May 2010
 Recording scenes with both very bright and very dark areas within the same image is a real challenge for normal linear CCD cameras with a limited dynamic range, especially where it is necessary to use compact 8 bit data with only 256 grey levels.
CMOS sensors of the active pixel type have been designed that attenuates the bright pixels in an image without influencing the darker pixels. The result is a software-controlled response to light that is linear at low light intensities and approximately logarithmic at high intensities.
Such sensors have been used for surveillance video applications for some time, but now high-performance sensors with machine-vision quality image quality, megapixel resolution and high frame rate are available with high dynamic range.
Cameras with high-performance CMOS sensors include the MV1-D1312 series cameras from Swiss Photonfocus with frame rates up to 160fps at 1.3 Megapixel, and the Fastec HiSpec high-speed cameras with 500fps at 1.3Megapixel.
In an article in Danish trade magazine Teknisk Nyt, Finn Mengel shows examples of the application of the Photonfocus cameras in machine vision and bar code reading. Also shown is an application of the Fastec Hispec for industrial troubleshooting, where nonlinear compression is the key to obtaining videos with good contrast.
 Read article (in Danish)
Read more: Photonfocus MV1-D1312
Read more: Fastec Hispec
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