Although the most compact of the sub-£600 digital SLRs, the Pentax *ist DS is not a lightweight when it comes to functionality. Packed into its 850g (with 18mm-to-55mm lens, battery and media), polycarbonate-clad, stainless-steel frame is an array of automated and user-selectable exposure and scene controls, a brilliant optical viewfinder and LCD that are easy on the eyes, and enthusiast-pleasing options such as an eight-frame, 2.5fps drive mode. In some ways, the *ist DS is an upgrade from its more expensive *ist D sibling, trading a few minor features for some significant improvements.
The newer, lighter Pentax offers only 6-, 4-, and 1.5-megapixel resolution settings, lacks TIFF mode and includes fewer presets for white balance and user-set modes. But the *ist DS adds seven scene modes; a larger frame buffer that boosts drive mode performance; more flexible saturation, sharpness, and contrast adjustments; and a back-panel, 51mm (2-inch) colour LCD with a whopping 210,000 pixels versus the 118,000-pixel, 46mm (1.8-inch) LCD of the elder Pentax. The *ist DS also uses SD memory cards instead of CompactFlash and has faster USB 2.0 picture transfer instead of USB 1.1.
Excellent performance and good image quality make the *ist DS an attractive option for those who don't already own a bag full of Canon or Nikon lenses, or who do have a stockpile of Pentax optics.
The first thing you notice about this camera, apart from its unpronounceable name, is its small size. At 124 by 94 by 66mm without a lens, the Pentax *ist DS is the size of a typical fixed-lens electronic viewfinder (EVF) camera. No digital SLR is pocketable, but this is one enthusiast camera that won't dominate your carry-on luggage.
This Pentax fits nicely in large or small hands and is well balanced enough to allow one-handed shooting. There are fewer buttons and controls on the camera than on the larger *ist D, and there's only one command dial, but the common functions that most often require a trip to the menu (ISO, white balance, flash mode and drive mode/self-timer/remote/bracketing controls) pop up at the press of a Function key and can be set via the four-way cursor control pad with embedded OK button. We didn't miss using separate buttons for these functions.
The top surface houses a built-in electronic flash with a slide-out hotshoe cover, a mode dial that includes scene modes, a shutter release with a concentric power switch/depth-of-field preview control built into the top of the handgrip, a monochrome status LCD, and a button that you use with the back-panel command dial to apply exposure compensation or set the aperture or the shutter speed. Separate command dials are more convenient, but the Pentax's single-dial system is easy to use. Unlike the status panel on some other digital SLRs, the *ist DS's display goes to sleep when the camera isn't being used; you tap the shutter button to revive the display.
Because several controls have been tucked away in the Function menu, the back panel of this Pentax is very clean. On the left side of the LCD, there's a button to raise the built-in flash when using modes that don't pop it up automatically, plus menu, trash, display info and picture-review keys. On the right are the cursor/OK pad, the Function button, a storage-access LED next to the SD card door release, and an auto-exposure lock button. You can spin the command dial with your thumb without changing your grip.
They may call this type of camera a single-lens reflex, but that doesn't mean you're limited to a single lens. The Pentax *ist DS accepts K-, KA-, KAF-, and KAF2-mount lenses directly, but you can also use Pentax screw-mount lenses dating back as far as the mid-1960s, as well as bayonet-mount lenses for the Pentax 645 and 67 120/220 roll-film SLRs, with an appropriate adaptor. This legacy-lens versatility partially neutralises the comparatively fewer lenses available from Pentax than from rivals Nikon and Canon.
Pentax aims to remedy that shortfall by introducing a line of digital-only lenses, including the DA 18mm-to-55mm f/3.5-to-f/5.6 optic supplied with the *ist DS kit. Equivalent to a 27.5mm-to-84mm zoom on a 35mm full-frame camera, this 224g, 12-element lens includes aspherical elements and uses economical 52mm-diameter filters. Focusing as close as 380mm, this zoom unfortunately suffers from an outrageously slow maximum aperture of f/5.6 at the telephoto end of its range.
Shooting options will please seasoned photo enthusiasts and novices alike. The programmed automatic, aperture-priority, shutter-priority, manual and bulb modes make it easy for experienced shooters to use settings creatively. There are also five basic scene modes for Portrait, Landscape, Macro, Sports and Night Scene Portraits, plus a Normal mode without special settings -- marked by an inane happy face icon -- and a flash-off option that uses the Normal settings while disabling the pop-up speedlight. For the neophyte who can't decide which scene mode to use, there's an Auto Pict setting that analyses the image and selects one of the scenes automatically.
The exposure system uses 16-segment multipattern evaluative metering complemented by centre-weighted and spot options, choosing shutter speeds from 1/4000 second to 30 seconds over an ISO range of ISO 200 to ISO 3200. Exposure can be calculated based on the sharpest focus zone or independently, at your discretion. Exposure compensation can be set to ±2EV in increments of either 1/2EV or 1/3EV.
The built-in flash has an ISO 200 guide number of 51 (in feet, ie 15.5m) and a coverage angle roughly equivalent to that of a 20mm lens. Pentax dedicated TTL flash units such as the AF360FGZ connect to the hotshoe or operate in wireless mode and can provide high-speed flash at shutter speeds faster than the default 1/180-second synchronisation rate. This Pentax supports slow sync, front-curtain and rear-curtain flash modes. While there is no PC-sync port or wireless control for using third-party external flash units off-camera, an adaptor for either can be slipped into the hotshoe, too.