6: The mechanical box's surfaces
Here is the instrument cabinet opened.
First Göran shows the instrument's overview and outer parts that are included, in the image below we can discern the internal parts.
Here Göran had just taken the lid off. Look to the right and see the revolver for the coronagraph stick up and the camera
(grey) to left underneath the instrument.
The entire chassis and the internal parts are coated in a black color / anodizing to dampen reflections.
Reflections brings unwanted stray light into the detector and must be reduced to a minimum.
The camera has its range of sensitivity from the visible and well into the infrared range (infrared, above 650 nm).
The color that appears to be black to the eye does not necessarily mean that the camera see it as black.
IR can behave like that it could be reflected in black surfaces and one must carefully select the right type of surface treatment to obtain
adequate suppression of reflections over the entire wavelength range to be used, not easy when they directly to the eye are not visible.
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