PrimaLuceLab SESTO SENSO 3 Robotic Focusing Motor for External Focusers
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- Integrated Encoder with Automatic Position Recovery: allows you to manually use the focuser knob without losing motor position.
- Wireless and USB-C Connectivity: control the focuser remotely via computer or smartphone/tablet.
- Self-Centering Clamp 2 (SCC2) System: enables fast, bracket-free installation on focusers with 25 mm, 26 mm, 33 mm, or 37 mm shafts.
- High-Precision Motor with Temperature Compensation: offers 0.7 micron step control (with 1:10 reduction) and supports automatic adjustments for temperature changes.
PrimaLuceLab SESTO SENSO Robotic Focusing Motor
The PrimaLuceLab SESTO SENSO 3 is the most advanced robotic focusing motor for external rack-and-pinion or Crayford-style focusers; combining high precision, flexibility, and ease of use in a compact design. Developed and manufactured in Italy, it introduces key innovations such as the integrated position encoder, which allows manual movement of the focuser without losing motor position with Automatic Position Recovery option, and the new Self Centering Clamp 2 (SCC2) for fast installation to many focusers without external brackets or adapters.
With USB-C and built-in WiFi connectivity, you can control SESTO SENSO 3 from your computer or wirelessly via the Virtual HandPad using a smartphone or tablet. Its high-precision motor delivers 0.7 micron per step resolution, making it ideal for both visual observation and astrophotography!
SESTO SENSO 3 Key Features
- Compact all-in-one chassis designed to be installed on external Crayford and Rack-and-Pinion focusers
- Integrated encoder for position tracking and manual movement without losing motor position with Automatic Position Recovery option
- 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
- Weight: 0.8 lb (370 g)
Check out these videos below of the SESTO SENSO 3 in action!
Lets Dive Deeper
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 features the new SCC2 system, allowing quick, bracket-free connection to most focuser shafts (25 mm, 26 mm, 33 mm, 37 mm) using included adapters. It supports direct use of the focuser’s manual knobs without losing motor position thanks to its integrated encoder. Compatible with a wide range of telescopes and focusers—including SkyWatcher EVOSTAR/EVOLUX/ESPRIT, Takahashi FSQ85/FSQ106, Baader SteelTrack®, FeatherTouch, GSO Ritchey-Chrétien, and Explore Scientific—SCC2 makes installation fast, flexible, and reliable. Including, but not limited to:
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 in and 3 in focusers
Explore Scientific focusers
Integrated encoder: precise control with freedom of movement
SESTO SENSO 3 features an integrated position encoder that precisely tracks focuser shaft movement, allowing manual use of the original focuser knob without losing motor position—ideal for switching between visual and imaging sessions and speeding up calibration. Its Automatic Position Recovery function can restore the previous focus position if the focuser is moved, useful in public observatories or if the drawtube shifts under load. Users can set a recovery delay from 0 to 20 seconds for instant or gradual correction. (Note: the encoder detects shaft movement only; internal focuser slips cannot be corrected by the motor.)
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 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.
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 f/3 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.
Specifications:
- External Focuser: rack-and-pinion or Crayford-style
-
Motor resolution: 0.7 microns per step (with 1:10 reduction)
-
Weight: 370 g (0.8 lb)
-
Compatible focuser shaft diameters (via Self Centering Clamp 2): 25 mm, 26 mm, 33 mm, 37 mm
-
Connectivity: USB‑C port for computer control, built‑in WiFi for smartphone/tablet control
-
Ports include: 12 V power input, temperature sensor port, ARCO rotator port
-
Operating modes/features: DARK mode (dimmable/turn‑off LEDs), GHOST mode when paired with EAGLE computer
Other Information
- Country of Manufacture: Italy
PrimaLuceLab SESTO SENSO Robotic Focusing Motor
The PrimaLuceLab SESTO SENSO 3 is the most advanced robotic focusing motor for external rack-and-pinion or Crayford-style focusers; combining high precision, flexibility, and ease of use in a compact design. Developed and manufactured in Italy, it introduces key innovations such as the integrated position encoder, which allows manual movement of the focuser without losing motor position with Automatic Position Recovery option, and the new Self Centering Clamp 2 (SCC2) for fast installation to many focusers without external brackets or adapters.
With USB-C and built-in WiFi connectivity, you can control SESTO SENSO 3 from your computer or wirelessly via the Virtual HandPad using a smartphone or tablet. Its high-precision motor delivers 0.7 micron per step resolution, making it ideal for both visual observation and astrophotography!
SESTO SENSO 3 Key Features
- Compact all-in-one chassis designed to be installed on external Crayford and Rack-and-Pinion focusers
- Integrated encoder for position tracking and manual movement without losing motor position with Automatic Position Recovery option
- 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
- Weight: 0.8 lb (370 g)
Check out these videos below of the SESTO SENSO 3 in action!
Lets Dive Deeper
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 features the new SCC2 system, allowing quick, bracket-free connection to most focuser shafts (25 mm, 26 mm, 33 mm, 37 mm) using included adapters. It supports direct use of the focuser’s manual knobs without losing motor position thanks to its integrated encoder. Compatible with a wide range of telescopes and focusers—including SkyWatcher EVOSTAR/EVOLUX/ESPRIT, Takahashi FSQ85/FSQ106, Baader SteelTrack®, FeatherTouch, GSO Ritchey-Chrétien, and Explore Scientific—SCC2 makes installation fast, flexible, and reliable. Including, but not limited to:
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 in and 3 in focusers
Explore Scientific focusers
Integrated encoder: precise control with freedom of movement
SESTO SENSO 3 features an integrated position encoder that precisely tracks focuser shaft movement, allowing manual use of the original focuser knob without losing motor position—ideal for switching between visual and imaging sessions and speeding up calibration. Its Automatic Position Recovery function can restore the previous focus position if the focuser is moved, useful in public observatories or if the drawtube shifts under load. Users can set a recovery delay from 0 to 20 seconds for instant or gradual correction. (Note: the encoder detects shaft movement only; internal focuser slips cannot be corrected by the motor.)
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 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.
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 f/3 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.
Specifications:
- External Focuser: rack-and-pinion or Crayford-style
-
Motor resolution: 0.7 microns per step (with 1:10 reduction)
-
Weight: 370 g (0.8 lb)
-
Compatible focuser shaft diameters (via Self Centering Clamp 2): 25 mm, 26 mm, 33 mm, 37 mm
-
Connectivity: USB‑C port for computer control, built‑in WiFi for smartphone/tablet control
-
Ports include: 12 V power input, temperature sensor port, ARCO rotator port
-
Operating modes/features: DARK mode (dimmable/turn‑off LEDs), GHOST mode when paired with EAGLE computer
- SESTO SENSO 3
- 25mm, 26mm, 33mm shaft adapters (it connects to 37mm shaft without adapters)
- 6 color-keyed bushings for different focuser types
- USB-C to standard USB-A cable
- 12v DC cigarette-style plug power cable
- Hex keys for assembly
- Quick installation guide
- Integrated Encoder with Automatic Position Recovery: allows you to manually use the focuser knob without losing motor position.
- Wireless and USB-C Connectivity: control the focuser remotely via computer or smartphone/tablet.
- Self-Centering Clamp 2 (SCC2) System: enables fast, bracket-free installation on focusers with 25 mm, 26 mm, 33 mm, or 37 mm shafts.
- High-Precision Motor with Temperature Compensation: offers 0.7 micron step control (with 1:10 reduction) and supports automatic adjustments for temperature changes.
PrimaLuceLab SESTO SENSO Robotic Focusing Motor
The PrimaLuceLab SESTO SENSO 3 is the most advanced robotic focusing motor for external rack-and-pinion or Crayford-style focusers; combining high precision, flexibility, and ease of use in a compact design. Developed and manufactured in Italy, it introduces key innovations such as the integrated position encoder, which allows manual movement of the focuser without losing motor position with Automatic Position Recovery option, and the new Self Centering Clamp 2 (SCC2) for fast installation to many focusers without external brackets or adapters.
With USB-C and built-in WiFi connectivity, you can control SESTO SENSO 3 from your computer or wirelessly via the Virtual HandPad using a smartphone or tablet. Its high-precision motor delivers 0.7 micron per step resolution, making it ideal for both visual observation and astrophotography!
SESTO SENSO 3 Key Features
- Compact all-in-one chassis designed to be installed on external Crayford and Rack-and-Pinion focusers
- Integrated encoder for position tracking and manual movement without losing motor position with Automatic Position Recovery option
- 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
- Weight: 0.8 lb (370 g)
Check out these videos below of the SESTO SENSO 3 in action!
Lets Dive Deeper
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 features the new SCC2 system, allowing quick, bracket-free connection to most focuser shafts (25 mm, 26 mm, 33 mm, 37 mm) using included adapters. It supports direct use of the focuser’s manual knobs without losing motor position thanks to its integrated encoder. Compatible with a wide range of telescopes and focusers—including SkyWatcher EVOSTAR/EVOLUX/ESPRIT, Takahashi FSQ85/FSQ106, Baader SteelTrack®, FeatherTouch, GSO Ritchey-Chrétien, and Explore Scientific—SCC2 makes installation fast, flexible, and reliable. Including, but not limited to:
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 in and 3 in focusers
Explore Scientific focusers
Integrated encoder: precise control with freedom of movement
SESTO SENSO 3 features an integrated position encoder that precisely tracks focuser shaft movement, allowing manual use of the original focuser knob without losing motor position—ideal for switching between visual and imaging sessions and speeding up calibration. Its Automatic Position Recovery function can restore the previous focus position if the focuser is moved, useful in public observatories or if the drawtube shifts under load. Users can set a recovery delay from 0 to 20 seconds for instant or gradual correction. (Note: the encoder detects shaft movement only; internal focuser slips cannot be corrected by the motor.)
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 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.
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 f/3 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.
Specifications:
- External Focuser: rack-and-pinion or Crayford-style
-
Motor resolution: 0.7 microns per step (with 1:10 reduction)
-
Weight: 370 g (0.8 lb)
-
Compatible focuser shaft diameters (via Self Centering Clamp 2): 25 mm, 26 mm, 33 mm, 37 mm
-
Connectivity: USB‑C port for computer control, built‑in WiFi for smartphone/tablet control
-
Ports include: 12 V power input, temperature sensor port, ARCO rotator port
-
Operating modes/features: DARK mode (dimmable/turn‑off LEDs), GHOST mode when paired with EAGLE computer
Other Information
- Country of Manufacture: Italy
- SESTO SENSO 3
- 25mm, 26mm, 33mm shaft adapters (it connects to 37mm shaft without adapters)
- 6 color-keyed bushings for different focuser types
- USB-C to standard USB-A cable
- 12v DC cigarette-style plug power cable
- Hex keys for assembly
- Quick installation guide
PrimaLuceLab SESTO SENSO 3 Robotic Focusing Motor for External Focusers