iOptron CEM70 Instruction Manual page 51

Select "iOptron iGuider" camera. PHD2 will fill the pixel size (3.75um) automatically. Enter
120mm into guide scope focal length tab, and click Next.
If the program displays the following error, please exit "iOptron iPolar" software.
Select correct iOptron ASCOM driver from the dropdown menu. Here "iOptron ASCOM Driver
for CEM120/70 Mount" was chosen for a CEM70G mount. Click Next.
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