Explore Scientific 3" Carbon Fiber Dielectric Diagonal

  • Sale
  • Regular price $409.99
  • ITEM #



  • Diagonal Type: Star Diagonal
  • Compatible with 3" Eyepieces
  • 99% reflectivity internal mirror

Explore Scientific 3" Carbon Fiber Dielectric Diagonal

This 3" Carbon Fiber Dielectric Diagonal was made to support the use of 3" eyepieces such as the Explore Scientific 30mm 100 degree Argon Purged Waterproof Eyepiece in refractors outfitted with 3" focusers. Mirror features 99% reflectivity and dielectric coatings.

OPT Product Number:ES-DD03-01CF

Additional Information

ManufacturerExplore Scientific
  • Explore Scientific 3" Carbon Fiber Dielectric Diagonal
  • 3" - 2" Eyepiece Adapter

Questions & Answers

Ask a Question
  • Is this an actual product? I went to the ES site to get some dimensional information, but this diagonal doesn't appear there and when I contacted them they said that they don't make a 3" diagonal, so I'm confused.

    I just spoke to someone in Sales at Explore Scientific and they said that they still make this 3" diagonal. It's currently the only way to use their 3" 30mm 100 degree eyepiece on their larger refractors with 3" focusers.

  • Hello. Can this be used with a C11 Edge HD?

    Technically, yes, although you will need to have a machinist make a custom 3.29"-16 TPI to 3" receiver to attach it to the scope, and with the C11 having an inner baffle diameter not much more than 51mm wide, it will not illuminate a 3" eyepiece fully.

  • what is the total optical path length through the diagonal?

    The manufacturer does not state this, but by measuring a photograph and comparing it to the manufacturer's statements about the physical size of the housing, the optical path length appears to be approximately 5" (127mm) in length, just a bit longer than

Make easy monthly payments over 3, 6, or 12 months

Rates from 10–30% APR.

Quick and easy

Enter a few pieces of information for a real-time decision. Checking your eligibility won't affect your credit score.

No hidden fees

Know up front exactly what you'll owe, with no hidden costs and no surprises.

Just select Affirm at checkout.