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Stargazing Aug 31st ✦ 7pm-10pm
Stargazing Aug 31st ✦ 7pm-10pm

RST-135E Weightless Mount


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  • Counterweights Not Required

  • Only 3.4kg weight

  • ±2.5arcsec PE

  • Capacity 13.5kg (max 18kg)

  • Strain Wave Gear (Harmonic Drive)

  • Renishaw encoder

  • 5-years warranty


    Although the capacity is 13.5kg (maximum 18kg), the weight of the mount is only 3.4kg. It fits in one hand, so you don’t need a separate large bag for this. The lighter the mount, the greater the frequency of use.

    A high-resolution encoder from Renishaw is built into the RA axis. As a result, a periodic error of only ±2.5 seconds was achieved. Choose the RST-135E mount if you are bothered or reluctant to use the autoguide system.

    Counterweights not required up to 13.5kg. It is especially convenient for domestic mobile observation as well as overseas expedition observation.

    The performance of the worm gear mount is sensitive to the balance, but the RST-135E is not. No need to rebalance even if you change the eyepiece or camera.

    Instead of worm gears, a new type of reducer called strain wave gear (harmonic drive) is used. Almost no backlash and no maintenance is required. As it is widely used in industrial robots, it is very durable.

    CNC machined aluminum alloy AL6061 is used for aircraft. That’s why it’s small, light and stiff. The beauty of the machined surface increases the collection value.

    WiFi is built in. You can control the mount via the SkySafari app on your smartphone. Ascom Driver can be connected via WiFi as well as USB. GOTO and AutoGuide are now wireless.

    GPS receiver is built in. The position and time of the observer can be entered accurately and conveniently.

    There is a built-in home sensor to find the mechanical origin. This is useful for permanently using Star Alignment data. Build an ultra-small remote observatory with the RST-135E mount.


    Mount type Dual mount – German Equatorial, Alt-Azimuth
    Reducer Strain wave gear (Harmonic Drive)
    Load Capacity 13.5kg(without counter weight), 18kg(with counter weight)
    Recommend Telescope 8inch Reflector, 5inch Refractor
    Weight 3.4kg
    Volume 14.4 x 13.1 x 20.5 cm
    Material Aluminum alloy AL6061, Steel, Brass
    Surface coating Anodizing
    Reducer size(RA) Model No. 17 (Based on HDS)
    Reducer size(DEC) Model No. 14 (Based on HDS)
    Motor Swiss made Maxon DC Servo Motor
    Latitude range 0 to 90 degrees
    High resolution encoder

    Built-in RA axis, Renishaw


    Max Slew Rate 1,800x (7.5deg/sec) – 16V DC
    Input Power DC 12V ~ 16V
    Power Consumption(Tracking, 12V) 0.2A
    Power Consumption (Slew, 12V) 1.0~2.0A
    PC Connection ASCOM Driver
    GPS Built-in (Hand Controller)
    WiFi Built-in (Hand Controller)
    Home Sensor Built-in
    Compatibility ASIAIR, StellarMate
    Periodic error ±2.5arcsec (430sec)



    • RST-135E mount

    • Hand controller (Hubo-i SE)

    • Cable for hand controller

    • USB cable

    • Power cable (5.5×2.1mm DC)

    • Adapter for camera tripod(3/8″ thread)

    • Adapter for PoleMaster

    • Soft case for mount

    • 4mm Hex Wrench