Digital Cameras - Pentax Optio 33WR Test Images
|I've begun including links in our reviews to a Thumber-generated index page for the test shots. The Thumber data includes a host of information on the images, including shutter speed, ISOsetting, compression setting, etc. Rather than clutter the page below with *all*that detail, we're posting the Thumber index so only those interested inthe information need wade through it!|
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 Optio 33WR did a pretty good job.
The shot at right was taken with a +1.0 EV exposure compensation adjustment, about average for this shot. Contrast is on the high side, though midtones aren't too bad overall. I chose the Auto white balance as the most accurate overall (though slightly cool-toned), as the Manual setting was a bit too warm for my tastes, and the Daylight setting appeared warm and greenish.
Marti's skin tone looks pretty good, though a bit more pink than in real life. The blue flowers in the bouquet are almost perfect, just slightly dark. (Many digicams have trouble with this blue, which is in reality a pretty pure, light navy.) The strong reds look about right as well, and saturation is good overall, although the greens seem just a little dull. Resolution is good, with good definition in the fine detail of the bouquet. Detail is strong in the shadows as well, with moderately low noise.
To view the entire exposure series from zero to +1.3 EV, see
files 33WROUTMP0.HTM through 33WROUTMP4.HTM on the thumbnail
Even better detail and resolution, with good color, but once again somewhat high contrast.
I shot this series with the Optio 33WR's Auto white balance setting, but overall color wasn't too different from the wider shot above. The shot at right was taken with a +0.7 EV exposure compensation adjustment, and again has rather high contrast, producing dark midtones and shadows, even though the highlights are blown out. (Boosting the exposure another notch to get better-looking midtones and shadows lost to much detail in the highlights altogether.) The Optio 33WR's 2.8x zoom lens helps prevent distortion of Marti's features, a definite plus in close-up shots like this one. The level of visible fine detail is even higher in this shot, with good definition. Noise is slightly more pronounced in the shadow areas here than in the wider portrait, but is still moderate.
To view the entire exposure series from zero to +1.0 EV, see
files 33WRFACAP0.HTM through 33WRFACAP3.HTM on the thumbnail
Indoor Portrait, Flash:
Good intensity and coverage with the built-in flash, though some exposure compensation required. Better results with Slow-Sync mode.
The Optio 33WR's built-in flash underexposed this shot quite
a bit at the default exposure
setting, requiring a +1.3 EV exposure
compensation adjustment for the best results. Though the overall
exposure is just a little bright, I preferred it to the dull
appearance of the lower exposure settings. Overall color is
pretty good, despite the dim cast. I also shot with the camera's
Slow-Sync flash mode, which required only a +0.7
EV exposure compensation boost. (Here's a shot at the
default exposure, which is just
a little too dim.)
The longer exposure
time allows more ambient light into the image, enabling more
even lighting and more pleasing color (despite a slight blue
cast from the flash itself).
Indoor Portrait, No Flash:
Good color with the Incandescent and Manual white balance settings, about average exposure.
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 Optio 33WR's Auto white balance had a difficult time with this shot, producing a very strong orange cast. Both the Manual and Incandescent settings produced good results though, and I personally preferred the warmer, more natural appearance of the Incandescent setting to the cool tone of the Manual setting. The shot at right was taken with a +1.0 EV exposure compensation setting, which is about average for this subject. Color is good overall, though the blue flowers have a dark, purplish tint (probably to be expected due to the light source).
Slightly cool color, but great detail.
Though slightly cool, I preferred the Optio 33WR's Manual
white balance setting here, as the Auto
setting had too strong of a red cast. (The Daylight
setting was much too yellow.) Resolution is high, and details
are sharp. The tree limbs above the roof, and shrubbery in
front of the house both have great detail. There's a little
softening in the corners, but overall sharpness is still good.
Slightly soft, but good detail, and very little fuzziness in the corners. Good dynamic range as well.
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.
The Optio 33WR turned in a very respectable performance with this target. While slightly soft, its image here shows about the amount of detail I'd expect to see from a three-megapixel camera with this subject. It did a good job of holding detail in the corners, showing relatively little of the corner softness I'm accustomed to seeing in digicam photos. It underexposed the shot slightly, but as a result, did an excellent job of holding onto detail in the strong highlight of the bay window, while at the same time holding good detail in the deep shadow near the door. A good performance overall.
Contrast and Saturation Series:
Lens Zoom Range
A basic 2.8x 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 (2.8x, in this case), and at full telephoto with the digital zoom enabled. The Optio 33WR's lens is equivalent to a 37-104 mm zoom on a 35mm camera. That corresponds to a moderate wide angle to a moderate telephoto. Following are the results at each zoom setting.
Warm color balances, but good detail and resolution.
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 Optio 33WR
had a little trouble here, producing warm color casts at all
three white balance settings. Since the Auto
setting appeared the most natural, I chose it for the main
shot, even though it's still too warm. The Daylight
setting was greenish, and the Manual
setting much too warm. The warm cast gives the blue background
and robe a greenish tint, and the models have ruddy skin tones.
However, resolution is high, with excellent detail in the
embroidery of the blue robe.
A tiny macro area with great detail and good flash performance.
The Optio 33WR performed nicely in the macro category, capturing
a minimum area of only 1.59 x 1.19 inches (40 x 30 millimeters).
Resolution is excellent, as the dollar bill has a lot of visible
fine detail. Detail is also strong in the coins and brooch,
though soft due to the close shooting range. Corner softness
is strong on the left side of the frame, and likely contributes
to the softness on the right side as well. The Optio 33WR's
flash throttled down pretty well
for the macro area, though there is a strong reflection in
the brooch. Overall, an excellent macro performance.
"Davebox" Test Target
Great color with the Manual white balance, although slightly overexposed.
The Optio 33WR's Manual white balance produced very good results here, with an accurate white value in the large color block and mini-resolution target. The Auto was just slightly warm, while the Daylight setting had a strong yellow cast. Exposure is a little bright, but the Optio 33WR still manages to distinguish the subtle tonal variations of the Q60 target. The large color blocks are bright, vibrant, and accurate, with appropriate saturation. Detail is good in the shadow area of the charcoal briquettes, and noise is moderately low.
Somewhat limited low-light performance. Adequate exposures at the lowest light levels, but high image noise. Suitable for typical city scenes at night though.
The Optio 33WR operates under automatic exposure control at all times, but does offer an adjustable ISO setting and maximum shutter time of two seconds in normal exposure modes. (The "Fireworks" scene mode goes to 4 seconds, but there's no metering at all in that mode, so I didn't include it in my tests here.) In my testing, the camera produced, usable images down to the 1/8 foot-candle (1.3 lux) light level at the ISO 400 setting, but the image noise was very high at that level, and image sharpness was severely compromised by the anti-noise processing. As the sensitivity level decreased, so did the minimum light level, such that the ISO 50, shots were only usable at the one foot-candle (11 lux) light level (about the equivalent of average city street lighting at night). Color balance was rather yellow in these shots, so you can expect some color casts in your night shots. Noise was low at the ISO 50 setting, increasing to a high level at ISO 400. 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.
(Note: If you'd like to use a light meter to check light levels for subjects you might be interested in shooting, a light level of 1 foot-candle corresponds to a normal exposure of 2 seconds at F/2.8 and ISO 100.)
Flash Range Test
Good flash range, usable to the 14 foot limit of this test, but the camera boosts its ISO to get there.
In my testing, the Optio 33WR's flash illuminated the test target all the way out to 14 feet, with only a very slight decrease in intensity. That's good news, but it turns out that the 33WR "cheats" a little to get there. Like many digicams these days, the 33WR boosts its ISO setting for distant flash exposures, without informing the user. This does increase the effective range of the flash, but at the cost of significantly higher image noise. Below is the flash range series, with distances from eight to 14 feet from the target.
High resolution, with 1,000 lines of "strong detail." Average barrel distortion, high pincushion though.
The Optio 33WR performed on par for its three-megapixel class on the "laboratory" resolution test chart. It started showing artifacts in the test patterns at resolutions as low as 600-650 lines per picture height, in both horizontal and vertical directions. I found "strong detail" out to at least 1,000 lines, although you could argue for 1,050 lines along the horizontal axis. "Extinction" of the target patterns occurred around 1,300 lines.
Optical distortion on the Optio 33WR is a little less than average at the wide-angle end, where I measured approximately 0.6 percent barrel distortion. The telephoto end did about the same, as I measured a 0.6 percent pincushion distortion. While 0.6 percent is lower than average at the wide angle end, the same amount of pincushion at the telephoto end is higher than average. Chromatic aberration is moderate: While it several pixels of coloration show on either side of the target lines, the coloration is fairly faint. (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
Resolution Test, Telephoto
Viewfinder Accuracy/Flash Uniformity
Excellent accuracy from the LCD monitor, but the optical viewfinder is very tight.
The Optio 33WR's optical viewfinder is very tight, showing only 75 percent of the final frame at wide angle, and about 86 percent at telephoto. This is quite a difference depending on the zoom position, making it difficult to accurately judge just what will be in your photos and what won't. The LCD monitor proved much more accurate, showing about 99 percent frame accuracy at both wide angle and telephoto. Given that I like LCD monitors to be as close to 100 percent accuracy as possible, the Optio 33WR's LCD monitor is essentially perfect in this regard, but I'd really like to see a more accurate optical viewfinder. Flash distribution is a little uneven at wide angle, with some falloff at the corners and edges of the frame. However, at telephoto, flash distribution is more even, though some falloff is still visible in the corners.
33WR Test Images
33WR "Picky Details"
Up to Imaging Resource digital cameras area
Questions, comments or controversy on this article? Click this link to see what other Imaging Resource readers have had to say about Pentax Optio 33WR, or add comments of your own!
Top 3 photos this month win:
1 Canon PIXMA PRO-100
2 Canon PIXMA MG6320
3 Canon PIXMA MG5420