The ST-402ME is so sensitive one is vitrually guaranteed to find a guide star in the field of view no matter where it is pointed using SBIG's small eFinder accessory lens (1" f/4). The ST-402ME can autoguide or image, but like the ST-237A, it cannot do both at the same time. However, using SBIG's patented Track & Accumulate feature, a sequence of images can be captured and automatically aligned and stacked (co-added) as you go. The ST-402ME's internal relays allow the camera to autoguide almost any commercial telescope with an autoguider port. It will also control an external Relay Adapter Box for unusual telescope drives or older ones that need to be isolated electrically from the autoguider.

This single sensor camera is designed for light weight, low cost and high performance. The camera uses a monochrome CCD with an optional internal filter wheel and custom filters enabling it to do both high sensitivity B&W imaging and RGB/LRGB color imaging with the same camera. The CCD is centered in the camera body and is correctly spaced for Celestron telescopes having Fastar or Hyperstar optics. The camera body is all metal construction (black hard anodized aluminum). Single stage, regulated, thermoelectric cooling with fan assist is provided on the standard astronomical model. At 4 x 5 inches, the camera head is somewhat wider than the ST-237A, but it is only 1.8 inches deep with electrical connections on the side. This gives the camera the shortest possible protrusion from the rear of the telescope to allow maximum clearance when imaging objects in the north with a fork mounted telescope. This size and shape also makes it possible to put the filter wheel inside the camera, even though the KAF-0402ME CCD requires larger filters than the ST-237A. Electronic relays provide typical autoguider output from the RJ-11 jack, so the camera can be used as a highly sensitive autoguider with a larger field of view than most other autoguiders. While somewhat wider than the ST-237A, this new camera is still fine for all Fastar equipped telescopes. The additional width will not affect its use as a Fastar camera in the slightest.