A factor that needs to be considered for accurate digitization is noise. Noise is added signal from sources such as dark current, shot noise, and read noise, that is not part of the signal from the object being imaged. Noise reduces the dynamic range, which is the ratio of well depth to noise:
For example, a system with a well depth of 40,000 electrons and with a noise of 10 electrons would only have a dynamic range of 4,000 electrons. (Other examples are given in the table.)
With all this in mind, the true dynamic range and the systems digitizer together determine the true bit output. Following the above example, the best output would be as follows: For a CCD chip with a calculated dynamic range of 4,000 electrons, a 12-bit digitizer would allocate that to 4,096 gray levels. If the same information were to be translated by an 8-bit digitizer, the 4,000 electrons would need to be compressed into 256 gray levels, causing loss of information. Conversely, creating seemingly impressive data by the use of a 16-bit digitizer distorts the true data obtained into 65,536 gray levels, while adding no additional information.
Bio-Rads imaging instruments provide customers the truest data possible. We understand that true data is the most important part of your research. All of our CCD camera systems output data without computer-aided enhancements or digitization mismatching, ensuring accurate data acquisition. We acquire the best data by using large well depths and reducing noise. By clearly stating an ambient or true cooling method, and with back thinning (where appropriate), we excel at lowering n