The Pentax Optio WP is neither impressive nor depressing in terms of performance, coming in slightly below average with a time of 3.6 seconds from power on to first shot, with a large chunk of that time devoted to focusing. Shot-to-shot time was about the same, or slightly longer with flash.
Shutter lag was apparent in bright-light testing at 0.9 seconds and 1.5 seconds in low light, which is where we found the camera's autofocus to lag behind. There's no AF illuminator to help out, so it was difficult to focus in low light unless there was a high-contrast edge for the camera to lock on.
Interestingly, the Optio WP comes with a focus limiter. Similar to those found on long SLR telephoto lenses, this feature limits the distance or focal length that will be used for autofocus, thereby providing faster AF. We noticed little difference in focusing speed, however, when this feature was activated -- we turned it off for shutter-lag testing -- but it might come in handy in difficult focusing situations.
Continuous shooting was steady at 0.8fps, regardless of resolution. The only difference was that high-quality settings limited continuous shooting to 9 frames, while low quality kept on shooting after more than two dozen frames. Nothing impressive here.
Because there's no optical viewfinder, you will depend on the LCD to compose your images, and under most conditions -- even underwater -- the LCD was generally usable. However, in bright sunlight, our reflection was more visible than the image we were trying to shoot.
We tested the Optio WP in a swimming pool and found it relatively easy to use underwater, although reviewing images while you're submerged doesn't give you the best view. But all functions are operational, and it's easy to change settings below the waterline.
The depth limit of 1.5m is certainly workable in a pool, and since we took pictures both below and above water, we weren't particularly concerned about the 30-minute time limit. But snorkellers need to be aware of both the depth and time limits. When you're chasing after pretty fish, 30 minutes can go by very quickly.
Overall, the Pentax Optio WP did a good job of capturing sharp, well-exposed images with accurate colour reproduction and a fair amount of detail. There were some exceptions due to poor autofocus and an auto white balance gone awry, but in general, we were pleasantly surprised at the quality of many of our test shots and the general lack of purple fringing and noise.
The camera's flash has a Soft setting, which lessens the output, but we found that, even with close-up shots, our images were underexposed using this setting. Macro mode worked much better at powering down the flash for relatively even exposures.
We tested the camera with and without the special underwater mode and found little difference in how blue the water was. This may be partly due to the fact that we were, by necessity, close to the surface where the light that produces colour is not yet affected by the water. However, when using the flash, you always need to be closer to your subject than anticipated.
Focusing underwater was hit or miss. While some of our test shots were crystal clear, others were softly focused. In part, this is due to the fact that water is not static, even in a swimming pool. Although the Optio WP displays the shutter speed on the LCD, it's not always easy to read, so we ended up shooting at slower shutter speeds than advisable considering the conditions. However, we were pleasantly surprised at how sharp, detailed and well exposed some of our shots were. We had no problems with fogging or other water-related effects, either.
Edited by Aimee Baldridge
Additional editing by Nick Hide