The ESATTO 4" robotic focuser (PrimaLuceLab, SKU: PLLEST4 ) is the largest model in the ESATTO precision focuser family, designed to handle heavy astrophotography setups and telescopes requiring a large free aperture, such as the Takahashi FSQ-106, large refractors or RC tubes. The focuser combines 102.2 mm of free aperture, 35 mm of working travel and a payload capacity of up to 10 kg with a total thickness of only 65 mm . The mechanical resolution of 0.04 µm/step and 40 Crayford ball bearings guarantee backlash-free, repeatable operation even with a heavy camera, filter wheel and corrector.

Key Features of ESATTO 4"

• 102.2 mm free aperture - no vignetting for full frame and medium format cameras
• working travel range of 35 mm with a resolution of 0.04 µm/step
• 10 kg load capacity thanks to the Crayford construction with 40 bearings and a steel strip
• low-profile housing: 65 mm thick (91 mm with optional internal flange)
• USB-C communication and built-in Wi-Fi Virtual HandPad - full remote control via PLAY, ASCOM and INDI
• dedicated ARCO port - direct power supply and control of ARCO 2" or 3" rotators
• status LEDs with dimming function for observatory operation
• PLUS system threads and flanges facilitate the assembly of clamps, plates and PrimaLuceLab accessories

Set components

• ESATTO 4" lift
• USB-C ↔ USB-A cable (150 cm)
• 12 V DC / 5 A mains adapter with 5.5 × 2.5 mm plug
• a set of mounting screws and Allen keys
• user manual

Technical parameters

• free aperture: 102.2 mm
• working travel: 35 mm
• resolution: 0.04 µm/step (160,000 steps/mm)
• body thickness: 65 mm
• axial load capacity: 10 kg
• mechanism type: Crayford + steel strip, 40 bearings
• interfaces: USB-C, Wi-Fi 2.4 GHz, ARCO port
• supply voltage: 12 V DC ( 5.5 × 2.5 mm , center plus) / 0.6 A
• weight: 2.05 kg
• operating temperature range: −25 °C … +40 °C
• manufacturer: PrimaLuceLab – Italy

With its large aperture, high load capacity and submicron precision , ESATTO 4" is the perfect choice for observatories and advanced astrographs, enabling fully automated, repeatable operation even with very heavy camera and accessory sets.