SPECS 2D-CCD, User Manual

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Manual V2.docx | Status 10.12.2015 | Version 1
diminishes the quantitative nature of the CCD and produces image smearing due to a
phenomenon known as blooming.
Hot pixels 6.6
Hot (or warm) pixels are individual pixels on the CCD with higher intensity than their
surrounding area. They can appear as small pixel sized bright points of light on longer
exposures.
Every pixel on the CCD has some charge leakage, and if exposed long enough, any pixel
would light up. On a long exposure, you will see pixels ranging from just barely visible to
possibly bright hot star-like points. There might be a few bright hot pixels, more
intermediate pixels, and lots of very faint ones, though an entire spectrum of brightness.
Faint hot pixels contribute to the noise in a picture. Although the hot pixels are randomly
distributed within the chip, they are in a fixed position.
All cameras on the market today have "hot pixels". Because the rate of charge leakage is the
same for a given pixel over time, the longer the exposure, the brighter it becomes. This
charge leakage is worse at higher temperatures.
SpecsLab Prodigy contains a routine to identify and remove hot pixels. These pixels are not
recorded or displayed. Please see the SpecsLab Prodigy manual for further details.
Figure 23. Identifying hot pixels in SpecsLab Prodigy.