Estimated 14 days lead time
Need advice about this product?
Explore UMi 20S
A compact mount that carries serious imaging rigs. The UMi 20S pairs a 5.4 kg mount head with a 22–30 kg payload range, balancing field portability with capacity for multi-instrument setups. It is designed for guided astrophotography where higher payload and transportability matter.
High-capacity strain wave gear mount
22-30 kg payload range with a compact 5.4 kg mount head
Dual-servo drive system
Dual-axis anti-collision system
Mechanical home position
Carry heavy imaging trains while keeping the mount itself easy to move. The UMi 20S specifies a payload range of 22–30 kg and a mount head weight of 5.4 kg, letting you mount larger scopes, cameras and accessories without an overly bulky head to transport.
Strain wave gearing and a dual-servo system provide torque and responsive control needed for guided long exposures. The RA uses a type-20 strain wave gear and the Dec uses a type-17, with quoted periodic error of plus or minus 10 arc-seconds. Direct drive and dual-servo design support modern guided imaging workflows.
Designed for remote or automated setups, the mount includes a mechanical home position for reliable return-to-home and a dual-axis anti-collision system to help protect gear. These features suit unattended imaging or observatory use where predictable positioning and safety matter.
Proxisky - UMi 20S
ProxiSky UMi20 Review
The specified payload capacity is 22–30 kg, listed as without/with counterweight.
The mount head weight is specified as 5.4 kg.
The mount uses strain wave gears with a dual-servo motor system: RA is a servo with a type-20 strain wave gear, Dec is a servo with a type-17 strain wave gear.
Periodic error is quoted as ±10 arc-seconds.
Communication options include USB, Bluetooth, Wi-Fi, ST4 and control through the UMi Mount app.
Yes. The UMi 20S has a mechanical home position and a dual-axis anti-collision system.
Power input is listed as 12–24 V at 3 A.
The package contents listed are: Proxisky UMi 20S mount, hard case with EVA foam, Male-Male DC 5.5-2.1 cable 1 m, Type-B USB 2.0 cable, hex screwdriver, and counterweight bar.
| Mount type | German Equatorial / Alt-Az |
| Drive system | Strain wave gear |
| Control system | OnStepX |
| RA axis | Servo motor, type-20 strain wave gear, direct drive |
| Dec axis | Servo motor, type-17 strain wave gear, direct drive |
| Periodic error | ±10 arc-seconds |
| Mount head weight | 5.4 kg |
| Payload capacity | 22–30 kg (without/with counterweight) |
| GoTo speed | 5°/s, maximum 10°/s |
| Saddle | Vixen / Losmandy dual saddle |
| Power input | 12-24 V / 3 A |
| Electronic polar scope support | iPolar / PoleMaster |
| Home position | Mechanical home position |
| Anti-collision system | Dual-axis protection |
| Wedge / altitude-azimuth adjustment | Self-locking wedge with dual azimuth locking and titanium alloy adjustment screws |
| Power-loss braking | RA electromagnetic braking, ≥ 68 N·m |
| Communication | USB, Bluetooth, Wi-Fi, ST4, UMi Mount app |
| Tripod connection | 3/8", M6, CF40 / TC40 compatible |
| Case | Hard case with EVA foam |
| Counterweight shaft thread | M12 |