The Sigma Low-down

Sigma had a few new products to introduce at the show today. Their Foveon sensor based DP1 has a new partner — the DP2. Side by side they look pretty similar, but the DP2 comes with a 24.2mm F/2.8 lens (41mm equivalent) versus the 16.6mm F/4 (28mm equivalent).

In case you missed the Foveon low-down, here is a quick summary.

A typical CCD and CMOS image sensor uses a color filter in front of each photosite on the chip to make the sensor “see” color. Some photosites have green sensors, some have red and some have blue. Since a sensor is only picking up light that is filtered, the rest of the colors must be interpreted by examining what is happening in nearby sensors.

The Foveon concept (and I am going to simplify this greatly — my apologies) uses the inherent color filtering properties of the silicon on the chip so that as the light passes farther through the silicon different color is passed. So instead having a red pixel next to a blue it is like they are stacked on top of each other. This means that each pixel is full color and not a derived RGB.

Okay back to the DP series cameras.

Sigma kept hearing from photographers that they would like the image sensor quality of a digital SLR in a small compact camera. So that is what they did — the DP cameras take the same Foveon sensor in the Sigma SD14 SLR and put it into a smaller package.

Besides a lens change the DP2, the image process has been upgraded to the TRUE II engine for improved image processing performance. Unfortunately they don’t have a working model of the camera at the show.

That same TRUE II processor is also being used in the new SD15 SLR. This is a 14-megapixel Foveon sensor camera that you have to do some Foveon math to get that number with a 3-inch LCD. I wish I could say more about it but the specs aren’t finalized.

Sigma is not just about cameras, they also are a good option for lenses too. Since they supply lenses for use on many different mounts, many of the introductions at Photokina were related to exiting lenses but new mounts. For example the 500mm F/1.4 EX DG HSM is now released for the Four Thirds system. There are 1.4x and 2x converters for Sony, but a brand new lens first showing here is the 24-70mm F/2.8 EX DG HSM.

It uses Sigma’s Hyper Sonic Motor for quick focusing and is scheduled to come in Sigma, Canon, Nikon, Pentax and Sony mounts.