Digital Cameras - Pentax Optio 33L 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, 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: |
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 33L had a little trouble with it.
The shot at right was taken with a +0.7 EV exposure compensation adjustment, which produced good midtones, but really blew out the highlights on Marti's shirt. This, even though I had the 33L's contrast adjustment set to its low setting. I chose the Daylight white balance as the most accurate overall, as the Auto setting was cool, and the Manual setting was warm and greenish.
Skin tones are nearly accurate, although a little dark in this shot, and the blue flowers in the bouquet are quite dark and purplish. (This is a very difficult blue for many digicams to get right. For reference, the flowers are a light navy blue with just a tinge of purple to the naked eye.) The bright red flowers are slightly oversaturated, but the camera holds onto a fair amount of detail in the hottest spots. Resolution is high, with good detail in the bouquet, as well as in Marti's features. Detail is also good in the shadows, with moderately low noise.
To view the entire exposure series from zero to +1.3 EV, see files O33LOUTLCDP0.HTM through O33LOUTLCDP4.HTM on the thumbnail index page.
Increased resolution and detail, but trouble again with contrast.
Like the wider shot above, contrast was high again here, so I once more shot with the camera's Low contrast setting. Though the overall exposure is slightly dim, the highlights still lose a fair amount of detail. The shot at right was taken at the default exposure setting, as anything brighter blew out the highlights even more. Resolution is much higher in this shot, with stronger detail in Marti's face and hair. Detail is also good in the shadows, with moderately low noise. Additionally, the Optio 33L's 3x zoom lens helps prevent distortion of Marti's features.
To view the entire exposure series from -0.3 to +1.0 EV, see files O33LFACLCDM1.HTM through O33LFACLCDP3.HTM on the thumbnail index page.
Good intensity and coverage with the built-in flash and a positive exposure boost, with nearly accurate color.
The Optio 33L's built-in flash illuminates the subject well, with a +1.0 EV exposure compensation adjustment. (The default setting was quite dim.) The +1.0 EV adjustment is just a little bright, creating very bright highlights on Marti's shirt, but the image at +0.7 EV was just a little too dark for my liking. The back wall has a slight magenta cast caused by the background household incandescent lighting, but overall color is pretty good throughout the frame. The red flowers have high saturation, which blurs detail slightly.
To view the entire exposure series from zero to +1.3 EV, see files O33LINFP0.HTM through O33LINFP4.HTM on the thumbnail index page.
Good color with the Manual white balance, though the Incandescent setting produces an acceptable image too. Higher than average exposure compensation required though.
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 33L's Auto white balance had a lot of trouble here, producing a very strong warm cast. The Manual option produced the best overall color, though the Incandescent setting was close to accurate too (just a little warm and yellow-green). I achieved the best exposure with a +1.3 EV exposure compensation adjustment, a bit more than the +1.0 EV that most cameras require on this shot.
Great resolution, detail, and color, but a slight underexposure.
The Optio 33L's Auto white balance setting produced the most accurate results here, and produced a good white value on the house trim, as well as a good overall color balance. That said, both the Manual and Daylight settings weren't too far off the mark, with just slight color casts each. Resolution is high, showing a lot of detail in the tree limbs and shrubbery. Details are sharp throughout the frame, but there's quite a bit of softness in the corners, along both sides of the frame. The images are slightly underexposed, but results are good overall.
Very good resolution and detail and excellent color, but a slightly 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 my ultimate "resolution shot," given the infinite range of detail in a natural scene like this, and the Optio 33L turns in a nice performance. Detail is strong in the tree limbs over the roof and fine foliage in front of the house, as well as in the more linear details of the house itself. Details are fairly sharp throughout the frame, although there's once again noticeable softness in the corners along the left side. The camera picks up only the strongest details in the bright white paint surrounding the bay window, tricked slightly by the bright sunlight. Detail is a little stronger in the shadow area above the front door, but it's clear that the 33L's dynamic range is somewhat limited. Color looks about right, and exposure is pretty near accurate. The table below shows a standard resolution and quality series, followed by ISO, sharpness, saturation, and contrast series.
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 Optio 33L's lens is equivalent to a 38-114mm zoom on a 35mm camera. That corresponds to a moderate wide angle to a moderate telephoto. Following are the results at each zoom setting.
Good color with the Manual white balance, with good skin tones and high 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. Though maybe just a hint warm, I preferred the skin tones and overall color of the Optio 33L's Manual white balance setting here, but the Daylight and Auto settings produced good results as well, just slightly cool. The warmer cast of the Manual white balance creates slight purplish tints in the blue background that do not appear in the original image. Additionally, the deep shadow areas of the blue robe have similar tints. Resolution is high, with great detail in the embroidery of the blue robe. Like the house poster shots above, the 33L slightly underexposed these images as well.
A nice, small macro area with great detail, though flash has a tiny bit of trouble.
The Optio 33L performed well in the macro category, capturing a minimum area of only 3.09 x 2.32 inches (78 x 59 millimeters). Resolution is high, with strong detail in the dollar bill. The coins and brooch are soft due to the limited depth of field that comes with short shooting distances like this. There's once again a fair bit of softness in the corners of the image, most noticeable down the right-hand side. The Optio 33L's flash almost throttled down for the macro area, but overexposed the top center of the frame. There's also a small shadow in the lower portion of the frame. Overall, a pretty good macro performance, but plan on using external lighting for the closest shots.
Very good color, with only slight color casts.
All three of the Optio 33L's white balance settings that I tested produced great results here, with only slight color casts at each. I eventually chose the Manual option, though the Auto and Daylight settings were also quite good. The images are again slightly underexposed, so the Optio 33L distinguished the subtle tonal variations of the Q60 target well. Colors are slightly subdued in the large color blocks, and are a hint dark, but very good overall. Detail is moderate in the shadow area of the charcoal briquettes, with moderately low noise.
Good low-light performance, sensitive enough for average city street lighting at night as well as slightly darker situations.
With fully automatic exposure control and a maximum exposure time of four seconds, the Optio 33L isn't up to the standards of higher-end digicams for low light shooting, but does surprisingly well, and should easily handle city street scenes at night. Its adjustable ISO option helps quite a bit as well, letting you get usable photos even in very dark surroundings. The Optio 33L produced clear, bright, usable images down to the 1/8 foot-candle (1.3 lux) light level, with good color at the 400 ISO setting. At ISO 200, images were bright as low as 1/4 foot-candle (2.7 lux), and at ISO 100, images were bright as low as 1/2 foot-candle (5.5 lux). Since average city street lighting at night equates to about one foot-candle, the Optio 33L should perform well even in slightly darker conditions. Autofocus works well down to about 1/2 foot-candle (5.5 lux) too, and there's a manual focus option for settings darker than that. Noise is quite low, overall. Even at ISO 400, image noise is lower than I'm accustomed to seeing from consumer digicams. Overall, surprisingly good low light performance for an entry-level digicam. The table below shows the best exposure I was able to obtain for each of a range of light levels. Images in this table (like all sample photos) are untouched, exactly as they came from the camera.
Flash Range Test
Though intensity is slightly dim, consistent performance to 14 feet.
In my testing, the Optio 33L's flash illuminated the test target all the way out to 14 feet, without any significant decrease in intensity. In fact, at the 14 foot distance, intensity appears to increase just slightly. Image noise is a little high in the flash shots though, leading me to believe that the 33L "cheats" a little on its flash exposures by automatically boosting its ISO rating to get greater range. This works (and is a very common ploy among consumer digicams), but the tradeoff is increased image noise. Below is the flash range series, with distances from eight to 14 feet from the target.
Great resolution, with 1,050 lines of "strong detail." High barrel distortion.
The Optio 33L performed 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, and as low as 800 lines vertically. I found "strong detail" out to at least 1,050 lines. "Extinction" of the target patterns didn't occur until about 1,250 lines.
Optical distortion on the Optio 33L is high at the wide-angle end, where I measured approximately 0.97 percent barrel distortion. The telephoto end fared a little better, as I measured a 0.35 percent pincushion distortion. (Both numbers are higher than average though.) Chromatic aberration is very low, showing only about faint 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 noticeable distortion in most of my photos is fairly noticeable softness in the corners, although that effect is less visible in the res target shot here.
Resolution Series, Wide Angle
Resolution Test, Telephoto
Viewfinder Accuracy/Flash Uniformity
A very accurate LCD monitor, but no optical viewfinder at all.
The Optio 33L's LCD monitor is pretty accurate, showing approximately 98 percent frame accuracy at wide angle, and approximately 96 percent at telephoto. Given that I like LCD monitors to be as close to 100 percent accuracy as possible, the Optio 33L's LCD monitor has only a little room for improvement here. I do miss the presence of an optical viewfinder, although the 33L's LCD does better than most in bright light. Flash distribution is fairly even at wide angle, with just a little falloff at the corners and edges of the frame. At telephoto, flash distribution is more uniform.
33L Test Images
33L "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 33L, or add comments of your own!