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DayStar 80mm ERF with 110mm Inside Diameter Cap

by DayStar
SKU E-110N80
Special Order
Original price $550.00 - Original price $550.00
Original price
$550.00 - $550.00
Current price $550.00


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 80mm Energy Rejection Filter with 110mm Inside Diameter Cap - For Refractor - E-110N80

Introducing the DayStar Energy Rejection-Refractor 80mm ERF Glass, Cell, and 110mm ID Cap, meticulously crafted for refractor telescopes.

These specialized filters are engineered to alleviate heat strain on your filter assembly by either absorbing or reflecting UV and/or IR light, while ensuring the transmission of light within the desired visual spectrum.

They come in variants of Red or Yellow glass, or dielectric IR and UV, tailored to meet distinct observational needs.

The ERF, a vital component, also functions as an aperture mask, ensuring a direct angle of incidence for incoming light entering the filter.

It is crucial to note that DayStar filter assemblies perform optimally at f/30 and slower configurations.

Achieving an f/30 setup can be effortlessly attained with the appropriate ERF and/or Barlow.

For precise compatibility, we encourage you to explore our comprehensive list of compatible reflectors and refractors.

If you have a specific model in mind, our team is readily available to assist you in making the ideal selection.

 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 intended for use with this ERF and carefully measure the outer diameter of the telescope's dew shield at the front using a ruler. This precise measurement is crucial, as ERFs are individually custom made to guarantee a flawless fit.
  • If this measurement is not provided, it may lead to a temporary hold on your order until the necessary information is obtained. Your satisfaction and optimal performance is our priority.

Features & Highlights:

  • Heat Load Reduction: The DayStar Energy Rejection Filters are designed to reduce the heat load on your filter assembly by efficiently absorbing or reflecting UV and/or IR light while permitting light within the desired visual spectrum to pass through. This feature prevents excess heat from reaching the telescope's optical components, ensuring consistent and reliable performance.
  • Variety of Filter Materials: These filters come in different material options, including Red or Yellow glass and dielectric coatings designed to block unwanted UV and IR wavelengths. The choice of material can be tailored to specific observational needs and goals.
  • Optical Clarity in the Visual Spectrum: While blocking UV and IR, the filters excel in transmitting light within the desired visual spectrum. This ensures that observations and images captured with these filters are free from distortions and optimized for clarity and precision.
  • Aperture Mask Functionality: The ERF (Energy Rejection Filter) also serves as an aperture mask, ensuring that incoming light is incident on the telescope's optics at a direct and optimal angle. This feature contributes to the filter's ability to enhance the quality of observations.
  • Optimal Operating Conditions: DayStar filter assemblies perform at their best when configured at f/30 and slower settings. Achieving this configuration is made convenient with the appropriate ERF and Barlow, ensuring that your telescope's optical system is perfectly aligned.
  • Custom Compatibility: DayStar provides a comprehensive list of compatible reflectors and refractors to simplify your selection process. If you have a specific telescope model in mind, their knowledgeable team is available to guide you toward the ideal filter for your equipment.
  • Precision Machining: ERFs are custom machined on a one-off basis, highlighting the attention to detail and precision in their manufacturing process. The filter is tailored to your specific telescope's requirements, ensuring a seamless and accurate fit.
  • Measurement Accuracy Requirement: To expedite the customization process, DayStar requests that you provide an accurate measurement of the outer (largest) diameter of your telescope's dew shield at the foremost end. The precision of this measurement is essential to ensure the perfect fit and performance of your ERF.

What's Included:

✓ DayStar 80mm ERF Glass

✓ DayStar ERF Cell

✓ 110mm ID Cap

 ✓ 5 Year Warranty


SKU E-110N80
Block Ultraviolet Yes
Block Infrared Yes

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