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DayStar 130mm ERF with 150mm Inside Diameter Cap

by DayStar
SKU E-150N130
Special Order
Original price $995.00 - Original price $995.00
Original price
$995.00 - $995.00
Current price $995.00

Lead-time: 2-4 weeks

Ships To: United States & Canada 🇺🇸 🇨🇦

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We offer free U.S. shipping to the lower 48 States - on most orders over $150 USD. Some limitations may apply.

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We offer a 30 Day Return Policy on most of the products that we carry.

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The vast majority of products that we sell, with a few exceptions, are covered under Warranty.

To view the Warranty details for each brand that we sell, including products that do not qualify for Warranty, please visit here.

DayStar 130mm Energy Rejection Filter with 150mm Inside Diameter Cap - For Refractor - E-150N130

Presenting the DayStar 130mm Energy Rejection Filter, designed specifically for refractor telescopes, featuring an inside diameter cap of 150mm.

These advanced filters are meticulously engineered to dramatically reduce the heat strain on your filter assembly.

They achieve this by efficiently absorbing or reflecting UV and/or infrared light, ensuring the seamless transmission of light within the desired visual spectrum.

You can choose from various options, including filters crafted from either Red or Yellow glass, or those employing dielectric IR and UV materials.

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

One standout feature of the ERF is its dual function as an aperture mask. This not only ensures a direct angle of incidence for incoming light but also enhances filtering efficiency.

For the best performance, DayStar recommends using filter assemblies at f/30 or slower.

Achieving this configuration is a breeze with the right ERF and/or Barlow. In cases where higher resolution or larger aperture configurations are desired, the addition of a Barlow is recommended to elevate your 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:

  • Please specify the telescope intended for use with this ERF and take careful measurements of the outer diameter of the telescope's dew shield at the front, using a ruler. This precise measurement is crucial, as ERFs are custom made on a case-by-case basis to guarantee a seamless fit.
  • If this measurement is not provided, it may lead to a temporary pause in processing your order until the required information is obtained. Your satisfaction and optimal performance is our priority.

Features & Highlights:

  • 130mm Energy Rejection Filter (ERF) Glass: An intricately engineered optical element created to effectively mitigate thermal effects on your filter assembly. Through its adept absorption or reflection of UV and IR light, it selectively permits only the desired visual spectrum, ensuring a consistently clear viewing experience. This meticulous filtration process serves to minimize any potential disturbances arising from thermal influences.

  • Excellence in Thermal Control: DayStar's Energy Rejection Filters are meticulously engineered to excel in managing the thermal dynamics of your filter assembly. Their adept ability to either absorb or reflect UV and/or IR light ensures that only light within the desired visual spectrum is allowed to pass through. This safeguarding mechanism is instrumental in sustaining a consistent, unwavering performance by shielding the telescope's vital optical components.
  • A Plenitude of Material Choices: These filters offer a rich array of material options to cater to your precise observational needs. Whether you opt for Red or Yellow glass or choose dielectric coatings, each alternative excels in effectively blocking undesired UV and IR wavelengths. This versatility aligns seamlessly with your unique goals.
  • Brilliance in the Visual Spectrum: While proficiently filtering out UV and IR, these filters truly shine in their ability to transmit light within the desired visual spectrum. This unwavering commitment to optical clarity ensures that your observations and images remain characterized by precision, free from distortions, and unparalleled in their clarity.
  • A Dual Role as an Aperture Mask: The Energy Rejection Filter (ERF) serves as more than just a filter; it takes on a dual function as an aperture mask. By guaranteeing that incoming light reaches the telescope's optics at the perfect, direct angle, it significantly amplifies the quality and precision of your observations.
  • Optimal Operational Settings: DayStar filter assemblies reach their zenith in performance when configured at f/30 and slower settings. This ideal setup is effortlessly achieved with the inclusion of the appropriate ERF and Barlow, ensuring impeccable alignment within your telescope's optical system.
  • Tailored Compatibility: Streamline your filter selection process with DayStar's extensive list of compatible reflectors and refractors. Should you have a specific telescope model in mind, the experienced DayStar team is readily available to guide you towards the perfect filter for your equipment.
  • Precision in the Art of Custom Machining: ERFs undergo a meticulous process of custom machining, underscoring an unwavering commitment to precision and detail in the manufacturing process. This ensures that the filter is seamlessly tailored to meet your telescope's unique requirements, guaranteeing a precise and accurate fit.
  • Critical Measurement Precision: To expedite the customization process, DayStar kindly requests that you provide an accurate measurement of the outermost (largest) diameter of your telescope's dew shield at its foremost end. This level of precision is paramount in securing a flawless fit and optimizing the performance of your ERF. Be assured, your satisfaction and the quality of your viewing experience remain DayStar's foremost priorities.
  • Durable and Protective Construction: The ERF is securely housed in a robust cell with a 150mm ID cap. This cap provides an extra layer of protection, safeguarding the filter when not in use, ensuring longevity and continued high performance.


        What's Included:

        ✓ DayStar 130mm ERF with 150mm ID Cap

        ✓ 5 Year Warranty



        SKU E-150N130
        Block Ultraviolet Yes
        Block Infrared Yes


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