The Pentax K10D is Pentax’s flagship camera, and is one of the most feature-rich cameras on the market, packing in a rain and dust-resistant weather-sealed body and one of the better autofocus systems in this class. While not class-leading, its high-ISO performance is very capable and can easily produce usable images at its maximum ISO1600.

In addition to its great high ISO performance, the K10D also has a built-in sensor-shift image stabilization method - a second generation “Shake Reduction” model which improves upon the performance of the budget K100D model, and according to a recent Popular Photography test, is comparable to the performance of the Sony A700 and Olympus E410 image stabilization. The Pentax K10D comes with the Pentax 18-55mm kit lens, providing a 27-83 zoom range, with an average f/3.5-5.6 aperture range.

The K10D has an effective pop-up flash (although not good enough to replace high-ISO and image stabilization as the primary low-light tools). The K10D also has a dedicated hot shoe for external flashes, such as the $130 Pentax AF200FG.

A relative newcomer to the Digital SLR industry (after it bought Konica Minolta’s SLR division), the Sony A100 was the company’s first foray into the SLR market. Using the same sensor as Pentax’s K10D (both sensors are made by Sony), the high-ISO performance on both cameras is fairly similar - a bit noisier than the Canon Rebel XT, but on the whole very good at high ISO and perfectly usable at even the maximum ISO sensitivity (ISO1600 for the A100).

The A100 has built-in sensor-shift image stabilization, which Sony calls “Super Steady Shot”. According to Popular Photography’s test, its performance is comparable to that of the other leading contenders.

The A100 comes with a Sony 18-70mm kit lens, which provides a 27-105mm zoom range, with a fairly typical f3.5-5.6 aperture range.

The A100 has a similar pop-up flash to other cameras which does better than the embedded flashes built into the camera body, but still produces fairly flat, harsh lighting. The A100 has a hot shoe for external flashes, such as the $180 Sony HVL-F36AM (a bit pricier than the entry-level flashes from other manufacturers).

Olympus SLRs have always been unique for their use of the “4/3” format - a system which utilizes smaller sensors that are a little more than half the size of the sensors found on most digital SLRs, and 1/4 the size of sensors found on 35mm ‘full frame’ digital SLRs. Because they use a smaller sensor, the high ISO output found on Olympus cameras is significantly worse than the output from most other digital SLRs, producing noisy images that also have less detail due to detail-smearing noise reduction. That said, the high ISO performance is still good up to the highest ISOs (ISO1600) and will produce perfectly usable pictures, just with more noticeable noise than the images produced by other digital SLRs.

The E410 has a sensor-shift image stabilization system of its own, which is comparable to the IS systems in the A100 and K10D cameras. The Olympus E410 kit comes with two lenses: an Olympus 14-42mm lens (giving a 28-84mm zoom range), and an Olympus 40-150mm lens (giving a telephoto 80-300mm zoom range). The 14-42 lens has a f/3.5-5.6 aperture, while the 40-150mm lens has an f/4-5.6 aperture, both fairly typical for lenses in this range.

Thee E410 has a pop-up flash which rises noticeably less than that found on other cameras (only 42mm above the lens, instead of the 54mm found on the Rebel XT, for example). While still significantly better than the on-camera embedded flash, the pop-up flash will tend to produce flatter light and harsher shadows. The E410 has a hot shoe for external flashes, like the $170 Olympus FL-36.