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Explore Scientific  |  SKU: ES-FOC3

Explore Scientific 3-inch Self-Centering Focuser

$949.99 $1,139.99

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Explore Scientific 3-inch Self-Centering Focuser

Revolutionize Your Astrophotography with the Explore Scientific 3-Inch Self-Centering Focuser

Unlock the full potential of your astrophotography with the Explore Scientific 3-Inch Self-Centering Focuser. Engineered for unparalleled stability, precision, and smooth operation, this focuser is the cornerstone of any serious astrophotographer's setup. Weighing in at 5.7 pounds, its robust construction supports heavy imaging trains effortlessly, ensuring your celestial captures are nothing short of extraordinary.

Key Features:

  • Precision Engineered for Stability: The innovative self-centering compression system exerts uniform pressure across the draw tube, ensuring a secure, stable connection that eradicates flex, tilt, and image shift. This guarantees crisp, clear images across all your astrophotography ventures.
  • Smooth, Precision Focusing: Experience the seamless glide of the draw tube, facilitated by a helical rack-and-pinion system enriched with marine-grade PTFE silicone. This design minimizes backlash and allows for precise adjustments, enhancing your focus on celestial wonders.
  • Superior Light Management: With a 3-inch diameter interior draw tube lined with multiple baffles, this focuser significantly reduces internal reflections. This feature is crucial for capturing the rich details of the night sky without compromising on quality.
  • Heavy-Duty Lifting Capacity: Designed to handle up to 17 pounds, this focuser accommodates a wide range of imaging accessories without breaking a sweat. Its locking clutch system and 9:1 focus mechanism with stainless-steel ball bearings and a stainless-steel focus shaft ensure that your setup remains firmly in place, even when fully extended. The draw tube has a travel of 84.5mm.
  • Designed for Convenience: This focuser's compatibility with popular electric focuser devices and the inclusion of no-tool knobs for easy adjustment underline its user-friendly design. Whether it's a quick tweak to your setup or a significant adjustment, convenience is at your fingertips.
  • Versatility and Compatibility: Not just limited to Explore Scientific telescopes, this focuser's M82 x 1.25 pitch thread welcomes a variety of adapters and accessories. Whether you're using 2-inch or 3-inch visual or camera accessories, the twist-lock feature ensures everything stays secure.
  • Durable Construction: Crafted from black anodized aluminum and equipped with stainless-steel components, this focuser is built to last. It's not just a tool but a long-term investment in your astrophotography passion.
  • Back Cell Adapter: A back cell adapter with no-tool knobs attaches the focuser at four contact points to select Explore Scientific refractors with apertures ranging from 120mm to 140mm. The knobs on the adapter can be hand turned, eliminating the need for a hex key. This makes it easy to adjust the rotation of the focuser with minimal observing or imaging interruption. A Teflon ring on the focuser adds to the smooth rotation.


  • Explore Scientific white-tube telescopes with threaded back cells MUST BE shipped to Explore Scientific for installation of the back cell adapter. This will be arranged by customer service.
  • FPL53-165CF telescopes require the purchase of a new back cell adapter.
  • The Explore Scientific TED15208CF telescope does not require a back cell adapter. The 3-inch Self-Centering Focuser fits perfectly into the back cells.

Elevate Your Astrophotography Experience

With the Explore Scientific 3-Inch Self-Centering Focuser, every detail has been meticulously designed to enhance your viewing and imaging quality. Its superior build, combined with exceptional focusing capabilities, makes it a must-have for astrophotographers aiming for the stars. Upgrade your telescope with this focuser and step into a world where precision and quality converge to capture the universe in all its glory.

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Explore Scientific 3-inch Self-Centering Focuser | ES-FOC3 | 811803035683

Explore Scientific 3-inch Self-Centering Focuser

From $949.99 $1,139.99





Focal Length


Focal Ratio


Field of View




Barrel Size



3.32" (84.5mm) Draw Tube Travel

3" (76.2mm) Draw Tube Clear Interior Diameter


5.7 lb | 2.6 kg
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