Like the K2000 / K-m before it, operation of the Pentax K-x digital SLR is largely as straightforward as you'd expect from a consumer DSLR, although it does manage to offer a few fairly unusual features such as high-dynamic range photography and a cross-processing effect. The large Mode dial on top of the camera controls the main operating modes, and hints at one of the main changes from the K-x's predecessor. It has the usual Pentax consumer SLR options for Auto Picture, Program, Sensitivity priority, Shutter priority, Aperture priority, and Manual, plus a variety of Picture and Scene modes, but also now includes a Movie setting. See the Modes & Menus tab for details on the various exposure modes.
Several of the Pentax K-x's control buttons perform multiple functions, which saves space and time. The e-dial for example controls a variety of settings when turned in combination with a press of a button, and the arrow keys of the Four-way arrow pad access shortcuts to common camera settings as well. The Pentax K-x's LCD menu system is straightforward, with four main menus accessible via a tabbed interface at the top of the screen. Considering the multi-functional controls and variety of menu options, it will probably take most users a little time with the manual to really get the gist of things, but operation becomes intuitive after that.
The Pentax K-x's main TFT color LCD monitor is used for status display, accessing menus, image review as well as image preview in Live View mode. At 2.7-inches, the LCD panel is a little smaller than the 3-inch panels found on many SLRs these days, and resolution is a fairly ordinary 230,000 dots (approx. 320x240 RGB pixels), and also features a wide viewing angle. The LCD's brightness can be adjusted in 15 steps, and color can be adjusted in 15 steps on a 2-dimensional Green/Magenta vs. Blue/Amber color grid for a total of 225 combinations. You can adjust the color while viewing a captured image in the background, useful for matching your computer monitor. You can also adjust the display color scheme, choosing from six presets, and set the text size, selecting between "Standard" and "Large" fonts.
Status Display When you turn on the Pentax K-x, the main LCD displays a status screen by default, showing the current record mode settings. The display can be switched off, and through the camera's Memory setup this can be made the default after power-up as well. The status screen updates in real-time while adjustments are made, and by pressing the Info button it can be replaced with an interactive Control Panel screen that allows certain settings to be changed without the need to enter the menu system. Both the Status and Control Panel displays automatically flip between landscape and portrait mode displays depending on the orientation of the camera. There's also a Guide display which appears briefly when you change exposure modes. The time it is shown can be changed, or it can be completely disabled in Setup Menu 1.
See the illustration (courtesy of Pentax) and table below for detailed information:
Control Panel Display When the INFO button is pressed, the Status screen changes to a Control Panel display, allowing direct access to both commonly adjusted settings and some less commonly adjusted settings without the use of the menu system. The Control Panel display will disappear automatically after 30 seconds of non-use, reverting back to the Status display above (if enabled), or a blank screen. As well as pressing the OK button to select and adjust an item in its own screen, it's also possible to simply roll the e-dial while an item is highlighted, making the settings change without ever leaving the control panel display.
See the illustration below (courtesy of Pentax) for detailed callouts of the settings available in the Control Panel display.
JPEG Recorded Pixels
Lateral Chromatic Aberration Correction
Date and Time
Remaining Image Storage Capacity
Select AF Point
Playback Mode Displays In Playback mode, the default image display shows the most recently captured image, with a modest information overlay present. Pressing the Info button once pulls up the Pentax K-x's histogram view. Pressing the up or down arrow switches between a luminance histogram and an RGB+Luminance histogram set. Any overexposed areas in the frame also blink, if the option is selected in the Playback menu. Pressing the Info button again brings up a detailed information display, which decreases the image to a thumbnail on the screen. All of the same information is reported here as in the detailed display in record mode, listed above. Pressing the up or down arrow switches between this page, and one showing the photographer and copyright holder information if recorded for a particular image or movie. A third press of the Info button brings the image back fullscreen, with no information. In all display types except the RGB+Luminance histogram and the detailed information display (where the thumbnail is too small for it to be feasible), any clipped areas in the frame blink if the option is selected in the Playback menu. Under-exposed areas blink in yellow, while overexposed areas blink red.
Turning the e-dial in this mode controls the index display and image enlargement options. The index display can show 4, 9, 16, or 36 thumbnail images at a time on-screen (the default is 9; pressing the Info button allows you to select the number of thumbnails shown), while the enlargement feature magnifies images as much as 16x. There are also display-by-folder and display-by-shooting-date (calender) options. A handy "Compare Images" mode lets you display two images side-by-side, which can be enlarged to 16x as well. When viewing by shooting date, all dates for which there are images or videos are listed down the left-hand side of the screen, with blue headers for the year and month, and the days for each month grouped beneath the header listing the day of the week and date. Near the bottom right of the screen is a strip which can scroll through up to four thumbnails from the date in question, beneath a larger preview of the currently selected image.
Finally, a particularly unusual feature is that the Pentax K-x lets you examine two images side-by-side, by pressing down arrow while viewing an image or video, then selecting the Image Comparison icon. Since there's only one control dial, this mode is rather cut down from that in the company's prosumer K-7 digital SLR, which allows each image to be separately zoomed and panned to view the desired areas, after which both images can be zoomed or panned simultaneously from this preset starting point. In the K-x the comparison mode is much simpler, only allowing linked control of zoom and pan for both images simultaneously. It's perhaps a little easier to learn to use in this manner, but lacks the versatility of being able to compare the same areas of images with significantly differing zoom or composition side by side.
While in playback mode, you can of course manipulate captured images. Options available are rotation, applying digital filters, resizing, cropping, and RAW development. You can even join multiple images together into a sort of index print, using a number of templates including Thumbnail, Square, Random, and Bubble. There is also a slideshow mode available.