Precision Autofocusing for Demanding Astrophotography Setups
The Prometheus Astro inFocus Max is a high-torque electronic focuser designed for modern astrophotography systems requiring precision, rigidity and reliability.
Built around a geared stepper motor with a 100:1 reduction system, the inFocus Max is capable of handling heavy imaging trains and stiff focusers while maintaining extremely fine movement resolution for accurate automated focusing.
Designed and assembled in Greece by Prometheus Astro.
Key Features
High Torque Geared Stepper System
The inFocus Max utilizes a geared stepper motor with a 100:1 reduction ratio, delivering exceptional holding torque and smooth micro-adjustments even with heavy imaging setups.
Up to 11kg Payload Capacity
Designed to confidently handle large astrophotography trains including:
- Mono cameras
- Filter wheels
- Off-axis guiders
- Rotators
- Large cooled astronomy cameras
Ultra-Fine Focusing Resolution
With an effective step angle of just 0.075°, the inFocus Max enables highly repeatable and precise autofocus operation for critical imaging applications.
Single USB-C Connection
Power and communication are handled through a single USB-C cable for a cleaner and more reliable setup.
Integrated Environmental Sensors
Built-in sensors provide:
- Temperature readings
- Humidity readings
- Barometric pressure readings
Perfect for autofocus compensation workflows and environmental monitoring.
Broad Compatibility
The inFocus Max uses the popular ZWO EAF mounting pattern and is compatible with existing EAF mounting accessories and brackets.
Lightweight Hybrid Construction
The unit features:
- CNC-machined aluminum front and rear mounting plates
- Lightweight PETG-CF reinforced central body
This design balances rigidity, weight and thermal stability.
Designed for Real Astrophotography Use
The inFocus Max was developed with practical field use in mind:
- Portable imaging rigs
- Permanent observatories
- Remote setups
- Heavy refractors
- Newtonians
- Large imaging trains
Every design decision focused on reliability, simplicity and repeatable autofocus performance under real-world conditions.
Specifications
| Specification | Value |
|---|---|
| Motor Type | Geared Stepper Motor |
| Gear Reduction | 100:1 |
| Maximum Payload | Up to 11kg |
| Effective Step Angle | 0.075° |
| Connection | USB-C |
| Sensor Suite | Temperature, Humidity, Barometric Pressure |
| Mount Compatibility | ZWO EAF mounting pattern |
| Construction | Aluminum front/rear plates, PETG-CF central body |
| Use Case | Astrophotography autofocus |
Pricing
Pre-Order Price
€160 incl. VAT
Future Retail Price
€200 incl. VAT
Availability
Expected availability: June 2026
Pre-orders are now open.
What’s Included
- Prometheus Astro inFocus Max
- USB-C Cable
- Mounting Hardware
- Coupler
- Documentation
Built by Astrophotographers
The inFocus Max was designed from the ground up by active astrophotographers who understand the importance of reliable automation, clean cable management and repeatable focusing performance under the night sky.
