Hi Chad,
Thanks for the reply. I found this on the ASCOM site:
https://ascom-standards.org/Help/Developer/html/P_ASCOM_DriverAccess_Camera_Gain.htm
Does this mean that control of gain is indeed available via the ASCOM interface or that ZWO have not implemented that particular property ? If not implemented then are there any programs that use ASCOM and do set the gain by another means or is the ASI driver the best/only option to do this.
Many thanks
Robert