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Pentax Optio S40 review: Pentax Optio S40

Pentax Optio S40

David D. Busch
5 min read
Flexible automatic-exposure options, easy manual focus, and histogram-assisted exposure adjustments will please snapshooters who want to fine-tune pictures on the fly, but the Pentax Optio S40 lacks the manual controls enthusiasts look for. This ultracompact, 4-megapixel Pentax loses points for its average image quality and performance, but its biggest shortcomings are found in optical and LCD viewfinders that give you the worst of both worlds. Pentax made a lot of good choices in designing this pocketable 6.5-ounce, 3.5-by-2.3-by-1-inch aluminum-alloy snapshooter. On top of the Pentax Optio S40, the large shutter-release button is right where you want it, and the knurled mode dial with center-mounted power button manages basic shooting modes, from a no-brainer Easy mode denoted by a happy face, through programmed exposure, movie, voice-recording, color effects, and scene modes.


Pentax Optio S40

The Good

Compact; excellent macro capabilities; easy-to-use manual focus.

The Bad

Tiny, inaccurate optical viewfinder; LCD panel difficult to view in bright sunlight; average performance.

The Bottom Line

Its viewfinder shortcomings affect outdoor use, but this ultracompact model for the point-and-shoot set is versatile and user-friendly.

Video-capture, voice-recording, and a good range of automatic-exposure modes are accessible via the top-mounted mode dial.

If you hate making a trip through a convoluted menu system for common settings, you'll love this Optio's double- and triple-threat control buttons, especially because four of them are user definable. The four-way control pad's arrows adjust the flash options; activate the burst mode or the self-timer; and cycle through normal Autofocus, Macro, Super Macro, and Manual Focus modes. Press the Function key, and the same arrows can change the resolution or the compression ratio or bump the exposure up or down 2EV in 1/3EV increments. Alternately, you can select your own special functions from other options, including exposure mode, white balance, ISO setting, and autofocus area.

The arrows on the four-way controller and the three surrounding buttons serve multiple purposes.

When the camera is set to Easy mode, the Function key pops up a useful help display on the screen that explains the functions of each control. The Display button turns off the LCD or gives you a screen with basic status information, a full-disclosure readout--including current ISO, white-balance, and exposure-mode settings as well as a live histogram--or grid lines perfect for those "rule of thirds" compositional moments. The histogram remains active when you're adjusting exposure settings.

Most of the other buttons on the Optio S40's back panel also serve multiple functions: the Trash button can erase the most recent picture or delete all the photos in the camera's internal memory or SD/MMC card; the Review button can review single photos, array nine thumbnails, and zoom in up to 12X if you want to examine the details of a shot.

Switching to Review mode and deleting photos is quick with the dedicated buttons.

You can access the Recording and Playback menus regardless of the mode you happen to be in. Just press the Menu key, and the LCD defaults to the one appropriate for the current mode. You can switch to the other menu or a setup screen by tapping the left or right control-pad arrows.

The Optio S40 has 11MB of internal memory, but you should budget for an SD/MMC card to increase its capacity.

The feature set on the Pentax Optio S40 is oriented toward snapshot photographers who find exposure compensation and a choice of automatic-exposure modes more attractive than manual f-stop and shutter-speed settings or even aperture- and shutter-priority options. You can choose multisegment, center-weighted, or spot-metered autoexposure; opt for Night Scene, Portrait, or Landscape mode; or shift into Picture mode, which includes 10 different scene variations with names such as Flower, Self-Portrait, Surf, Art Museum, Text, and Marine. Pentax makes an optional waterproof housing to go with the last option.

There's also a Two-In-One multiple-exposure mode that slices the frame in half and lets you expose each half separately, and a Panorama Assist mode that stitches a series of pictures together vertically or horizontally. A little fine-tuning is available, including manual adjustments for sharpness, saturation, and contrast, along with eight color and black-and-white effects. The 3X zoom lens has a range equivalent to 35mm to 105mm on a 35mm camera, and this Pentax's close-up capabilities really shine. Its autofocus system takes you down to 7 inches in Macro mode at any zoom setting and as close as 2.4 inches in Super Macro or Manual Focus mode. When you focus manually, the Optio S40 enlarges the center portion of the image on the LCD, a distance-scale bar appears, and you can adjust focus by pressing the four-way controller's up and down arrows.

Another useful feature is the ability to resize pictures to a lower resolution or to crop excess image area, then save the slimmer picture as a new file. You can also replace the original shot to stretch the storage space in the Optio S40's 11MB of built-in memory or SD/MMC memory card.

The camera's movie and sound capabilities are a mixed bag. It can record AVI clips (limited to 320x240 pixels) at a smooth 30 frames per second (fps) for as long as your memory card holds out. Sound on the clips is tinny but serviceable. A separate mode lets the camera double as a voice recorder, and you can also add voice memos up to 30 seconds in length to each picture.

Those who want to put themselves in the picture will like one of the two optional wireless remote controls, including a deluxe model that can activate the camera's zoom as well as the shutter release and the self-timer.

You can power the camera with rechargeable AA batteries or a CR-V3 lithium battery.

The tiny viewfinder and the relatively small LCD don't provide a very good view, especially in bright light.

Most of the Pentax Optio S40's performance figures were mediocre at best. The time from wake-up to first shot was a middle-of-the-road 4.69 seconds, and the shot-to-shot times of about 4.5 seconds (7 seconds with flash) seemed even longer during fast-moving action. The burst mode let us take 35 pictures at full resolution at a poky 0.5fps, but we managed to fill up a memory card with 512 shots in a little less than 10 shutter-finger-numbing minutes at minimum resolution and maximum compression.

The non-light-assisted autofocus was zippy enough to clip shutter lag down to 0.6 second under contrasty lighting conditions, but the delay doubled to 1.2 seconds under more difficult low-contrast illumination.

Viewing ease isn't one of this camera's strengths. To frame a shot, you must choose between a bright optical viewfinder that shows only about 80 percent of your image in a tiny, inaccurate window, and a 1.6-inch LCD that washes out in sunlight, even at the highest user-adjustable brightness setting. Indoors, you'll probably opt for the LCD, which shows 100 percent of the picture, but outside you may end up making the best of the microscopic optical window and wishing you had access to the bigger LCD view.

The Pentax Optio S40 didn't impress us with its average image quality. Although exposures were generally good, we frequently got underexposures with flash, and red eyes were often a problem, even with the Optio's red-eye-protection feature activated. We noticed a slight bluish cast to some pictures, and shadow detail was generally not as good as we would have liked. Highlights, however, tended not to blow out, and overall sharpness was good. We unfortunately encountered several clusters of dead pixels in our review unit, so do a little quality-control check on your images while your warranty is in effect.

Pentax Optio S40

Score Breakdown

Design 7Features 7Performance 6Image quality 6