The CMOSfB-Camera made by OES is a digital colour camera for astrophotography, that doesn't sport a CCD chip but a CMOS chip as the sensor. A CMOS chip has less sensitivity compared to a CCD chip and the colour filters in front of each pixel don't boost the sensitivity either but the sensitivity is still good enough for astrophotography. Compared to a CCD chip a CMOS chip has some advantages. First, the low price. Second, the approved production technology that ensures chips of supreme quality at a low price. Third, when read out the information of a CMOS chip is not lost. This feature permits to record and guide with the same chip. During the exposure a small area of the chip is repeatedly read out for guiding while the whole chip accumulates light at the same time. Using CCD chips two chips are necessary, one for the picture and one for guiding. This phantastic camera did cost me DM 700 (about US$ 300), but OES increased the price meanwhile to DM 1250 (US$ 530) which is still a bargain.

Features of the camera:

Colour and black&white pictures (Single shot and multi shot mode)
Capability of seeing the picture develop during exposure
Can be used as an autoguider
Capability of taking pictures and guiding at the same time (Self guiding mode)
Online focusing

Technical data:

Chip type: Hewlett-Packard HDCS-2000
Resolution: physicaly 640 x 480 pixels, squares of 4 pixels are grouped to colour pixels, logicaly 320 x 240 colour pixels
Pixel size: physicaly 9 x 9 µm, logicaly 18 x 18 µm (Chip size: 5.8 x 4.3 mm)
Dynamic range of the A/D-converter: 10 bit
Exposure times: 0,018 - 588 s
Chip temperature: -30°C below surrounding temperature (two stage Peltier element)
Dark current: max. 100 pA/cm² at 25°C

More informationen on the camera can be found on the website of OES (although only in German).