iOptron HEM27EC Hybrid Harmonic Drive Mount With Ipolar And Case

iOptron HEM27EC Hybrid Harmonic Drive Mount with iPolar and Case – Guiding-Optional Precision in a Small Package

iOptron Part Number: H274A

Powerful enough to carry a serious imaging rig—but light enough to ride in your carry-on—the HEM27EC represents a major leap in portable mount design. Weighing just 8.15 lbs, this counterweight-free harmonic mount head supports up to 29.7 lbs of equipment and includes a high-resolution RA encoder, offering real-time periodic error correction accurate enough to make guiding optional for many setups.

For the astrophotographer who wants premium tracking, rock-solid stability, and effortless travel-readiness, the HEM27EC is a mount that doesn’t compromise.

Hybrid Harmonic Design – High Torque, No Backlash

The RA axis of the HEM27EC is driven by a strain wave gear system—also known as a harmonic drive—which eliminates backlash, improves torque efficiency, and delivers silky-smooth tracking. This compact drive system allows for an astonishing 360-second gear period, ideal for long exposures and narrowband imaging.

The DEC axis features a zero-backlash belt-driven worm gear, which offers precise movement, easy balancing, and reliable long-term performance.

Together, these two systems create a responsive, robust drive platform that handles real-world imaging conditions with ease—without needing a traditional counterweight system.

RA Encoder with Real-Time PEC – Guiding Optional

The “EC” in HEM27EC stands for encoder, and it’s the mount’s secret weapon. A high-resolution encoder on the RA axis delivers real-time periodic error correction (RPEC), allowing the mount to self-correct for gear inconsistencies while tracking.

This encoder system offers:

• Accurate unguided imaging for short to mid focal length setups

• Reduced autoguider workload, improving star shapes and efficiency

• No PE training required—corrections happen in real time

For many users imaging at focal lengths under 800mm, guiding can be completely eliminated—cutting down on cables, setup time, and the chance for something to go wrong.

Payload Without the Counterweight

Weighing just 8.15 lbs (3.7 kg), the HEM27EC supports payloads up to 29.7 lbs (13.5 kg)—with no counterweight or shaft required. That makes it one of the highest-performing mounts in the sub-10-pound class.

Whether you're running a fully decked-out 4" refractor, a compact 6" RC, or a wide-field astrograph with multiple accessories, the HEM27EC provides stable, jitter-free tracking that’s rare in mounts this size.

iPolar Alignment Scope – Fast, Reliable, and Included

The HEM27EC comes standard with iOptron’s iPolar electronic polar scope, factory-aligned in the RA axis. This integrated camera system provides fast and accurate polar alignment from anywhere on Earth—even if Polaris is obscured by buildings, trees, or light pollution.

iPolar saves time, increases alignment accuracy, and helps you get to imaging faster—ideal for mobile users who value efficient setup and repeatable results.

GoTo Control and Smart Safety Features

Included with the HEM27EC is the Go2Nova® 8409 hand controller, offering:

• A 212,000+ object database covering deep sky catalogs, solar system objects, double stars, and more

• A cold-resistant OLED display

• Backlit controls for nighttime use

• Built-in Wi-Fi for wireless control via SkySafari or Commander Lite

• USB port for firmware upgrades and PC/Mac control (ASCOM or INDI)

The mount also includes smart operational features like:

• Zero position search and locator for reliable parking/startup

• Friction brakes to safely halt movement in case of power loss

• Power-down memory, so you don’t lose alignment after shutdown

• Cable management system, with no cables hanging off moving parts

Included in the Box

• HEM27EC mount head with high-precision RA encoder

• Integrated iPolar electronic polar scope

• Go2Nova® 8409 hand controller

• Spring-loaded dual saddle (Vixen and Losmandy D-compatible)

• USB and DC power cables

• Soft padded carrying case

• Documentation and two-year manufacturer warranty

Tripod not included. The iOptron 8061A carbon fiber tripod is highly recommended for this mount.

Observing Tip

If you’re using a fast refractor, short focal length astrograph, or imaging lens under 800mm, try running the HEM27EC unguided with a sharp iPolar alignment. You may be surprised how clean your star shapes are without ever launching a guide camera. The encoder does the work—saving you setup time and simplifying your cable tree.

Why Choose the HEM27EC?

The HEM27EC is ideal for serious imagers who travel, automate, or simply want to reduce friction in their observing workflow. With encoder-level tracking, a light but strong frame, and full GoTo and Wi-Fi control, this mount bridges the gap between precision and portability.

It's a mount that truly lets you focus on the sky—not the setup.

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