SESTO SENSO 3 LS robotic focusing motor for telephoto lenses

SESTO SENSO 3 LS robotic focusing motor for telephoto lenses - main features:

• NEW Compact all-in-one chassis designed to be used with telephoto photographic lenses (Canon, Nikon, and others)
• NEW Integrated encoder for position tracking and manual movement without losing motor position, with Automatic Position Recovery option
• NEW Lens Gear Clamp (LGC) with backlash-free, gear-driven coupling for precise motorized focusing of photographic lenses without external belts
• High resolution motor with 2 million steps for precise control manual focuser of telephoto lenses
• USB-C connectivity to control from computers with astronomy software
• WiFi connectivity to control it from smartphone or tablet with the included Virtual HandPad, without the need of computer or physical hand pad
• Compatible with PLAY software to control focus position, also with autofocus
• Provided with ASCOM drivers to let you control through third party astronomy software
• ARCO rotator port to directly connect the ARCO without the need for additional data or power cables
• DARK mode with dimmable LED lights, that can even be turned off completely
• GHOST mode to remove USB cable when used with EAGLE computer
• Temperature sensor port to automatically compensate focus caused by environmental temperature change
• Developed and manufactured in Italy
• Weight: 515 grams

Compact, lightweight and all-in-one design

SESTO SENSO 3 LS features a compact and lightweight enclosure that integrates all control electronics, with all ports conveniently located on the side. The unit includes dimmable status LEDs, which can also be turned off completely to avoid stray light during nighttime imaging sessions with photographic lenses. Connectivity is streamlined and efficient: a USB-C port allows connection to an EAGLE or any Windows® computer using the included USB cable; the dedicated ARCO port enables both power and control of an optional ARCO camera rotator through a single cable; the 12V power port (5.5/2.5mm, center-positive) supplies power to both the motor and internal electronics using the included cigarette lighter-style cable (or with an optional cable for direct connection to the EAGLE); and a temperature sensor port lets you connect the optional probe for use with third-party software that supports automatic focus compensation based on ambient temperature changes.

Easy installation with Lens Gear Clamp (LGC)

SESTO SENSO 3 LS features the new Lens Gear Clamp (LGC), specifically designed for telephoto photographic lenses such as Canon, Nikon, and other models with manual focus rings. This innovative gear-based design eliminates mechanical backlash and ensures smooth, precise motorized focusing without the need for external belts. The integrated rubber gear directly engages the lens focus ring, while the Arca-Swiss style mount allows you to secure SESTO SENSO 3 LS to a PLUS Vixen-style dovetail bar for perfect alignment. Manual focusing is still possible at any time by rotating the lens’s focus ring, while the integrated encoder keeps track of the motor’s position—even after manual adjustments. This makes SESTO SENSO 3 LS ideal for astrophotographers who want the precision of a robotic focusing motor combined with the freedom of manual control.

If your telephoto lens does not include an L-bracket with photo thread for mounting to the PLUS Vixen-style dovetail bar, we offer an optional Secondary Support for Photo Lenses—a dedicated accessory that ensures proper stability and alignment when using SESTO SENSO 3 LS.

To provide optimal grip on different lens focus rings, SESTO SENSO 3 LS comes with two interchangeable rubber gears: one for lenses with focus rings up to 18mm in width, and one for lenses with focus rings thicker than 18mm. This ensures maximum contact and precision across a wide range of compatible lenses. SESTO SENSO 3 LS is compatible with many photographic lenses, such as (but not limited to):

• Nikkor Z 70-200mm f/2.8 Vr S
• Nikkor Z 100-400mm f/4.5-5.6 VR S
Nikkor Z 24-120mm f/4 S
Nikkor Z 24-70mm f/4 S
• And other telephoto lenses with manual focus ring

Integrated encoder: precise control with freedom of movement

SESTO SENSO 3 LS integrates a high-resolution position encoder that tracks the movement of the motor shaft with extreme accuracy. This allows the user to manually rotate the focus ring of the photographic lens, with SESTO SENSO 3 LS installed and powered on, without losing the motor’s reference position. Ideal for astrophotographers who need to fine-tune focus manually before switching to fully automated control, this feature also improves the initial calibration process.
Another advantage of the integrated encoder is its ability to detect and compensate for small shifts in focus caused by lens mechanics. With this Automatic Position Recovery function, SESTO SENSO 3 LS can also automatically move the lens focus ring back to the previous position if it is rotated manually or accidentally shifted. You can define a recovery delay (from 0 seconds for instant reaction up to 20 seconds). Please note that the encoder detects motor shaft movements only and cannot account for internal mechanical slips in the lens focusing mechanism.

USB-C connectivity to control it from a computer

SESTO SENSO 3 LS features a modern USB-C port for direct connection to your control device, whether it’s a standard Windows 10 or 11 PC or the EAGLE computer. The USB-C interface offers a range of benefits over traditional USB connections: it’s reversible, making it easy to plug in even in low-light conditions, and it ensures a secure and reliable connection that’s resistant to accidental disconnections—especially useful in mobile or remote observatory setups. Plus, the wide compatibility with standard USB-C cables makes it easy to integrate SESTO SENSO 3 into any modern astrophotography workflow without the need for proprietary connectors.

Seamless integration with PLAY astrophotography software

SESTO SENSO 3 LS is fully compatible with PLAY, the astrophotography software developed by PrimaLuceLab to make astrophotography easier and more effective. With its user-friendly interface, PLAY lets you precisely manage the focuser remotely from your EAGLE computer or any Windows 10/11 PC. The software includes powerful tools like AutoFocus, which evaluates star sharpness and automatically adjusts focus to achieve perfect image clarity. Additional features such as temperature compensation, customizable focus pre-sets, and real-time monitoring ensure accurate and consistent focusing throughout your imaging session — making PLAY the ideal companion for astrophotographers.

Full compatibility with ASCOM drivers and third party software

SESTO SENSO 3 LS supports the ASCOM standard, allowing seamless integration with many leading third-party astronomy applications. Whether you prefer using NINA, Sequence Generator Pro, MaxIm DL, or other programs, this focuser adapts perfectly to your setup. Its broad software compatibility gives astrophotographers and research observatories the freedom to use their preferred tools without compromise. With reliable performance and precise control across different applications, SESTO SENSO 3 LS is built to meet the needs of demanding imaging sessions, night after night.

Wireless control via built-in WiFi and Virtual HandPad

With integrated Wi-Fi functionality, SESTO SENSO 3 LS lets you operate your focuser wirelessly—no need for a computer or physical hand controller. The device generates its own Wi-Fi network, so you can connect directly using a smartphone or tablet and access the Virtual HandPad through your browser. This intuitive interface allows you to move the focuser with ease and even store custom focus positions for quick recall, making it ideal for both imaging and visual observation. Virtual HandPad control stays active even when the unit is connected to a computer, giving you flexible dual-control options from multiple devices.

Direct integration with ARCO rotator

SESTO SENSO 3 LS includes a dedicated port that allows a direct connection to ARCO, the high resolution camera rotator and field de-rotator developed by PrimaLuceLab. This lets you control your camera’s rotation remotely for accurate target framing, or apply automatic field de-rotation when using alt-azimuth mounts—removing the need for equatorial wedges during long exposures. SESTO SENSO 3 LS and ARCO are engineered to work perfectly integrate, using just one compact cable for both data and power. This streamlined setup simplifies your imaging train and enables the creation of a fully automated, compact, and high-performance astrophotography system.

DARK mode with dimmable LED indicators

SESTO SENSO 3 LS features onboard LED indicators that offer clear visual cues about the device’s activity and status. To support light-sensitive environments, the LED brightness can be finely adjusted—or completely turned off—by enabling DARK mode through the PLAY software or ASCOM driver. This helps protect your night vision and eliminates unwanted illumination during imaging. When paired with an EAGLE control unit, DARK mode can be triggered automatically: as soon as an acquisition sequence begins in PLAY, the system disables all LEDs to ensure a fully automated and light-controlled astrophotography session.

GHOST mode support and easy firmware updates

SESTO SENSO 3 LS takes full advantage of GHOST mode when paired with an EAGLE computer, allowing you to operate the focuser without a USB cable—perfect to simplify your setup. GHOST mode also acts as a fail-safe communication path: if the USB link is lost, the EAGLE can maintain control of the focuser so you can continue imaging without disruption. Plus, thanks to seamless integration with PLAY software, you can easily install firmware updates, keeping your SESTO SENSO 3 LS up to date with the latest features, performance enhancements, and compatibility improvements.

Temperature sensor port for optional external probe

SESTO SENSO 3 LS includes a dedicated port for an optional temperature sensor, enabling dynamic focus compensation based on ambient temperature variations during the night. By connecting the optional probe and running a calibration in the PLAY software, you can define how temperature affects focus position. Once this correlation is established, compensation can be applied automatically by PLAY or third-party applications via the ASCOM driver. This is especially valuable when using fast optical systems (e.g. faster than f/3), or in environments where temperature shifts significantly throughout your imaging session.