RainbowRobotics RST-300 Mount
RainbowRobotics RST-300 MountRainbowRobotics RST-300 MountRainbowRobotics RST-300 Mount
RainbowRobotics RST-300 MountRainbowRobotics RST-300 MountRainbowRobotics RST-300 Mount

RainbowRobotics RST-300 Mount

£8,995.00✓ 2 year warranty


Special shipped 10-15 working days

About this product

Model:  rr_rst-300
Part Number:  MNT000800

New RST-300 Weightless Mount - Huge 30kg Payload Capacity!

Counterweights no longer required!

The exciting new RST-300 uses a new and highly innovational type of gear. Due to the strong force of the Strain Wave Gear and the Motor, a counterweight is not needed. 

This is the bigger brother of the popular and highly thought of RST-135 mount taking all the learnings of the smaller mount and improving upon the tried and trusted design with additions of a built-in brake which activates when the mount is switched off and holds the payload in position.

The mount weighs only 8.5kg but is capable of accepting a telescope with weight up to 30kg (maximum 50kg).  Rainbow call this a "Weightless Mount"

The RST-300 is still a portable mount with excellent astrophotography potential that is ideally suited for using in the field and also in observatory setups due to it's huge payload.

The Rainbow Astro RST-300 mount utilises robotics technology that has been widely used in precision industrial robotics applications, strain wave gears provide zero backlash and a high degree of pointing and tracking accuracy.  

This unique mount has the ability to function as either an EQ or AZ mount and can carry up to 30kg without the use of a counterweight shaft or weights.  Weighing just 8.5kg and compact, the RST-300 is very portable and is a perfect option for travel astrophotography with larger payloads.

Smart features like built in Wi-Fi, a homing sensor and GPS allow for remote control and guiding of the mount.   Built from solid block CNC construction, the Rainbow Astro RST-300 is solid with smooth operation for reliable performance.

Tripod pictured not included ;-)


  • Weights only 8.5kg but has a massive 30kg capacity without counterweights, 50kg with counterweights.
  • Strain wave gear / Harmonic Drive - no backlash!
  • Dual mode - equatorial / alt-az
  • Extremely fast slewing - 5º / Second
  • Low power consumption - 0.4A tracking / 4A slewing (at 12V)
  • Light and compact, great for portable setups with larger payloads
  • Beautifully machined from solid metal - premium fit and finish
  • ASCOM driver support
  • Built-in WiFi, GPS and Home Sensor

Counterweights Not Required

Counterweights not required up to 30kg. You can prevent accidents by the observer or guest from hitting the counterweight. Since there is no need for a weight bar, it is good for wide use of a narrow observation room.

Freed from balancing

The performance of the worm gear mount is sensitive to the balance, but the RST-300 is not. When two telescopes are mounted side by side, it is difficult to balance left and right, but using the RST-300 does not have such difficulties. You don’t need to rebalance if you change accessories like a camera or guide scope.

Strain Wave Gear(Harmonic Drive)

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.

Built-in brake

The RA axis has a built-in brake system. When the mount power is off, the brake is activated to prevent the “back drive” phenomenon. “Back drive” refers to the phenomenon that the shaft rotates in the direction of gravity when the power of the strain wave gear mount is turned off.

CNC Machining

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

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

Home Sensor

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-300 mount.

Product Videos

What's in the box

  • RST-300 mount
  • Hand controller (Hubo-i SE)
  • Cable for hand controller
  • USB cable
  • Power cable (Cigarette Lighter Plug)
  • Power cable (5.5×2.1 DC Jack)
  • AC-DC power adapter
  • Adapter for PoleMaster
  • Soft case
  • 5mm Hex Wrench




Mount type Dual mount – German Equatorial, Alt-Azimuth
Gear Strain wave gear (Harmonic Drive)
Load Capacity 30kg(without counterweights), 50kg(with counterweights)
Recommend Telescope 12inch Reflector, 7inch Refractor
(without counterweights)
Weight 8.5kg
Volume 18.3 x 17.5 x 27.9 cm
Material Aluminum alloy AL6061, Steel, Brass
Surface coating Anodising
Gear size(RA) Model No. 25 (Based on HDS)
Gear size(DEC) Model No. 25 (Based on HDS)
Motor Swiss made Maxon DC Servo Motor
Latitude range 0 to 90 degrees


Max Slew Rate 1,200x (5deg/sec) – 16V DC
Input Power DC 12V ~ 16V
Power Consumption(Tracking, 12V) 0.4A
Power Consumption (Slew, 12V) 4.0A
PC Connection ASCOM Driver
GPS Built-in (Hand Controller)
WiFi Built-in (Hand Controller)
Home Sensor Built-in
Brake Built-in RA axis : To prevent back-driving
High voltage, reverse polarity input protection Built-in

Customer reviews

Be the first to Write a Review for this item!


Please fill in the form below to ask a question.

Please add the two numbers