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IMPORTANT: Our store is located in Canada. All orders that include products manufactured outside of Canada or USA will be subject to tariffs and duties, regardless of the order value. US customers are responsible for all applicable duties and tariffs, and those will be billed by the carrier, except for the Lacerta upgrade kit, for which we collect them at checkout.
IMPORTANT: Our store is located in Canada. All orders that include products manufactured outside of Canada or USA will be subject to tariffs and duties, regardless of the order value. US customers are responsible for all applicable duties and tariffs, and those will be billed by the carrier, except for the Lacerta upgrade kit, for which we collect them at checkout.
OCAL 4.0 Electronic Collimator

OCAL 4.0 Electronic Collimator

by OCAL
SKU OCAL-4
$242.00 - $242.00
$242.00
$242.00 - $242.00
$242.00
Price Match Policy!
  • Precision Electronic Collimator for Newtonians, Ritchey-Chrétien telescopes (and SCT's, with limitations)
  • High-Resolution CMOS Sensor
  • Real-Time Software Feedback on PC, Android, and iOS
  • Included M48 and 1.25" Adapters
  • USB-C Interface with OTG Support
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Manual/Software
  • Warranty

  • Achieve Perfect Collimation with the OCAL Electronic Collimator 4.0

    The OCAL Electronic Collimator 4.0 is a revolutionary tool that replaces subjective guesswork with objective, repeatable, and computer-guided precision for your telescope's optical alignment. By using a high-resolution camera and intelligent software, it allows you to see the alignment of your Newtonian, Ritchey-Chrétien, or SCT optics in real-time on a screen. This system translates tiny mechanical adjustments into clear visual feedback, enabling a level of accuracy that is difficult to achieve with traditional laser or Cheshire collimators.

    For the dedicated astro-imager or discerning visual observer, perfect collimation is not a luxury, it is the foundation of performance. The OCAL 4.0 demystifies this complex process, turning it into a straightforward, guided procedure that can be completed in minutes. The result is consistently sharper stars, higher contrast on planetary details, and images that reflect the true potential of your telescope.

    High-Resolution CMOS Sensor for Data-Driven Alignment

    At the core of the OCAL 4.0 is a sensitive CMOS imaging sensor. Instead of peering through a pinhole, you see a brightly lit, magnified view of your primary and secondary mirrors on your laptop or phone. This clear digital image provides the raw data for the software to analyze, eliminating the ambiguity of the human eye.

    The sensor's resolution allows the software to detect shifts of just a few pixels. This means that an adjustment at the primary mirror that would be imperceptible in a Cheshire eyepiece becomes a clearly visible vector on the screen. You are no longer guessing if you have reached alignment, you are watching it happen with digital certainty.

    Intelligent Collimation Software Guidance

    The real power of the OCAL system is its software, which is compatible with Windows, Android, and iOS devices. The software overlays a series of concentric circles and crosshairs onto the live video feed from the collimator. Your task is simple: adjust your telescope's collimation screws until the reflected optical elements, like the primary mirror's center marking, are perfectly centered within the software's guides.

    This interactive feedback loop removes all interpretation. The red circle aligns with the secondary mirror, the green with the primary, and so on. The software guides you through each step, making the process logical and efficient, even for those new to collimating complex instruments like Ritchey-Chrétien telescopes.

    The Importance of a Precision Mechanical Body

    An electronic collimator is only as good as its ability to sit perfectly parallel to the focuser's optical axis. The OCAL 4.0 features a robust, precisely machined aluminum housing that ensures a tight, repeatable fit. This rigidity is critical, as any slop or tilt in the collimator itself would introduce fundamental errors into the alignment.

    By maintaining a stable mechanical reference point, the OCAL ensures that the alignment you achieve is a true reflection of your telescope's optical path. Each unit undergoes a calibration process to guarantee that the sensor's optical axis is aligned with the housing's mechanical axis, a critical step for accurate results.

    Versatile Connectivity for Field and Observatory Use

    The OCAL 4.0 uses a modern USB-C interface for both power and data, connecting directly to your chosen device. The inclusion of an OTG (On-The-Go) adapter means you are not tied to a bulky laptop. You can run the collimation process from a compatible Android or iOS smartphone or tablet, reducing the amount of gear you need to bring into the field.

    This flexibility is a significant workflow advantage. Whether you are in your backyard or at a dark sky site, you can perform a quick, precise collimation check with the device you already have in your pocket. Setup is as simple as plugging in a single cable.

    Broad Telescope Compatibility with Included Adapters

    The OCAL 4.0 is designed to work with a wide range of telescopes right out of the box. The main body has a standard M42x0.75 (T2) thread, and the package includes two essential adapters: an M42-to-M48 ring and an M42-to-1.25" nosepiece. This combination allows it to be securely mounted in nearly any modern focuser.

    This built-in versatility means you can use the same tool to collimate your fast Newtonian astrograph, your large Dobsonian, or your SCT. The secure, threaded connections of the M42 and M48 adapters provide a more reliable fit than a simple compression ring, further eliminating potential sources of error.

    The OCAL 4.0 Trade-Off: A Necessary Tether

    The primary trade-off for the OCAL's digital precision is the need for a host device. Unlike a standalone laser or Cheshire, the OCAL 4.0 must be connected to a computer, tablet, or phone to function. This means managing an extra piece of equipment and a cable at the telescope, which requires a charged battery and the appropriate software installed.

    For imagers who already use a computer to control their mount and camera, this is a minor integration. However, for purely visual observers who value a minimalist, "grab-and-go" setup, it introduces a digital component to what is traditionally an analog process. The benefit is a level of accuracy that analog tools simply cannot match, but it comes at the cost of simplicity.

  • Will the OCAL 4.0 work with my Ritchey-Chrétien (RC) telescope?

    Yes, the OCAL is an excellent tool for collimating RC telescopes. The software-guided process makes it much easier to align both the secondary and primary mirrors, a task that can be very challenging with traditional tools.

    Will the OCAL 4.0 work with my SCT?

    Yes, but with limitations. While OCAL is a powerful tool for centering the secondary mirror housing and baffle tube, it works differently on an SCT than on a Newtonian.

    Because an SCT uses a spherical secondary mirror, achieving "perfect" visual centering of the reflections in the OCAL software does not always guarantee perfect optical collimation. The physical center of the mirror housing may not perfectly align with the optical axis due to slight mechanical tolerances. For critical performance, OCAL should be used to get the system nearly perfect indoors, but a final star test is always required to fine-tune the tilt of the secondary mirror based on the actual light path.

    Can I use the OCAL 4.0 with my phone instead of a laptop?

    Yes, the OCAL 4.0 is compatible with Android and iOS devices. You will need to download the appropriate OCAL app and use the included OTG adapter to connect the USB cable to your phone or tablet.

    How is the OCAL better than a high-quality laser collimator?

    A laser collimator's accuracy depends on how well it is collimated itself and how perfectly it sits in the focuser. The OCAL is less sensitive to these factors because it analyzes the entire optical system. It measures the actual position of the mirror reflections, not just a single beam, which generally leads to a more accurate and comprehensive alignment.

    Do I need a Barlow lens to use the OCAL with my Newtonian?

    No, you do not need a Barlow lens. The OCAL is inserted directly into the focuser to collimate the secondary mirror and then continues to be used directly for the primary mirror alignment. The software handles all the necessary visuals.

    Is the OCAL difficult to set up for the first time?

    There is an initial learning curve, which involves installing the software and performing a one-time calibration to ensure the OCAL's camera is centered. However, once that is done, subsequent collimation sessions are very fast and straightforward.

  • Product OCAL Electronic Collimator Version 4.0
    Interface USB-C
    System Compatibility Windows 10/11, Android 6+, iOS 12+
    Telescope Connection M42x0.75 (T2) Female Thread
    Included Adapters M42 to M48, M42 to 1.25"
    Weight 134g (4.7 oz)
    • OCAL Electronic Collimator 4.0 Main Unit

      OCAL Collimator Main Unit

      × 1

    • M42 to M48 Adapter Ring

      M42-to-M48 Adapter Ring

      × 1

    • M42 to 1.25-inch Adapter Tube

      M42-to-1.25" Adapter Tube

      × 1

    • USB OTG Adapter

      OTG Adapter

      × 1

    • USB-A to USB-C Data Cable

      USB-A to USB-C Data Cable

      × 1

  • OCAL Warranty Policy