The Starlight Instruments Handy Stepper Motor (HMS) unit works exclusively on the Focuser Boss II electronic focuser. The design of this motor housing allows you to still be able to manually turn the focus knob on the focuser by simply turning the over-ride knob on the motor housing. This motor has a built-in temperature thermistor for temperature control through the Focuser Boss II digital system.
The HSM20 has 19,450 steps per inch and the HSM30/35 has 24,300 steps per inch.
- The HSM20 will fit any Feather Touch Micro Focuser, Feather Touch retrofit pinion assembly upgrade, and Feather Touch Crayford Focuser.
- The HSM30 will fit any 2.5”, 3.0” and 2.0” Feather Touch Rack/Pinion Focuser, and Astro Physics 2.7” with Feather Touch pinion assembly upgrade.
- The HSM35 will fit any 3.5” Feather Touch Focuser, Astro-Physics 3.5” and 4.0” with Feather Touch pinion assembly upgrade.
For heavier image trains and non Feather Touch Focusers, Starlight Instruments offers the Posi Drive Motor System (PDMS) which can lift in excess of 56 pounds.