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DayStar 125mm Off-Axis ERF with 460mm Inside Diameter Cap

by DayStar
SKU E-460F125
Original price $1,195.00 - Original price $1,195.00
Original price
$1,195.00 - $1,195.00
Current price $1,195.00
In stock

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DayStar Off-Axis 125mm Energy Rejection Filter with 460mm Inside Diameter Cap - for 16-inch SCT - E-460F125

The DayStar 125mm Off-Axis Energy Rejection Filter, equipped with a 460mm Inside Diameter Cap, is specifically designed for use with 16-inch Schmidt-Cassegrain Telescopes (SCTs).

These Energy Rejection Filters play a crucial role in maintaining optimal operating conditions for your filter system.

They achieve this by either absorbing or reflecting harmful UV and/or I light, while still allowing light in the visual spectrum to pass through.

These filters can be made of materials like Red or Yellow glass, or dielectric substances that effectively filter out IR and UV wavelengths, while permitting desired visible light.

Moreover, the ERF serves an additional purpose as an aperture mask, ensuring that incoming light hits the filter at a direct angle.

It's important to note that DayStar filter assemblies work most effectively at focal ratios of f/30 and slower.

Fortunately, achieving this configuration is a straightforward process with the right ERF and/or Barlow lens.

This combination ensures that your telescope operates optimally, providing clear and high-quality observations of celestial objects.

 Important Instructions:

To facilitate a seamless integration, after your order is placed, please reach out to us via email with the following details:

  • Please specify the telescope designated for ERF use and meticulously measure the outer diameter of the front dew shield using a ruler. This precise measurement is vital, as ERFs are custom made for a perfect fit.
  • If this measurement is not provided, there may be a temporary delay in processing your order until we receive the necessary information. Your satisfaction and optimal performance is our priority.

      Features & Highlights:

      • 125mm ERF Glass: With precision craftsmanship, the 125mm ERF aperture is tailored for optimal solar observation. It strikes a delicate balance between light-gathering capacity and resolution, offering clear, detailed views of solar phenomena.
      • 460mm Inside Diameter Cap: Included in the package is a 460mm inside diameter cap, ensuring a secure and snug fit with compatible telescopes. This cap plays a vital role in minimizing stray light, enabling precise and unobstructed solar observations.
      • SCT Compatibility: Engineered specifically for 16-inch SCT (Schmidt-Cassegrain) telescopes, the ERF seamlessly integrates with your existing optical setup. This ensures a seamless, hassle-free, and effective solar observation experience.
      • Advanced Energy Rejection: The ERF is meticulously designed to significantly diminish the heat load on your filter assembly. This is achieved through efficient absorption or reflection of UV and/or Infrared light, allowing the transmission of light within the desired visual spectrum.
      • Multi-Coated Optics: All optical surfaces are expertly multi-coated to enhance light transmission and minimize internal reflections. This results in vivid, high-contrast solar images with exceptional clarity and detail.
      • Off-Axis Design: The off-axis design provides an unobstructed view of the solar disk, maximizing the amount of light collected by the telescope. This design feature ensures precise observation of the sun's features.
      • Dual Functionality as an Aperture Mask: The ERF serves a dual purpose as an aperture mask, ensuring a direct angle of incidence for incoming light. This unique feature enhances filtering efficiency, ensuring that only the desired wavelengths are transmitted.
      • Robust Construction: Constructed from high-quality materials, the ERF guarantees durability and longevity. It is designed to withstand the rigors of outdoor use and maintain peak performance over time.
      • Recommendations for Optimal Performance: For the best results, DayStar recommends operating filter assemblies at f/30 or slower. This configuration is easily achieved with the appropriate ERF and/or Barlow. In cases of higher resolution or larger aperture configurations, the addition of a Barlow is recommended for an enhanced viewing experience.


                      What's Included:

                      ✓ DayStar 125mm Off-Axis ERF for 16-inch SCT

                       ✓ 5 Year Warranty



                      SKU E-460F125
                      Block Ultraviolet Yes
                      Block Infrared Yes

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