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DayStar 130mm ERF with 190mm Inside Diameter Cap

by DayStar
SKU E-190N130
Original price $995.00 - Original price $995.00
Original price
$995.00 - $995.00
Current price $995.00
In stock

Ships To: United States & Canada 🇺🇸 🇨🇦

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DayStar 130mm Energy Rejection Filter with 190mm Inside Diameter Cap - For Refractor - E-190N130

Presenting the DayStar 130mm Energy Rejection Filter with a 190mm Inside Diameter Cap, specially designed for refractor telescopes.

These state-of-the-art filters are meticulously crafted to significantly diminish the thermal stress on your filter setup.

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

You can choose from variants featuring Red or Yellow glass, or opt for those crafted with cutting-edge dielectric IR and UV materials.

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

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

For peak performance, DayStar recommends utilizing filter assemblies at f/30 or slower.

Achieving this setup is effortlessly done with the appropriate ERF and/or Barlow lens. In cases of higher resolution or larger aperture configurations, incorporating a Barlow is advised for an enriched 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 you plan to use with this ERF and carefully measure the outer diameter of the telescope's dew shield at the front using a ruler. This accurate measurement is crucial, as ERFs are crafted specifically for each telescope to guarantee a seamless fit.
  • If this measurement is not provided, it may lead to a temporary delay in processing your order until the required information is provided. Your satisfaction and optimal performance is our priority.


Features & Highlights:

  • 130mm Energy Rejection Filter (ERF) Glass: A finely engineered optical element created with precision to effectively mitigate thermal effects on your filter assembly. Through adept absorption or reflection of UV and IR light, it exclusively permits the desired visual spectrum to pass through. This deliberate filtration process ensures a consistently unobstructed viewing experience, minimizing any possible disturbances arising from thermal influences.

  • Efficient Thermal Management: The DayStar Energy Rejection Filter is meticulously engineered to significantly reduce the heat load on your filter assembly. Through adept absorption or reflection of UV and/or IR light, it exclusively permits light within the desired visual spectrum to pass through. This guarantees a clear and consistent viewing experience, minimizing thermal interference.
  • Tailored Filtration Options: Designed to cater to specific observational requirements, this filter offers a diverse range of material choices. Whether you opt for Red or Yellow glass, or choose dielectric coatings, each option excels in effectively blocking undesirable UV and IR wavelengths. This versatility aligns seamlessly with your precise goals.
  • Optical Precision and Clarity: While proficiently screening out UV and IR, this filter truly shines in its ability to transmit light within the desired visual spectrum. This unwavering commitment to optical clarity ensures that your observations remain characterized by precision, free from distortions, and unparalleled in their clarity.
  • 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 advises operating filter assemblies at f/30 or slower settings for peak performance. Achieving this configuration is straightforward with the inclusion of the appropriate ERF and/or barlow, ensuring perfect alignment within your telescope's optical system.
  • Comprehensive Compatibility and Expert Guidance: DayStar provides an extensive list of compatible reflectors and refractors to simplify your selection process. If you have a specific telescope model in mind, their experienced team is readily available to guide you towards the perfect filter for your equipment.
  • Critical Measurement Precision Requirement: To expedite customization, 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.
  • Robust and Protective Build: The ERF is securely housed in a robust cell with a 190mm ID cap. This additional layer of protection ensures the filter's longevity and sustained high performance by safeguarding it when not in use.


                  What's Included:

                  ✓ DayStar 130mm ERF with 190mm ID Cap

                  ✓ 5 Year Warranty



                  SKU E-190N130
                  Block Ultraviolet Yes
                  Block Infrared Yes


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