iOptron Electronic Automatic Focuser - iEAF
- 5 kg Maximum Payload Capacity
- High-Precision Stepper Motor Drive
- Built-in Temperature Sensor for Focus Compensation
- ASCOM Compatible for Automated Imaging
- Weighs only 254g
The iOptron Electronic Automatic Focuser (iEAF) automates one of the most critical steps in astrophotography, delivering repeatable, sharp focus across entire imaging sessions. Its high-precision stepper motor handles imaging trains up to 5 kg, while the built-in temperature sensor provides the data needed for software to counteract thermal focus shift. The entire system weighs only 254g and connects via a single USB2.0 port for power and data, eliminating the need for external power supplies or hand controllers.
At the core of the iEAF is a robust stepper motor designed for smooth, precise, and repeatable movements. With a payload capacity of 5 kg, it can easily handle heavy imaging setups that include large-sensor cameras, filter wheels, and off-axis guiders without slipping or backlash. This ensures that once your focusing routine is complete, the focus point remains exactly where it needs to be for the duration of your exposure.
The iEAF is engineered to eliminate focus drift caused by falling nighttime temperatures. A built-in temperature sensor constantly monitors ambient conditions, feeding this data to your imaging software via its ASCOM driver. Programs like N.I.N.A. or SharpCap can then use this information to trigger auto-focus routines automatically, ensuring your stars remain pinpoints from dusk until dawn without manual intervention.
Measuring just 51 x 61 x 41mm and weighing only 254g, the iEAF adds minimal weight and profile to your optical tube, simplifying balancing. For initial setup or manual adjustments in the field, iOptron integrated two direction buttons directly onto the focuser body. This provides immediate, tactile control without needing to connect a separate hand controller or interact with software—a significant convenience for quick adjustments at the telescope.
While the ZWO EAF is a popular choice, the iOptron iEAF presents several key advantages for the astrophotographer.
As the temperature drops overnight, the metal in your telescope tube contracts, causing the focal point to shift. The iOptron iEAF's built-in temperature sensor relays this change to ASCOM-compatible software, which can automatically re-run your autofocus routine. This ensures your images remain critically sharp all night long, preventing hours of data from being ruined by thermal focus drift.
The iOptron iEAF is fully ASCOM compatible, allowing it to work with most major astrophotography control software. It is known to integrate seamlessly with popular applications such as:
Yes, the iOptron iEAF is designed for broad compatibility with most Crayford or Rack-and-Pinion style focusers, which are common on Schmidt-Cassegrains, refractors, and Newtonians. The included bracket and shaft coupler kit is versatile, but you should always confirm the physical layout of your specific focuser to ensure a clear mounting path.
The 5 kg (11 lbs) maximum payload means the iEAF's motor has enough torque to lift a heavy imaging train without stalling or slipping. This is more than sufficient for typical setups including a large astronomy camera, a multi-filter wheel, and an off-axis guider, ensuring reliable and precise focusing performance.
The iOptron iEAF features two small buttons directly on the housing for manual control. One button moves the focuser inward, and the other moves it outward. This allows for quick, tactile adjustments at the telescope for initial focusing without needing to be connected to a computer or fumbling with a separate hand controller.
For a long imaging session on a target like the Andromeda Galaxy (M31), temperatures can drop significantly, causing your telescope to lose focus. The iEAF's built-in temperature sensor and ASCOM integration allow your software to monitor this change and automatically refocus every hour or after a specific temperature drop. This keeps your stars tight and your galactic details sharp across all your subframes without you needing to manually intervene.
| Focuser Compatibility | Crayford or Rack-and-Pinion |
| Drive System | Stepper motor |
| Max Payload | 5 kg |
| Focuser Speed | 3 rpm |
| Control | ASCOM compatible or manual buttons |
| Temperature Sensor | Yes (Built-in) |
| Power / Communication | USB 2.0 |
| Dimensions | 51 x 61 x 41mm |
| Weight | 254g (focuser only) |
The manufacturer has not provided a list of included items for this product.