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| The *ist D's autofocus system in A.F.C. mode did an amazing job acquiring and tracking birds in flight. This is the full frame. All photos by Mike Stensvold |
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| Fall fire season arrived right on schedule in Southern California, providing some challenging test subjects for the *ist D's 16-segment metering system and dynamic range. The camera handled them well, with good detail throughout, including nuances in the smoke. |
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Pentax enters the digital SLR arena with a dandy 6-megapixel model
Pentax has joined the ever-increasing ranks of interchangeable-lens digital SLR makers with the introduction of the compact *ist D. Featuring a 6.31-megapixel image sensor, good performance and lots of features, the new digicam accepts a wide range of Pentax lenses.
Exposure
Like the 35mm *ist introduced a few months earlier, the *ist D provides three metering systems: 16-segment, spot and center-weighted, selected by moving the metering switch at the base of the mode dial to the desired icon. And as with the *ist film camera, we found the 16-segment metering to be quite accurate in most situations. Spot metering (the area is indicated by a pair of semicircular brackets in the center of the viewfinder) is handy when you want to base exposure on a reading of a specific portion of a scene or subject, or want to check the scenic brightness range. Center-weighted metering is handy for old-timers who grew up with it, and is the only metering mode available when lenses that lack an A setting on the aperture ring are used on the camera.
A host of exposure modes (Pentax calls them Capture Modes with the *ist D) cover just about any situation and any type of user. For point-and-shooters, rotating the mode dial to the green mark provides fully automatic Green Program AE: the camera sets both the shutter speed and the aperture for proper exposure. The *ist D lacks the film *ist's Picture Modes (which automatically set the camera for shooting portraits, landscapes, close-ups, action etc.), but serious shooters seldom use those modes, and presumably most customers for this $1700 camera will be fairly serious about their photography. For serious shooters, there are P (Hyper Program AE), Tv (shutter-priority AE), Av (aperture-priority AE) and M (metered manual exposure control).
Hyper Program is Pentax's twist on shiftable program AE. The camera automatically sets both the shutter speed and the aperture for proper exposure, but you can change to a desired shutter speed or aperture by rotating the Tv (or Av) dial, and the camera will automatically adjust the other control to maintain proper exposure. The unique Pentax touch here is that you can return to the original shutter-speed/aperture combination at a touch of the green button. One of the custom-function menus allows you to choose the program line the camera will use: normal, high-speed (favoring faster shutter speeds), depth-of-field (favoring smaller apertures), and MTF (which maintains the lens's theoretical sharpest aperture).
In shutter-priority AE, you select the shutter speed you wish to use, and the camera automatically and near-instantly sets the corresponding aperture for proper exposure. Conversely, in aperture-priority AE, you select the desired aperture, and the camera sets the corresponding shutter speed to maintain proper exposure.
Hyper Manual mode lets you set the shutter speed and aperture yourself, like any manual exposure mode, and tells you when you've set what the camera considers to be the correct exposure (or how far from that exposure your settings are) via a bar graph in the finder. But it adds a couple of useful twists. First, if you press the AE-L button, you'll lock in that exposure value. You can then use the Tv dial to change shutter-speed/aperture combinations a la shiftable program AE, while maintaining the set exposure. Second, if you press the green button, the camera will instantly set the correct exposure—handy if something cool suddenly happens over there in bright sun while you're trying to set an exposure for a subject in shade over here. You can use the custom function menu to choose whether the camera will set this correct exposure via program AE (adjusting both shutter speed and aperture), shutter-priority AE (maintaining your selected shutter speed and just adjusting the aperture) or aperture-priority AE (maintaining your chosen aperture and just adjusting the shutter speed).
The AE-L button will lock-in the exposure for twice as long as the metering timer (you can choose how long the meter remains active from 3–30 seconds, via the custom menus), or until you press the AE-L button a second time. The button's location just to the right of the finder eyepiece makes it a bit of a pain for left-eyed shooters, but we managed. Just to the right of the AE-L button is the exposure-compensation button, which allows you to set up to +/-3 stops of exposure compensation, in 0.5-stop increments: Just press the button and rotate the Tv dial until the desired amount of compensation is displayed in the finder (and on the external LCD panel). There's also automatic exposure bracketing, which shoots three successive frames, the first uncompensated, the second with exposure reduced and the third with exposure increased; you can select bracketing increments of 0.5, 1.0 or 1.5 stops (or 0.3, 0.7 or 1.0 via the custom menus).
You can set ISO equivalents from 200 to 1600 by rotating the mode dial to ISO and rotating the Tv dial until the desired setting appears on the LCD panel atop the camera. Unlike some digital SLRs, the *ist D doesn't provide an ISO 100 setting, but it does permit a setting of ISO 3200 via the custom function menus.
Focusing
As you might expect, the *ist D shares the *ist film camera's autofocusing system, including the latest SAFOX VIII AF sensor, and 11 focusing points, which you can select yourself (by setting the focusing-point dial on the camera back to SEL and using the four-way controller to activate the desired point) or let the camera automatically select the appropriate one (the one covering the closest subject) by setting the focusing-point dial to AUTO. The active point glows red in the finder when the shutter button is partially depressed; if you'd rather it didn't, you can cancel this feature via the custom menus. Pressing the shutter button halfway down simultaneously activates autofocusing and metering; you can activate autofocusing independent of metering by pressing the AF button on the camera back. The AF system operates in light levels from EV 0 to 19 (ISO 200). When the flash unit is popped up, it emits an autofocus illuminator to assist autofocusing in dim light.
There are two AF modes, selected via a switch by the lens mount. In AF.S (single-shot AF), the camera locks focus once established, and you can't fire the shutter until the camera has focused on something. In AF.C (continuous predictive AF), the camera focuses as long as you keep the shutter button partially depressed (or depress the AF button), and you can make an exposure at any time, whether or not the camera has focused on the subject.
Of course, you can also focus manually, via the focusing ring on the lens, by setting the camera-body focusing switch to MF. (Some Pentax AF lenses have a push-pull focusing ring that lets you switch to manual focusing even when the camera body is set for autofocusing.)
Lenses
The *ist D provides full functioning with current autofocus FA J, FA and F Pentax lenses (i.e., those with Kaf2 and Kaf mounts, and an A setting on the aperture ring, if they have an aperture ring—J lenses don't). With manual-focus Pentax A-series lenses (Ka mount), you lose autofocusing and P-TTL flash capability. The camera does not support power-zoom functions.
As a favor to owners of older Pentax lenses, the *ist will accept older M-series (K-mount) lenses, and allow use of lenses that lack an A setting on their aperture ring, via the "F step other than A" feature in the custom function menus, but the camera then becomes fully manual—no metering, no autofocusing. It's definitely best to use current lenses, and thus obtain access to all of the camera's versatile features.
Our test camera performed well with the *ist D with the new Pentax-FA J 18–35mm f/4–5.6 AL lens that accompanied it, our FA 80–320mm f/4.5–5.6 zoom (which becomes a 120–480mm on the *ist D) and the FA* 200mm f/4 1:1 macro lens (which becomes a 300mm macro).
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