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DayStar 100mm ERF with 130mm Inside Diameter Cap

by DayStar
SKU E-130N100
Original price $695.00 - Original price $695.00
Original price
$695.00 - $695.00
Current price $695.00
In stock

Ships To: United States & Canada 🇺🇸 🇨🇦

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DayStar 100mm Energy Rejection Filter with 130mm Inside Diameter Cap - For Refractor - E-130N100

Meticulously crafted DayStar 100mm Energy Rejection Filter featuring a 130mm Inside Diameter Cap, custom-made for refractor telescopes.

These cutting-edge filters are meticulously designed to greatly diminish the thermal stress on your filter setup.

This is achieved through the effective absorption or reflection of UV and/or infrared light, ensuring seamless transmission within the desired visual spectrum.

You have the option of choosing from Red or Yellow glass variants, or employing dielectric materials for IR and UV filtration.

These filters guarantee precise filtration while allowing the passage of the desired wavelengths.

Noteworthy is the ERF's dual functionality as an aperture mask, guaranteeing a direct angle of incidence for incoming light, thereby heightening filtering efficiency.

For peak performance, DayStar advises operating filter setups at f/30 or slower. This setup can be effortlessly achieved with the appropriate ERF and/or Barlow lens.

In cases of higher resolution or larger aperture configurations, incorporating a Barlow lens is recommended for an enhanced viewing experience.

Important Instructions:

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

  • Specify the telescope intended for use with this ERF and meticulously measure the outer diameter of the telescope's dew shield at the front using a ruler. This precise measurement is paramount, as ERFs are custom made on an individual basis to ensure a perfect fit.
  • Failure to provide this measurement may result in a temporary hold on your order until the necessary information is retrieved. Your satisfaction and optimal performance is our priority.

Features & Highlights:

  • 100mm Energy Rejection Filter (ERF) Glass: Is an intricately crafted optical component carefully designed to efficiently address thermal impacts on your filter assembly. Through skillful absorption or reflection of UV and IR light, it exclusively allows the desired visual spectrum to pass through. This thoughtful filtration process ensures a consistently clear viewing experience, minimizing potential disruptions caused by thermal effects.
  • Heat Load Management: Engineered to safeguard your filter assembly, DayStar's Energy Rejection Filters expertly absorb or reflect UV and/or IR light while allowing desired visual spectrum light to pass through. This critical feature shields your telescope's optical components from excessive heat, assuring consistent and dependable performance.
  • Diverse Material Options: Available in an array of materials, including Red or Yellow glass and specialized dielectric coatings, these filters are tailored to address specific observational objectives. This versatility empowers you to select the ideal material for your unique needs.
  • Unparalleled Visual Clarity: While effectively screening UV and IR wavelengths, these filters excel in transmitting light within the desired visual spectrum. This meticulous balance ensures that your observations and captured images are devoid of distortions, delivering precision and clarity.
  • Multi-Functional ERF: The Energy Rejection Filter (ERF) goes beyond its primary function, also acting as an aperture mask. By ensuring that incoming light strikes the telescope's optics at an optimal, direct angle, this feature significantly enhances observation quality.
  • Optimized Operating Parameters: DayStar advises configuring filter assemblies at f/30 or slower settings for peak performance. This alignment is effortlessly achieved with the appropriate ERF and Barlow, ensuring your telescope's optical system is finely tuned.
  • Tailored Compatibility: Simplifying your selection process, DayStar offers an extensive list of compatible reflectors and refractors. For personalized recommendations based on your specific telescope model, their knowledgeable team is readily available to assist you.
  • Precision Manufacturing: Every ERF undergoes custom machining, a testament to the meticulous attention to detail in the manufacturing process. This ensures that each filter is precisely tailored to meet your telescope's unique requirements, guaranteeing a seamless and accurate fit.
  • Critical Measurement Precision: To expedite the customization process, DayStar emphasizes the importance of providing an accurate measurement of your telescope's dew shield's outer (largest) diameter at the foremost end. This level of precision is essential to ensure the flawless fit and performance of your ERF, ensuring an optimal viewing experience
  • Durable and Protective Construction: The ERF features a robust cell with a 130mm ID cap, providing an extra layer of protection. This ensures the filter's longevity and continued high performance, safeguarding it when not in use.


    What's Included:

    ✓ DayStar 100mm ERF with 130mm ID Cap

     ✓ 5 Year Warranty



    SKU E-130N100
    Block Ultraviolet Yes
    Block Infrared Yes


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