Model Design / Appearance (7.0)
The very bright matte aluminum finish and mirror-gloss accents make the Pentax Optio S55 gleam. The design is clean and uncluttered, but it doesn't quite fall into the same minimalist camp as the Nikon Coolpix S1 or the Sony DSC-T7.
The fit and finish of the unit we handled is very good, and the S55 feels like a solidly-built camera for its size. The various components come together without gaps or misalignment, giving the camera a good squeeze -- the kind you might give it when pulling out of a tightly-packed purse or backpack--didn’t cause creaks or groans.
There is an extra plane on the front face of the camera that bows out to either side for grip and also adds some visual interest to the camera's front face. The dominant 2.5-inch LCD on the back is encased in a thin black frame to help distinguish it from the rest of the camera body.
It would be too generous to say that the Optio S55 is elegant or beautiful, but the camera's design is pleasant. The controls and detailing on the Optio S55 are compromised but the general appearance remains acceptable.
Size / Portability (7.0)
At 3.5 x 2.5 x 1.1 inches (89 x 59 x 28 mm), the Pentax Optio S55 is fairly large for a compact camera, but still fits in most pockets and some very small purses. At 6.3 ounces, including batteries and media 
(SD data card), the camera is light enough to be ignored and provides the effortless portability sought in this type of camera styling. While many of the Optio S55's competitors (from brands such as Fuji, Sony, Casio, and Nikon) are thinner -- down to about 2/3 of an inch -- the width and height of the Optio S55 offers far greater handling and stability. The Optio S55 is able to blend portability and control beyond many similarly designed models, providing users with a camera they can easily hold on to and shoot with comfortably.
Handling Ability (6.5)
As any camera that's not on a tripod, the Optio S55 is more likely to deliver optimal results when the user holds it with two hands. The camera is more stable, more likely to be level, and less likely to drop to the floor. However, the majority of point-and-shoot users will probably opt for a single-handed shooting position and Pentax has designed the camera to accommodate both shooting styles.
When looking at the camera face on, the left side of the Optio S55's front face sports a sweeping curve capped with an embossed Pentax label. Surprisingly, the vertical branding is at the proper height and length to act as an effective finger support. Mirroring the right-hand grip, along the right side of the camera's front face is a similar yet truncated curve to place the left hand. This unfortunately does not function as effectively as the right-hand support, as the shape attempts to conform to the way fingers would naturally curl if the left hand were set on the camera the same way as the right hand. But most point-and-shooters will apply the supportive left hand differently - placing hands on the top and bottom of the frame, not across the front as they would their right hand - and Pentax seems to have overlooked this.
While the camera's silver-coated aluminum alloy frame is moderately appealing to the eye, the Optio S55 doesn’t contain any rubberized material or textured surface for gripping. Other than the two curves on the front of the camera, there is nothing applied to the frame to aid in handling or control. The relative weight and general density of the frame will help stabilize the camera, but the general design requires the zoom toggle control to double as a support and sacrifices functionality.
Control Button / Dial Positioning / Size (6.0)
The Optio S55 shutter release is a large, rectangular, glossy metallic button with rounded sides. Pentax deserves credit for making it as big as it is; however, the build quality leaves a lot to be desired. The button itself is feeble and sits on a lose spring. It doesn’t seem like the control will hold up too well for long term usage, but for a potentially sub-$250 camera, sacrifices have to be made.
The mode dial is just barely big enough to read, though it couldn't be much bigger on a camera this size. Most of the settings on the dial are denoted with icons. That's great, because the type for the "PICT" setting is vanishingly small. The dial's edge is heavily ribbed, making it easy to switch from setting to setting.
The On/Off button is in the middle of the mode dial. It is just about flush with the dial surface, and therefore a bit vulnerable to bumping and cumbersome to access. I decided to see just how vulnerable. I turned the camera upside-down and pressed it against a tabletop. That didn't turn the camera on, but when I turned it upside-down and pressed it onto a stack of paper, the camera sprang to life. This design will cause a fair amount of battery life to go to waste, and considering the extending lens barrel, it could lead to damage if the camera accidentally started up in a bag or pocket.
The zoom control is a small but prominent rocker, made of a single piece of plastic. The control protrudes significantly from the camera and is placed nicely for thumb operation; however, with the limited handling features provided, users are required to rely on the feature for stability as well. The other controls -- six buttons and a four-way controller --are also small, but adequately spaced. The three buttons to the right of the LCD display (Review, Help, and Menu) are all a bit loose and rattle when handled. This does not apparently cause any harm, but again, does not supply an overwhelming sense of durability. The small continuous mode dial might be tedious to access for users with larger fingers, given the limited space that's not consumed by the camera's oversized screen.
Menu (7.5)
Pentax uses tabbed submenus on the Optio S55, which makes navigation between options straightforward and relatively quick. The three submenus are: Record Mode, Playback and Set-Up. The submenus are relatively crowded, but Pentax compensates for this by implementing an “enlarged menu” option via the zoom control. The display doesn’t actually zoom, but the selected control appears in larger type and a more readable display. One potential problem with the feature is that the enlarged text appears centered over a black backdrop and omits all other information. This may be a bit confusing as users will lose the context of the particular setting within the menu; however, the magnified text is an option and will surely come in handy for more near-sighted users who have misplaced their glasses.
The Record Mode submenu includes the lion’s share of camera settings. They are: Image Quality (sets the pixel size of the image, as well as compression); Recorded Pixels (sets just the pixel size of the image); Quality Level (compression alone); White balance (calibrates the camera to a variety of light sources); Focusing Area (determines the area of the frame the camera will try to keep in focus); AE metering (selects how the camera will evaluate the scene when setting the exposure); Sensitivity (for setting the ISO, or level of light sensitivity of the camera); Frame Rate (frames per second the camera will capture in video mode); Instant Review (determines how long an image will display on the LCD after it is taken); Memory (allows the user to save other settings when the camera is turned off); Sharpness (selects how much the camera will process each image to make them appear more in focus); Saturation (sets the degree in which the camera will brighten or tone down colors); Contrast; and EV compensation (exposure compensation will brighten or darken images as they are taken). Many of these settings are overridden when the camera is set to most automated modes.
The Playback submenu offers controls that are related to images that have already been recorded. They are: Protect (secures images to memory so they cannot be accidentally erased); DPOF (for setting printing options for images, either via a PictBridge printer, or direct download at a photo lab); Slideshow (offers controls for a slideshow on the camera LCD or a television via the A/V cable); Resize (for shrinking an image); Image/Sound Copy (to copy files between the camera’s built-in memory and the SD memory card); Digital Filter (enables users to create a color effect on an image that is saved to memory); Record Voice Memo (to apply voice memos to recorded images); Quick Zoom (plays back images at maximum zoom); and Quick Delete (to shorten the process for deleting images).
The Set-up submenu controls a range of underlying settings and general camera parameters. They are: Format (to format an SD card or the built-in memory); Sound (adjusts the volume when recorded sounds are played back on the camera, and controls the alert sounds for various camera functions); Date Adjust (sets the time and date, as well as the date style); World Time (selects the time zone); Language (changes the menu language - interestingly, Pentax is making various editions of the camera, each with a different set of languages available); Screen setting (for adjusting the startup screen image, background color, and other effects); Video format (selects between PAL and NTSC); USB (sets the USB mode); Auto Power Off (to determine the length of time the camera will sit unused before shutting itself off to save battery life); Fn Setting (enables users to assign a custom function to the Help/Function button when the camera is not in Auto Select mode); and Reset (returns all the settings to their defaults).
Ease of Use (6.5)
The Optio S55 is very easy to use in its automated mode, and generally produces its best results in Auto-select mode. On the other hand, it's difficult to exert much manual control over exposure or focus, so attaining any degree of precision can be frustrating. There is no print or share button included on the Optio S55 body, as many similarly priced cameras tend to include due to the target audience and intended users of compact cameras within this price range. While there is a text magnification option available within the camera's menu, once enlarged, all other settings dropped off the screen making it mildly difficult to scroll through and utilize. The lack of endurance or reasonable use of battery life was also enough of a problem to make the camera more difficult to use. The camera is not difficult for any level user to adapt to; however, if ease of use and simplicity is a priority, there are far more straightforward cameras out there within this price range.
