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Explore Scientific 2x Focal Extender - 1.25"

Explore Scientific 2x Focal Extender - 1.25"

by Explore Scientific
SKU ES-FE02-125
CA$167.99 - CA$167.99
CA$167.99
CA$167.99 - CA$167.99
CA$167.99
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  • Doubles the magnification of any 1.25" eyepiece
  • Telecentric optical design ensures a true 2x power factor
  • Maintains the original eye relief of the eyepiece in use
  • Improves image quality compared to standard Barlow lenses
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  • Description
  • FAQ
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  • Explore Scientific 2x Focal Extender - 1.25"

    The Explore Scientific 2x Focal Extender doubles the power of any 1.25" eyepiece, effectively turning your existing accessory case into a collection with twice the magnification options. Its advanced telecentric optical design delivers a consistent and true 2x magnification factor, a critical advantage over traditional Barlow lenses, especially for astrophotography.

    Telecentric Design: A Stable 2x Magnification Factor

    Unlike a standard Barlow, which uses a negative lens group, the Explore Scientific Focal Extender employs a multi-element telecentric design. This system produces light rays that exit parallel to the optical axis, ensuring the 2x magnification remains constant regardless of the distance to the eyepiece or camera sensor. This provides predictable, sharp, and evenly illuminated views across the entire field, which is essential for consistent results in both visual observation and imaging.

    2x Power While Preserving Eyepiece Eye Relief

    One of the most significant ergonomic benefits of this focal extender is its ability to preserve the native eye relief of your eyepiece. Lower-power eyepieces typically have more generous eye relief, and by using the 2x extender, you can achieve high magnification while enjoying that same comfortable viewing distance. This makes high-power observing sessions more accessible and comfortable, especially for those who wear glasses.

    Focal Extender vs. Traditional Barlow: Why Telecentric Matters

    The choice between a focal extender and a Barlow lens comes down to optical stability and intended use. While both increase magnification, their methods differ significantly, leading to different outcomes.

    • Traditional Barlow Lens: A Barlow's magnification can vary depending on how far the eyepiece is spaced from the lens. This can be useful for fine-tuning image scale but introduces unpredictability. The diverging light cone can also induce vignetting and degrade edge-of-field sharpness, especially in fast telescopes.
    • Explore Scientific Focal Extender: The telecentric design provides a fixed, true 2x magnification that does not change with spacing. Its parallel light path is much gentler on complex eyepieces, preserving their designed optical corrections and maintaining image quality from the center to the edge of the field. This makes it the superior choice for imaging and for observers who demand consistency.

  • What is the main advantage of the Explore Scientific 2x Focal Extender over a standard 2x Barlow?

    The primary advantage is its telecentric optical design. This ensures a true, fixed 2x magnification regardless of eyepiece or camera spacing, providing more consistent and predictable results than a traditional Barlow lens, whose magnification can fluctuate with distance.

    How does the Explore Scientific 2x Focal Extender help observers who wear eyeglasses?

    This focal extender preserves the original eye relief of the eyepiece you pair it with. You can use a comfortable, long-eye-relief, low-power eyepiece to achieve high magnification, allowing you to keep your glasses on and still see the entire field of view.

    I have a 25mm eyepiece for my 8" f/10 SCT. What will the Explore Scientific 2x Focal Extender do?

    In a typical 8" f/10 SCT with a 2032mm focal length, your 25mm eyepiece provides about 81x magnification. Adding the Explore Scientific 2x Focal Extender will double that to approximately 162x, giving you a much closer view of planetary detail on objects like Jupiter or Saturn, all while you continue to use your comfortable 25mm eyepiece.

    Can I use the Explore Scientific 2x Focal Extender to image Jupiter with my planetary camera?

    Absolutely. The telecentric design is ideal for planetary imaging. It increases your telescope's effective focal length by a precise 2x factor, enlarging the planet on your camera sensor without introducing the optical aberrations that can occur with standard Barlow lenses in an imaging train.

    Will the Explore Scientific 2x Focal Extender work with my specialty eyepieces?

    Yes, the parallel light path from the telecentric design is much more forgiving on complex, wide-field eyepieces than the steep light cone from a Barlow. It helps maintain the high-quality performance your premium eyepieces were designed to deliver, even at double the power.

    Does adding the Explore Scientific 2x Focal Extender reduce image brightness?

    Any time you increase magnification, the image will become dimmer because the same amount of light is spread over a larger area. While the multi-coated optics in the focal extender are highly efficient, the dimming you perceive is a direct and unavoidable consequence of the 2x increase in magnification, not a loss of light through the device itself.

  • GTIN 8122570104178
  • Explore Scientific Warranty