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DayStar 150mm ERF with 200mm Inside Diameter Cap

by DayStar
SKU E-200N150
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

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DayStar 150mm Energy Rejection Filter with 200mm Inside Diameter Cap - For Refractor - E-200N150

Presenting the DayStar 150mm Energy Rejection Filter, featuring a 200mm Inside Diameter Cap, specially designed for refractor telescopes.

These advanced filters are meticulously engineered to substantially alleviate the thermal stress on your filter assembly.

This is achieved by efficiently either absorbing or reflecting ultraviolet (UV) and/or infrared (IR) light, allowing the seamless transmission of light within the desired visual spectrum.

You can choose from a variety of options, such as Red or Yellow glass variants or opt for filters made with dielectric IR and UV materials.

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

Notably, the ERF also serves as an aperture mask, ensuring a direct angle of incidence for incoming light, thereby enhancing filtering efficiency.

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

Achieving this configuration is easily accomplished with the appropriate ERF and/or Barlow.

In cases of higher resolution or larger aperture setups, the inclusion of a Barlow is recommended for an enhanced and superior 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 indicate the telescope model for which this ERF is intended and carefully measure the outer diameter of the telescope's dew shield at the front using a ruler. This accurate measurement is crucial, as our ERFs are tailored to each telescope to guarantee a precise fit.
  • If this measurement is not provided, it may lead to a temporary delay in processing your order until the required information is received. Your satisfaction and optimal performance is our priority.


Features & Highlights:

  • 150mm Energy Rejection Filter (ERF) Glass: A carefully constructed optical element engineered to effectively mitigate thermal effects on your filter assembly. It accomplishes this by adeptly absorbing or reflecting UV and IR light, ensuring that only the intended visual spectrum is transmitted. This precise filtration process ensures a reliably unobstructed viewing experience, reducing any potential disturbances caused by thermal influences.

  • Efficient Thermal Management: The DayStar Energy Rejection Filter is meticulously engineered to significantly reduce thermal impact on your filter assembly. Through adept absorption or reflection of UV and/or IR light, it selectively allows only light within the desired visual spectrum to pass through. This ensures a consistently clear viewing experience, minimizing any disruptions caused by thermal effects.
  • Tailored Filtration Options: Designed to meet specific observational requirements, this filter offers a versatile range of material choices. Whether you opt for Red or Yellow glass, or choose dielectric coatings, each option excels in effectively blocking unwanted UV and IR wavelengths. This adaptability seamlessly aligns with your precise objectives.
  • Uncompromising Optical Precision and Clarity: While efficiently filtering out UV and IR, this filter excels in transmitting 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 unparalleled in their clarity.
  • Enhanced Aperture Mask Functionality: Beyond its primary filtering function, the Energy Rejection Filter (ERF) also serves as an aperture mask. This guarantees that incoming light meets the telescope's optics at a direct and optimal angle, significantly enhancing the quality and precision of your observations.
  • Optimized Performance Setup: 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 necessary, a Barlow. This guarantees flawless alignment within your telescope's optical system.
  • Extensive Compatibility and Expert Guidance: DayStar offers an extensive list of compatible reflectors and refractors, simplifying your selection process. If you have a specific telescope model in mind, their experienced team is readily available to steer you towards the perfect filter for your equipment.
  • Critical Precision in Measurement Requirement: To streamline the customization process, it is vital 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.
  • Robust and Protective Construction: The ERF is securely housed in a sturdy cell with a 200mm 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 200mm ID Cap

                      ✓ 5 Year Warranty



                      SKU E-200N150
                      Block Ultraviolet Yes
                      Block Infrared Yes


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