• Explore Scientific 3 inch self centering focuser with back cell adapter ES-FOC3-BC100127 designed for large refractor telescopes providing beginner astrophotographers with smooth precise wobble free and self centering focusing performance for sharp detailed and perfectly centered planetary lunar and deep sky imaging — Telescope Wolves
  • Explore Scientific 3 inch self centering focuser with back cell adapter ES-FOC3-BC100127 complete parts layout showing focuser body back cell adapter hardware and all included components for beginner astrophotographers planning a large aperture refractor telescope focuser upgrade — Telescope Wolves
  • Explore Scientific 3 inch self centering focuser with back cell adapter ES-FOC3-BC100127 shown attaching to a large aperture refractor telescope demonstrating the precise secure and straightforward back cell installation process for beginner astrophotographers upgrading their focuser for sharper more precise deep sky imaging — Telescope Wolves
  • Alternate angle installation view of Explore Scientific 3 inch self centering focuser with back cell adapter ES-FOC3-BC100127 revealing precise back cell threading engagement secure mounting connection and overall focuser to telescope fit for beginner astrophotographers upgrading their large aperture refractor telescope focuser — Telescope Wolves
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Explore Scientific

Explore Scientific 3" Self-Centering Focuser with Back-Cell Adapter for Large Refractors | Telescope Wolves

Explore Scientific 3" Self-Centering Focuser with Back-Cell Adapter for Large Refractors | Telescope Wolves

$999.99
$999.99
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Shipping calculated at checkout.

Precision focus control for large-aperture refractors and astrophotography. The Explore Scientific 3-inch Self-Centering Focuser (ES-FOC3-BC100127) provides smooth, slip-free focus travel with a self-centering drawtube that eliminates image shift — critical for high-resolution planetary imaging and long-exposure deep-sky photography where any focus wobble ruins a frame. The included back-cell adapter connects it to compatible large refractor optical tubes. A significant performance upgrade over standard rack-and-pinion focusers. Ships free to the US.

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Frequently Asked Questions

With a beginner telescope you can see a surprising amount — the craters and mountains on the Moon, the rings of Saturn, the moons of Jupiter, and star clusters like the Pleiades. As you get more comfortable, you can also spot nebulae and distant galaxies. Not sure which beginner telescope is right for you? Check out our Telescope Buying Guide.
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Yes! If you find a lower price at another authorized online retailer within 6 months of your purchase, we'll refund the difference. Learn more on our Price Match Guarantee page.
All telescopes on Telescope Wolves are hand-picked with beginners in mind. If you're unsure which telescope is right for you, check out our Telescope Buying Guide.
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