Astronomy Specialist


$1,099.00 AUD

Prima Luce Lab


Click here for instructions on how to install the ESATTO to refractor telescopes.

ESATTO is the new robotic focuser with a 5kg payload capacity and an incredible resolution of 0.04 micron per step. It can be controlled via USB cable on any Windows computer or via Wi-Fi using a smartphone or tablet. 

ESATTO 2" has a 51mm free aperture, 15mm of draw tube excursion and communicates directly to the ARCO camera rotator. It is designed for astrophotography but it also works extremely well for visual use. 

Prima Luce Lab Esatto

 ESATTO 2” robotic microfocuser - main features:

  • Crayford style focuser with 18 ball bearings, specially designed for very high load capacity (up to 5kg) with no flexure
  • Low profile design with an optical thickness of only 67mm
  • 15mm focuser travel with an incredible resolution of 0.04 microns per step!
  • Special adapters to easily connect it to many different telescopes
  • It can be directly controlled by EAGLE or any Windows computer with dedicated control software or ASCOM drivers
  • USB-C connector
  • Wi-Fi capability from any smartphone, tablet or computer
  • ESATTO Virtual HandPad app for visual use
  • Many camera threaded adapters with stop ring on the camera side to rotate the camera to the desired angle
  • ARCO port to easily connect the ARCO camera rotator without the need for additional data or power cables
  • Weight: 835g

Designed to offer the best performance for astrophotography

The special Crayford design with 18 ball bearings allows ESATTO 2” to have an impressive 5kg payload capacity with the focusing smoothness that is required by modern astrophotography techniques (eg. autofocusing with V-curve). ESATTO 2” has a draw tube with 51mm of free aperture and 15mm of travel.


Many adapters available 

You do not need to worry about how to connect ESATTO to your telescope as there are many adapters available. You can easily connect ESATTO 2” to telescopes like Schmidt-Cassegrains, Aplanatic Schmidt-Cassegrains, refractors, Cassegrains, Newtonians and more. ESATTO truly is the universal focuser and if you cannot find an adapter for your telescope, just contact us.



Designed for remote control via USB-C port from the EAGLE or from any Windows computer with a standard USB port

ESATTO has been specifically designed for remote operations. It uses a sturdy USB-C port to communicate with your computer but also for power supply. The USB port of your computer has to supply at least 1 Ampere to supply ESATTO. All the USB 3.0 ports of EAGLE supply 1 Ampere so you will only need one USB cable to power and control ESATTO.

Designed for remote control via Wi-Fi, from any smartphone, tablet or computer via the ESATTO Virtual HandPad app

ESATTO has a built-in Wi-Fi connection for remote control so you can operate it from any smartphone, tablet or computer. Just connect your device to the Wi-Fi network of ESATTO and start the Virtual Hand Pad through your browser. Its convenient preset settings allows to record and move the focuser to specific predetermined positions. The Wi-Fi control works even if ESATTO is connected to a computer so you can control it simultaneously from 2 devices.

Focuser draw tube with M56 x 1 thread and stop ring for a perfect camera connection

To avoid any camera tilt or optical train flexure, ESATTO 2" has a M56 x 1 male thread where you can screw on an adapter for your camera or accessory. The optional 2" visual back is generally only used for visual observations. The stop ring allows to lock the camera at a precise angle to better frame the object.

Connection with a single cable to ARCO

ESATTO includes a special port for ARCO, the robotic camera rotator.  With ARCO you can remotely control the rotation angle of your camera to achieve perfect framing of the object. ESATTO and ARCO are designed to work together as you will only need one short connector between the two!





5 kg

Clear aperture

51 mm


0.04 micron / step

Draw tube excursion

15 mm

Thread on camera side

M56 x 1 male


835 gr


94 mm x 115.6 mm x 64.2 mm 





  • Prima Luce Lab Esatto 2"
  • Power supply cable
  • USB-C cable



ZWO camera software Manual (English)

ZWO camera software Manual (Italian)

ZWO camera software Drivers

ZWO camera software Esatto useful articles



To have access to the latest version of the manual, software package and firmware visit 


To connect Esatto via WiFi to your computer, smartphone or tablet and use the virtual hand pad: 

  • Connect your device to the focuser WiFi network ESATTOxxxxx;
  • Enter the password "primalucelab", 
  • Open your browser and enter the address

    Customer Reviews

    Based on 3 reviews
    David Maguire

    Bought the 2" Esatto/Arco combination .. Excellent communication and assistance as usual from the team at Testar .. from a Toolmakers perspective Prima Luca components are beautifully made .. design and assembly to my Saxon 102mm scope was straight forward (made a dedicated adapter) camera end was off the shelf spacers etc ... running the setup through N.I.N.A. and everything configured easily and sequences run spot on .. just need less cloudy skies in MELB.

    John Connor
    Terrific focuser

    This is a terrific focuser. I'm using it with a 9.25 EdgeHD SCT. Not only does it carry a heavy load and allow unattended refocusing during the night but it does a measurably better job than I was ever able to achieve with a bahtinov mask.

    I use it with a wired usb connection to NINA, as I have never had reliable result with wifi. Note that the Esatto is so precise (small stepsize) that you will need to user a large stepsize in NINA. I started with 1000 and now use 1500.

    One quibble - you have to intall Primaluce's free astro imaging program to update the firmware, but that took 5 mins and gives you another way to control the focuser, so that's ok.

    I like this thing so much I have now bought the Esatto 3 upgrade kit for my Esprit 100 - looking forward to trying it out.

    Anssi Pitkanen
    Best focuser I've had

    Esatto 2 moves quickly, quantifies the focuser position, has programmable presets that you can use for instance to narrow down to optimal focus, and eliminates focuser shift and the vibration from touching your focuser - and thus the telescope.

    Together these qualities makes it very fast to assess overall seeing conditions, find sub-seeing focus - where the clear image will appear once those brief moments of still seeing occur - and to refocus for your camera, particularly with the help of your devices own focuser helpers, like FWHM and the brightest pixel. Very helpful on filter change and to check focus over the course of the night.



    $1,099.00 AUD

    Optical design

    Image circle

    Focal ratio


    Focal length

    Optical thickness



    Colour or Mono

    Pixel size

    Sensor dimensions


    Sensor diagonal

    Quantum efficiency

    Read noise

    Fullwell capacity

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    Camera backfocus

    Filter size

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    Bandpass (FWHM)

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    Payload capacity

    Latitude range

    Dovetail saddle

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    Periodic error correction

    Counterweight shaft

    Azimuth adjustment range

    Internal diameter

    Illuminated diameter

    Compatible telescope external diameter





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