Explore Scientific Adapter For 3" Field Flattener .7x Reducer To Attach To 2.5" Hex Focuser

Explore Scientific Adapter for 3" Field Flattener / 0.7x Reducer to Attach to 2.5" Hex Focuser

If you're using the Explore Scientific 2.5" Hex Focuser and looking to expand your astrophotography capabilities, this dedicated adapter lets you seamlessly integrate the Explore Scientific 3" Field Flattener / 0.7x Reducer with your imaging setup. It’s a simple yet critical upgrade for achieving pinpoint stars across a wider field and reducing your effective focal length for faster imaging.

Precision Fit and Optical Compatibility

Designed specifically by Explore Scientific, this adapter ensures a secure mechanical connection between your 2.5" Hexagonal focuser and the larger 3" flattener/reducer assembly. This is not a generic part — it's engineered for precise alignment and rigidity to maintain the critical backfocus and optical path required for optimal performance.

The adapter threads directly onto the rear of the 2.5" Hex Focuser, replacing the standard 2" or 2.5" visual back. On the flattener/reducer side, it accepts the 3" component with an exact fit, ensuring no tilt, flex, or misalignment that could degrade your images.

Designed for Astrophotography

This adapter exists purely for imagers. When combined with the 3" Field Flattener / 0.7x Reducer, you'll get a flatter, wider field with reduced vignetting, making it perfect for full-frame and APS-C sensors. The reducer drops your focal ratio by 30%, allowing for shorter exposures and improved performance with faint targets — ideal for nebulae, wide star fields, and larger galaxies.

Whether you're using an Explore Scientific ED102, ED127, or other compatible refractor with a 2.5" Hex Focuser, this adapter makes it possible to expand your system with the more robust 3" optics designed for larger-format imaging.

Built to Last

Machined from high-quality aluminum with a black anodized finish, this adapter is both durable and lightweight. The internal surfaces are matte black to reduce stray reflections and maintain image contrast. Threading is clean and precise, providing a solid mechanical lock with minimal play.

No Tools, No Hassle

Installation is straightforward. Simply unthread the existing rear accessory collar from your 2.5" Hex Focuser, thread on the adapter, and then connect your 3" reducer/flattener. Once everything is locked into place, you're ready to attach your imaging train and begin capturing sharper, wider-field images.

Key Features:

• Allows attachment of Explore Scientific 3" Field Flattener / 0.7x Reducer to 2.5" Hex Focuser
• Custom-threaded for perfect fit and alignment
• Maintains critical backfocus and optical integrity
• Ideal for full-frame and APS-C sensor cameras
• Machined aluminum construction with anti-reflective interior finish
• Simple installation — no modifications or tools required

In Summary

If you're serious about wide-field astrophotography and want to take full advantage of your Explore Scientific optics, this adapter is an essential piece of the puzzle. It bridges the gap between your high-precision focuser and the power of the 3" reducer/flattener system, unlocking better image quality across the board.

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