Specifications

options for every exposure type separately. So it is possible e.g. to define
separate folders for dark frames and for flat fields.
Always check whether new image processing options are defined properly
before you start any exposure.
If you choose “Dark” from “Exposure” combo box (remember the image
handling options on the right side changes – make sure they are properly
defined), image will be captured without opening the shutter. The captured
image will represent the thermal noise, generated by the CCD chip itself,
combined with the CCD chip and camera electronics read noise. Such images
are subtracted from normal images during image calibration to reduce the dark
current effects.
Brightness and Contrast – Image Stretching
The G2 CCD dynamic range spans 65 536 levels. But only imaging of perfectly
illuminated and perfectly exposed scenes can result in images with pixels
spanning this range. Usually only a fraction of this range is used, e.g. the black
background can have values around 500 counts and the brightest part of the
image can have around 10 000 counts. If we assign the black to white range to
the full possible range (0 to 65 535), the image with 500 to 10 000 counts will
be displayed only in dark gray tones. This is why image brightness scale should
be “stretched” before they are displayed.
Open the “Histogram and Stretch” tool .
Illustration 16: Histogram and Stretch tool
The exact meaning of the histogram chart is explained in the SIMS software
documentation. Now only try to play with “Low” and “High” count-boxes or
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