Sigma DP2s

After several years in the wilderness, Sigma was the first manufacturer to release a compact camera with a large-format SLR sensor. The DP was originally released in two versions: DP1 with a wide-angle lens and DP2 with a standard lens. A few updates and modifications later, Sigma has now released the DP2s.

Handling

The Sigma DP cameras reign supreme in a field that other manufacturers, with the notable exception of Ricoh and Leica, avoid like the plague: austerity. Although a video mode has now been added, it's the only concession to modernity Sigma seems willing to make. Otherwise, the camera looks like it came straight out of a Soviet factory sometime in the 80s.

Although the careful manufacturing, impeccably mounted lens, robust plastics and heavy weight of the camera (almost 300 g ready to use) give a reassuring impression of toughness and sturdiness, the smooth plastic body does nothing for grip, and the plastic dots don't help much to be honest. A rubber grip could have improved the camera's design and made it a little easier to keep hold of.

The camera starts up to the sound of a slightly unpleasant rattling noise as the lens come out (it extends to 26 mm, ready to shoot). Plus, a 2.5-inch screen with 230,000 dots is pretty unforgiveable on an expert camera in 2010.


The DP2s only has PSAM modes, which means the camera can only really be used by people who already have a decent knowledge of photography. The only wheel-based control is used for focusing and the buttons on the top-right corner of the rear face and the four-way controller are used to adjust exposure.

There are three different internal menus. The QS (Quick Set) menu offers access to sensitivity settings, flash, white balance and exposure metering, then to the burst mode and picture settings. The Menu button brings up a selection of more detailed picture settings. Finally, Setup (on the mode selection dial) takes you to the settings of the camera itself. Navigating though the menus is a pretty unique experience (see insert) and isn't as intuitive as the controls that most manufacturers have adopted as standard.

Responsiveness

Sigma is keen to point out that the DP2s is faster than the previous models. But while the previous models had a reputation for being so slow they were practically comatose, the DP2s is merely annoyingly slow in comparison. It takes over four seconds to start up, two and a half seconds to save a photo, the burst mode is limited to four frames etc. Next to all that, the autofocus of 1.4 sec. (twice as slow as a micro four-thirds or a decent compact) actually looks quite fast! At least, that's when the camera does actually focus, as it has serious trouble in low light.

We would have liked to be able to set the DP2s to the hyperfocal distance so as to get rid of the delay in focusing and take pictures at our own pace. But here too, Sigma hasn't been particularly helpful as even in manual focusing mode and in A mode there are no useful values, no hyperfocal distance and no depth of field. Ricoh does better in this field.

Picture Quality

It's difficult to judge pictures taken by the DP2s by modern standards. First of all, with 4.6 Megapixels, the definition is 60% lower than in most current entry-level compacts. Next, the structure of the Foveon x3 sensor (three layers of photodiodes, sensitive to red, green and blue respectively) is radically different to the sensors found in other cameras and, as a result, there's no low-pass filter and no image smoothing. The 4.6 Megapixels are, in theory, genuine Megapixels, with no blurring or demosaicing.

In practice, at 50 ISO the picture is incredibly accurate. Two neighbouring pixels can look genuinely different—something that never happens in cameras with Bayer filter sensors. Obviously, definition is nowhere near that of a 12-Megapixel sensor with a very good lens, but the DP2s can still reasonably be compared to a good 8-Megapixel camera (with an identical sized print, of course). The lens clearly has something to do with things too, as it captures detail with more accuracy than the sensor is capable of recording—and across the whole frame too.


High ISO sensitivity has never been a strong point for Foveon sensors. The first warning sign is that the DP2s actually stops at 800 ISO. It can go up to 3200 ISO but only using the Raw format rather than Jpeg. You'll probably want to avoid pushing up the ISO settings though, as Jpeg pictures have a green tinge from 400 ISO that gets even stronger at 800 ISO. Noise is very noticeable too, and the pictures won't be suitable for prints any bigger than 4" x 6".

In other words, above 200 ISO you have no choice but to use the Raw format to get the best out of this camera. But even then, you probably won't want to go any higher than 800 ISO.

To sum up, this camera could easily warrant four stars when used outdoors. However, in low light, it really only deserves two.

Video

The DP2s records QVGA video. However, this 320x240-pixel resolution was the standard on compacts released in 2003 (and even then, high-end models had already started to move to VGA). The resolution alone is bad enough, but to make things worse, sound is recorded in mono and is metallic and particularly unpleasant sounding.

In fact, this camera might as well have had no video mode at all, as this feels like a half-hearted attempt to tick a box.