actually seeming a bit sharper in this shot than some of my other tests. - Comparing it with normal-sized three megapixel digicams, it actually holds its own on this test quite well, at least in areas of strong contrast. The fine foliage details in front of and above the house show reasonably good definition, like other lower-contrast subject matter (the model's hair in the outdoor portrait shot, for instance), some of the detail is apparently lost to the 330's noise-suppression processing. The bright sunlight causes the 330 to lose most of the detail in the white bay window area, and it also has trouble with the shadow area above the front door, as the brick pattern is only faintly visible. - Overall, dynamic range is a bit limited. The table below shows our standard resolution and quality series, followed by an ISO series.
|Lens Zoom Range
A typical 3x zoom range.
I've received a number of requests from readers to take shots showing the lens focal length range of those cameras with zoom lenses. Thus, I'm happy to present you here with the following series of shots, showing the field of view with the lens at full wide angle, at full 3x telephoto, and at full telephoto with the 2x digital zoom enabled. The Optio 330's lens covers a range equivalent to a 37-111mm zoom on a 35mm film camera. Following are the results at each zoom setting.
Pretty accurate color with good detail.
For this test, I shot with the Auto (1549 k), Daylight (1551 k), and Manual (1510 k) white balance settings, choosing the Daylight setting as the most accurate overall. The Auto setting resulted in too warm of an image, while the Manual setting produced cooler results. Though the Daylight setting appears slightly warm, the skin tones of the models look best. The Oriental model's blue robe looks about right, with only faint purplish tints in the darker areas. (This is a tough blue for many digicams to get right.) Resolution is moderate, with good detail in the embroidery of the blue robe.
Less than average macro area, though good flash performance.
The Optio 330 is a bit below average in the macro category, capturing a rather large minimum area of 5.4 x 4.0 inches (137 x 103 millimeters). Resolution is pretty high, with fairly sharp details in the coins and dollar bill (the brooch is slightly soft, most likely due to the limited depth of field when shooting this close). Color is slightly warm, and the overall exposure a bit dark. Corner softness is again present, but isn't too noticeable. Overall, not bad, but not a first choice if you need to shoot lots of small objects. The 330's flash (1541 k) throttled down pretty well for the macro area, though light falls off at the corners of the frame, and the central area is a bit over-bright.
|"Davebox" Test Target
Good color and saturation, but noise a little high.
I shot samples of this target with the Auto (1210 k), Daylight (1209 k), and Manual (1207 k) white balance settings, noticing the most accurate color balance with the Manual setting. Both Daylight and Auto resulted in warm images, with the Daylight setting producing the warmest color balance of the two. Despite a slight cool cast, the white value of the mini-resolution target is brighter with Manual white balance. Exposure is good, as the Optio 330 picks up subtle pastel tones on the Q60 chart very well, although shadow detail in the briquettes is a bit limited, and image noise is a bit higher than average. The large color blocks are nearly accurate with good saturation.Following are contrast and saturation series.
Excellent performance with good color!
The Optio 330 performed well in the low-light category, as its maximum shutter speed of 15 seconds allows the camera to capture bright images at very low light levels. The camera captured bright, clear images at light levels as low as 1/16 foot-candle (0.67 lux) when shooting at ISO 200, and as low as 1/8 foot-candle (1.34 lux) when shooting at ISO 100. (At ISO 100, the target remains visible at 1/16 foot-candle, but is dim.) The camera's white balance system had some trouble with the low lighting, and produced a pinkish cast in most images. Noise is very low at ISO 100, increasing only mildly at the ISO 200 setting. The table below shows the best exposure I 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
Pentax's stated flash range of 12 feet is accurate.
Pentax rates the Optio 330's flash as effective to 12 feet (3.7 meters) at the wide-angle lens setting and to about 6.6 feet (2.0 meters) with the lens at full telephoto, which matches our findings. In our testing, the 330's flash was brightest at eight feet from the target, becoming progressively darker from that point on as I increased the telephoto lens setting. Flash power was very dim at the 14 foot distance. Below is our flash range series, with distances from eight to 14 feet from the target.
|ISO-12233 (WG-18) Resolution Test (1273 k)
The Optio 330 performed moderately well on our "laboratory" resolution test chart. It started showing artifacts in the test patterns at resolutions as low as 500 lines per picture height, in both horizontal and vertical directions. I found "strong detail" out to at least 950 lines. "Extinction" of the target patterns occurred at about 1,100 lines.
Optical distortion on the 330 is a bit lower than average at the wide-angle end, where I measured an approximate 0.62 percent barrel distortion. The telephoto end fared somewhat better, with about three pixels of barrel distortion there as well. Chromatic aberration is low, showing about two or three pixels of coloration on either side of the target lines, which are exaggerated by the corner softness. (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.)
Resolution Series, Wide Angle
Sharpness Series, Wide Angle
Viewfinder Accuracy/Flash Uniformity
A tight optical viewfinder, though the LCD monitor is very accurate.
The Optio 330's optical viewfinder is a little tight, with about 88 percent frame accuracy at wide angle, and about 84 percent at telephoto. Images framed with the optical viewfinder were also tilted a little toward the lower left corner of the frame. The LCD monitor fared much better, showing approximately 97 percent of the frame at wide angle, and about 99 percent at telephoto. Given that I generally prefer LCD monitors to be as close to 100 percent accuracy as possible, the 330's LCD monitor met my expectations. Flash distribution shows some falloff in the corners of the frame (slightly stronger on the right side of the frame). At telephoto, flash distribution is more even, with a very small amount of falloff in the corners.
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