SESTO SENSO 3 is our most advanced robotic focusing motor for external focusers like Crayford or Rack-and-Pinion

SESTO SENSO 3 is the most advanced robotic focusing motor for external Crayford or Rack-and-Pinion focusers. Built upon the success of the first and second generation motors, the SESTO SENSO 3 adds even more amazing new features, incorporated into a single enclosure to house all the elements that comprise a motorized focusing system:

SESTO SENSO 3 robotic focusing motor for external focusers - main features:

• NEW Compact all-in-one chassis designed to be installed on external Crayford and Rack-and-Pinion focusers
• NEW Integrated encoder for position tracking and manual movement without losing motor position with Automatic Position Recovery option
• NEW Self Centering Clamp 2 (SCC2) for fast installation without brackets or other adapters to focusers with 25mm, 26mm, 33mm and 37mm shafts
• High precision motor with 0.7 micron resolution per step (on focusers with 1:10 reduction)
• 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: 370 gr. (0.8 lbs)

Compact, lightweight and all-in-one design

SESTO SENSO 3 features a compact and lightweight enclosure that houses all control electronics, with ports conveniently located on the side. The unit includes dimmable status LEDs, which can be turned off completely to minimize stray light during nighttime observing or imaging sessions. 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 by using 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 Self Centering Clamp 2 (SCC2)

SESTO SENSO 3 uses the new Self Centering Clamp 2 (SCC2), an evolution of the original SCC system, to easily connect the motor to the shaft of most focusers without the need for external brackets. SCC2 now supports multiple shaft diameters (25mm, 26mm, 33mm, 37mm) allowing for faster installation, and improved mechanical coupling with a wider range of focusers, without the need for other adapters. In fact now SESTO SENSO 3 connects directly to 37mm shafts and, by adding one of the included adapters, can be connected also to 25mm, 26mm, and 33mm diameter shafts. Another advantage of the SCC2 technology is that you can always use the manual (coarse) knobs of your focuser, even if SESTO SENSO 3 is installed, and thanks to the integrated encoder you won’t lose motor position if SESTO SENSO 3 is active. SESTO SENSO 3 is compatible with many telescopes (included bushings: red for 2,5mm diameter, black for 2,8mm diameter, blue for 2,4mm diameter, green for 3,5mm diameter, silver for 3,1mm diameter, gold for 4mm diameter), like (but not limited to these):

SkyWatcher EVOSTAR, EVOLUX and ESPRIT
SkyWatcher Newton and Quattro
Takahashi FSQ85 and FSQ106 with fine focus knob
Baader SteelTrack® focusers
FeatherTouch focusers
GSO Ritchey-Chretien with 2" and 3" focusers
Explore Scientific focusers

Integrated encoder: precise control with freedom of movement

SESTO SENSO 3 integrates a position encoder that tracks the movement of the focuser shaft with extreme accuracy. This allows the user to manually move the focuser, with SESTO SENSO 3 installed and powered on, using the focuser’s original knob without losing motor position. Perfect for users who switch between visual and imaging sessions, this also speeds up and improves the calibration process.

Another advanced feature is the Automatic Position Recovery function, which if enabled automatically restores the previous focus position if focuser movement is detected. This feature is particularly useful in public or educational observatories, where visitors or users may be tempted to manually turn the focuser knob or if the focuser is accidentally moved. Another useful application is when the focuser drawtube shifts under load (please note that SESTO SENSO 3’s encoder is able to detect only shaft movements, not internal focuser slips that cannot be corrected by just the focusing motor but depend on the focuser itself). If you enable this function, you can set a recovery delay (from 0 seconds for instant reaction up to 20 seconds) after which SESTO SENSO 3 automatically moves the focuser drawtube back to its previous position.

USB-C connectivity to control it from a computer

SESTO SENSO 3 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.

Easy control with PLAY astrophotography software

SESTO SENSO 3 integrates perfectly with PLAY, the powerful astrophotography software developed by PrimaLuceLab to simplify and enhance your astrophotography. PLAY provides an intuitive interface that allows you to remotely control the focuser position with precision, directly from your EAGLE or standard Windows 10/11 computer. PLAY unlocks advanced capabilities such as AutoFocus, which automatically analyzes the stars dimensions and adjusts the focuser position for optimal focus position. In addition, PLAY includes features like temperature compensation, focus presets, and real-time status monitoring, making it the ideal solution astrophotographers. 

Advanced control with ASCOM drivers and third party softwares

Thanks to the provided ASCOM driver, SESTO SENSO 3 is fully compatible with a wide range of popular third-party astronomy software, giving you maximum flexibility in how you control your focuser. Whether you’re using applications like NINA, Sequence Generator Pro, MaxIm DL, or others, SESTO SENSO 3 integrates smoothly into your existing workflow. This level of compatibility makes SESTO SENSO 3 an ideal choice for advanced astrophotographers and observatories who demand both performance and software freedom. No matter which platform you prefer, you can count on SESTO SENSO 3 to deliver accurate results night after night.

WiFi connectivity to control it without the need of computer or physical hand pad

SESTO SENSO 3 features a built-in WiFi module that creates its own wireless network, allowing you to control the focuser from any smartphone or tablet—no cables or computer required! Simply connect your device to the SESTO SENSO 3’s WiFi network and launch the built-in Virtual HandPad. You’ll be able to move the focuser using your smartphone or tablet just like you would with a traditional hand controller. Thanks to convenient preset positions, you can easily save and return to specific focus points—perfect for visual observing as well. WiFi control remains active even when SESTO SENSO 3 is connected to a computer, allowing simultaneous control from two devices for added flexibility.

Full compatibility with ARCO rotator

SESTO SENSO 3 features a dedicated port for direct connection to ARCO, the robotic camera rotator and field de-rotator developed by PrimaLuceLab. With ARCO, you can remotely adjust the rotation angle of your camera to achieve perfect framing of your target. If you’re using an alt-azimuth mount, ARCO also allows you to de-rotate the field during long exposures—eliminating the need for an equatorial wedge. SESTO SENSO 3 and ARCO are designed to work seamlessly together, requiring only a single short cable for both power and data. No additional controllers or connections are needed, making it easy to build a compact, fully integrated, and automated imaging system for advanced astrophotography or scientific applications.

DARK mode with dimmable LED indicators

SESTO SENSO 3 is equipped with LED indicators on its body that provide useful visual feedback for device status and diagnostics. The LEDs are fully dimmable, and by enabling DARK mode—via PLAY software or the ASCOM driver—you can turn them off completely to preserve your night vision and eliminate stray light during astrophotography sessions. When using SESTO SENSO 3 with an EAGLE control unit, DARK mode activation can be automated in PLAY: as soon as an imaging sequence starts, all LED lights are automatically switched off, allowing for fully unattended and light-safe operation.

GHOST mode support and firmware updates

When used with an EAGLE control unit, SESTO SENSO 3 supports GHOST mode, allowing complete operation without needing a USB cable, for a cleaner setup. GHOST mode also acts as a backup communication channel: if the USB cable stops working, you can still access SESTO SENSO 3 through the EAGLE and continue your imaging session without interruption. In addition, firmware updates can be easily installed via PLAY software, ensuring your focuser always benefits from the latest features, improvements, and compatibility enhancements.

Temperature sensor port for optional external probe

SESTO SENSO 3 supports temperature compensation when used with the optional external temperature probe, allowing calculation of how the focus position shifts as ambient temperature changes throughout the night. Once the probe is connected, you can perform a temperature calibration directly in PLAY to determine the correlation between temperature and focus shift. After calibration, temperature compensation can be applied automatically by PLAY or by third-party software via the ASCOM driver, ensuring stable focus during long imaging sessions—even with very fast focal ratio telescopes (for example faster than f3) and in fluctuating environmental conditions.

SESTO SENSO 3: dimensions and weight

SESTO SENSO 3 includes all these advanced features in a lightweight, compact all-in-one chassis designed to be installed on your focuser without the need of external brackets. SESTO SENSO 3 weights just 370 gr. (0.8 lbs). See image below for product dimensions.

SESTO SENSO 3 SC is our most advanced robotic focusing motor for SC type telescopes with internal focuser

SESTO SENSO 3 SC is our most advanced robotic focus motor for SC type telescopes with internal focusers like Celestron Schmidt-Cassegrain (6” to 14”), EdgeHD (8", 11" and 14"), RASA (8” to 14”) and SkyWatcher MAK180. Built upon the success of the first and second generation motors, the SESTO SENSO 3 SC adds even more incredible new features, incorporated into a single enclosure housing all the elements that comprise a motorized focusing system:

SESTO SENSO 3 SC robotic focusing motor for SC type telescopes - main features:

• NEW Compact all-in-one chassis designed to be installed on SC type telescopes with internal focusers
• NEW Integrated encoder for position tracking and manual movement without losing motor position with Automatic Position Recovery option
• NEW Direct Pulley Clamp (DPC) with backlash-free, pulley-driven coupling for precise motorized focusing and manual adjustment
• High resolution motor with 2 million steps for precise control of internal mirror focusers
• 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: 440 gr. (1.0 lbs)

Compact, lightweight and all-in-one design

SESTO SENSO 3 SC features a compact and lightweight enclosure that houses all control electronics, with ports conveniently located on the side. The unit includes dimmable status LEDs, which can also be turned off completely to minimize stray light during nighttime observing or imaging sessions. 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 by using 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 Direct Pulley Clamp (DPC)

SESTO SENSO 3 SC features the new Direct Pulley Clamp, specifically designed for telescopes with internal mirror focusing mechanisms such as Celestron Schmidt-Cassegrain (6” to 14”), EdgeHD (8", 11" and 14"), RASA (8” to 14”) and SkyWatcher MAK180. This innovative pulley-based design eliminates mechanical backlash and ensures smooth, precise motorized focusing. It also allows manual focusing at any time using the telescope’s knob, while the integrated encoder always keeps track of the focuser’s position – even after manual adjustments. Thanks to the adapters included in the package, SESTO SENSO 3 SC is compatible with many telescopes like (but not limited to these):

Celestron Schmidt-Cassegrain 6” to 14"
Celestron EdgeHD Aplanatic SC 8” to 14" (except EdgeHD 9.25") 
Celestron RASA 8” to 14"
SkyWatcher MAK180PRO

Integrated encoder: precise control with freedom of movement

SESTO SENSO 3 SC integrates a high-precision position encoder that continuously monitors the motor shaft, even when the focus is adjusted manually with the provided knob in the Direct Pulley Clamp. This allows full freedom of movement while maintaining accurate position tracking — ideal for telescopes with internal mirror focusing systems like Schmidt-Cassegrain, EdgeHD, or RASA. Whether you’re switching between visual and imaging setups or simply need to make manual adjustments, SESTO SENSO 3 SC ensures that the focus position is always known and reliable.

A key feature exclusive to SESTO SENSO 3 SC is the Automatic Calibration mode, which works in synergy with the integrated encoder to automatically detect the minimum and maximum travel positions of your SC-type focuser. This makes SESTO SENSO 3 SC an ideal solution even for remote observatories, since you can calibrate the focuser remotely without manual intervention — a capability not available in other SESTO SENSO 3 models. Please note that the encoder tracks motor shaft rotation only and cannot detect focus shifts caused by mirror flop or internal mechanical play. Another advanced feature is the Automatic Position Recovery function, which if enabled automatically restores the previous focus position if focuser movement is detected. This is especially useful in public or educational observatories, where users may manually turn the focuser knob, or if the focuser is accidentally moved. When this function is enabled, you can set a customizable recovery delay (from 0 seconds for instant reaction up to 20 seconds) before SESTO SENSO 3 SC returns to the previous focuser position.

USB-C port for fast and reliable computer control

SESTO SENSO 3 SC includes a USB-C port that allows easy and direct connection to your Windows 10/11 PC or to the EAGLE computer. Compared to older USB standards, USB-C offers key advantages: the reversible plug simplifies connections in the dark, while the robust physical interface helps prevent accidental disconnections — ideal for both portable setups and permanent observatories. Thanks to full compatibility with widely available USB-C cables, you can seamlessly integrate SESTO SENSO 3 SC into your astrophotography system without relying on special or proprietary connectors.

Seamless integration with PLAY astrophotography software

SESTO SENSO 3 SC 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 presets, 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 popular astrophotography softwares

SESTO SENSO 3 SC 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 SC is built to meet the needs of demanding imaging sessions, night after night.

Wireless control via built-in WiFi and Virtual HandPad

With integrated WiFi functionality, SESTO SENSO 3 SC lets you operate your focuser wirelessly—no need for a computer or physical hand controller. The device generates its own WiFi 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 SC 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 SC 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 and adjustable LED brightness

SESTO SENSO 3 SC 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 connectivity and easy firmware upgrades

SESTO SENSO 3 SC 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 SC up to date with the latest features, performance enhancements, and compatibility improvements.

Temperature sensor port for automatic focus compensation

SESTO SENSO 3 SC 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.

SESTO SENSO 3 SC: dimensions and weight

SESTO SENSO 3 SC maintains a compact and lightweight form factor that mounts directly onto your telescope. Weighing only 440 gr. (1.0 lbs), it adds minimal load to your setup while delivering high performance. Refer to the image for detailed dimensions and see how easily SESTO SENSO 3 SC integrates with your telescope.

SESTO SENSO 3 LS is our most advanced robotic focusing motor for telephoto photographic lenses

Built upon the success of the first and second generation motors, the SESTO SENSO 3 LS adds exclusive features specifically designed for imaging with photographic lenses, incorporated into a single enclosure to house all the elements that comprise a motorized focusing system for astrophotography.

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 (1.1 lbs)

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.

SESTO SENSO 3 LS: dimensions and weight

SESTO SENSO 3 LS includes all these advanced features in a lightweight, compact all-in-one chassis specifically designed to be installed on telephoto lenses without the need for external brackets or adapters. SESTO SENSO 3 LS weighs just 515 grams (1.1 lbs). In the picture you can see the dimensions.