Pentax provides lots of customization options on the *ist DS. There are 18 custom functions, ranging from the mundane, such as designating how long the exposure meter stays active or whether automatic noise reduction is applied, to the sublime--for example, disabling the shutter-release button while the flash is recharging or setting the magnification to use when reviewing images on the LCD.
Picture-review options are fairly standard for a camera in this class. You can view the images taken, rotate them 90 degrees (manually; the *ist DS doesn't do this automatically), and zoom in at up to 12X magnification to examine fine details. A nine-thumbnail display simplifies finding the image you want quickly, or you can show photos consecutively in slide-show mode. You can also apply sepia, black-and-white, soft-focus, and "slim" effects to your images in the camera, which saves the altered files under new names. This Pentax supports DPOF functions for marking images for printing, as well as PictBridge for direct output to compatible printers.
Although the *ist DS doesn't ship with a rechargeable battery and charger, its two CR-V3 lithium cells can be replaced with four AA batteries of your choice. The battery options work nicely with the camera's compact design to make it a practical choice for traveling photographers.
The responsiveness of digital SLRs, compared to point-and-shoot digitals, is one reason why photo enthusiasts lust after them. In this respect, the Pentax *ist DS neither disappoints nor excels in comparison to the competition. You can flip the power switch and take a picture 1.3 seconds later, then snap off shots every 0.9 second until the buffer fills five shots later. Using the built-in flash increases the interval to about 2.2 seconds between shots. Shooting raw doesn't impose much of a penalty; this camera is able to snap images every 1.2 seconds when saving unprocessed files.
For action sequences, the *ist DS can grab eight images in 3.1 seconds at full resolution in drive mode, which actually is better than it was able to muster when we bumped resolution from 6 megapixels down to the 1.5-megapixel minimum, and bursts were limited to seven frames in 3.3 seconds.
Shutter lag is a negligible 0.2 second with the 11-point autofocus system operating at full steam under high-contrast lighting conditions but can be cut to 0.1 second if you're focusing manually. The lack of an autofocus-assist lamp makes the Pentax stumble under more challenging low-contrast lighting conditions, but shutter lag is still a minimal 0.6 second.
Under most conditions, the autofocus system is robust and speedy, tracking subjects accurately when the continuous AF feature kicked in with the Moving Objects (action) mode. The default focus system is single autofocus; continuous autofocus for tracking moving objects is available only when you're using the Moving Objects mode. You can choose any of the 11 zones shown in the finder to set focus, although the control to activate this option is tucked away in the menu system under the cryptic name Swtch dst msr pt.
It's easy to manually fix the focus on the viewfinder's bright matte focus screen, which you can interchange with optional split-image and scale matte replacement screens. That's an exceptional feature on a camera of this class. The optical viewfinder itself bests the competition by using a real pentaprism instead of a pentamirror and provides a 0.95X magnification showing 95 percent of the frame. The Nikon D70's 0.75X, mirror-based viewfinder looks tiny and dingy by comparison. The *ist DS's view makes it easier to confirm focus or to focus manually, and the larger high-res LCD simplifies reviewing images, too.
Although tiny in size, the built-in flash provided even room-filling illumination. Its preflash offered some of the best red-eye reduction we've seen, producing nice white catch lights in the eyes with no trace of demonized pupils.
We liked the images this compact dSLR gave us. Shortcomings such as color casts and JPEG artifacts could be easily fixed in an image editor or by shooting raw files instead of JPEGs. Unfortunately, you can't shoot raw files and JPEGs simultaneously with the *ist DS, which is a feature that most of its competitors offer.
The Pentax *ist DS produced uniformly good exposures with lots of detail in the shadows and highlights and had a slightly lower tendency to blow out the whites than its competitors. Skin tones were neutral and lifelike, although some colors, especially the reds and oranges, were often more saturated than we'd like, at times verging on the garish. We also noticed a bluish cast in the images, particularly outdoors.
Image noise levels were competitively low, with clean images at ISO 200, some multicolored speckles popping up at ISO 400, and a more confettilike look being produced at ISO 1,600 and above. Although we don't recommend the noisy ISO 3,200 setting for most purposes, it's notable that this camera offers it at all since other cameras in this class don't.
With the kit lens, purple fringing was very mild but visible around backlit subjects.