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DayStar 150mm ERF with 190mm Inside Diameter Cap

by DayStar
SKU E-190N150
Original price $1,645.00 - Original price $1,645.00
Original price
$1,645.00 - $1,645.00
Current price $1,645.00
In stock

Ships To: United States & Canada 🇺🇸 🇨🇦

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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 150mm Energy Rejection Filter with 190mm Inside Diameter Cap - For Refractor - E-190N150

Discover the DayStar 150mm Energy Rejection Filter with a 190mm Inside Diameter Cap, specifically designed for refractor telescopes.

These advanced filters have been meticulously engineered to substantially alleviate the heat stress on your filter setup.

This is achieved by proficiently absorbing or reflecting UV and/or Infrared light, enabling the seamless transmission of light within the desired visual spectrum.

Available in multiple variations, including Red or Yellow glass, or utilizing cutting-edge dielectric IR and UV materials, these filters offer precise filtration while allowing the passage of desired wavelengths.

A remarkable feature of the ERF is its dual functionality as an aperture mask, guaranteeing a direct angle of incidence for incoming light and thereby augmenting filtering efficiency.

For the best results, DayStar recommends operating filter assemblies at an f/30 or slower configuration.

Achieving this setup is effortlessly accomplished with the appropriate ERF and/or Barlow lens.

In scenarios requiring higher resolution or larger aperture configurations, the addition of a Barlow lens is advised to enhance your overall 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 ensure you indicate the telescope you plan to use with this ERF and take accurate measurements of the outer diameter of the telescope's dew shield at the front using a ruler. This precise information is crucial, as our ERFs are custom-made to fit each telescope perfectly.
  • If this measurement is not provided, it may lead to a temporary delay in processing your order until we receive the necessary details. Your satisfaction and optimal performance is our priority.


Features & Highlights:

  • 150mm Energy Rejection Filter (ERF) Glass: Carefully engineered optical element with the specific purpose of effectively mitigating thermal effects on your filter assembly. Through adeptly absorbing or reflecting UV and IR light, it selectively permits only the desired visual spectrum to pass through. This deliberate filtration process ensures a consistently sharp and uninterrupted viewing experience, reducing any potential disturbances caused by thermal influences.

  • Efficient Thermal Control: The DayStar Energy Rejection Filter is meticulously crafted to notably diminish the thermal impact on your filter assembly. By skillfully absorbing or reflecting UV and/or IR light, it exclusively allows light within the desired visual spectrum to pass through. This guarantees a consistently clear viewing experience, minimizing any thermal disruptions.
  • Customized Filtration Possibilities: Tailored to meet specific observational demands, this filter provides a versatile range of material options. Whether you choose Red or Yellow glass, or opt for dielectric coatings, each choice excels in proficiently obstructing undesirable UV and IR wavelengths. This adaptability seamlessly aligns with your precise objectives.
  • Unwavering Optical Precision and Clarity: While effectively sieving out UV and IR, this filter truly stands out in its ability to transmit light within the desired visual spectrum. This steadfast commitment to optical clarity ensures that your observations maintain a hallmark of precision, free from distortions, and unrivaled in their clarity.
  • Aperture Mask Functionality Amplified: Beyond its primary filtering role, the Energy Rejection Filter (ERF) also serves as an aperture mask. This ensures that incoming light meets the telescope's optics at a direct and optimal angle, significantly elevating the quality and precision of your observations.
  • Optimized Performance Configuration: DayStar recommends configuring filter assemblies at f/30 or slower settings for peak performance. Achieving this setup is a straightforward process with the inclusion of the appropriate ERF and, if required, a Barlow. This ensures flawless alignment within your telescope's optical system.
  • Extensive Compatibility and Expert Advisory: DayStar provides an extensive list of compatible reflectors and refractors, simplifying your selection process. Should you have a specific telescope model in mind, their seasoned team is readily available to guide you towards the perfect filter for your equipment.
  • Vital Precision in Measurement Requirement: To streamline the customization process, it is crucial to specify the telescope model and provide an accurate measurement (using a ruler) of the outer (largest) diameter of your telescope's dew shield at the front. This precision is paramount, as each ERF is individually machined to ensure seamless integration with your telescope.
  • Sturdy and Protective Construction: The ERF is securely housed in a robust cell with a 190mm ID cap. This additional layer of protection guarantees the filter's longevity and sustained high performance by safeguarding it when not in use.


                    What's Included:

                    ✓ DayStar 150mm ERF with 190 ID Cap

                    ✓ 5 Year Warranty



                    SKU E-190N150
                    Block Ultraviolet Yes
                    Block Infrared Yes


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