According to Altairs “documentation” (the appended JPG is from their website Altair Hypercam 26C APS-C Colour TEC Astronomy Camera 16bit ), the range of gain setting goes from 100 to 10000. A gain setting of 100 in the Altair software corresponds to the lowest possible setting. There seems to be either a bug in the Altair ASCOM driver or a the way SGP communicates with this driver.
I would try the lowest possible setting. Important is also the choice of LCG (low conversion gain) of HCG (high conversion gain) mode. The resulting gain in electrons/ADU is given in the first graphic.
Bernd
