Refractor Light Grasp Calculator

Calculate Light Gathering Power for Refractor Telescopes

Telescope Specifications

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Calculation Formula
Light Grasp = π × (Aperture ÷ 2)²

Where:

  • π (Pi) ≈ 3.14159
  • Aperture = Diameter of the objective lens
  • Refractor telescopes have no central obstruction, providing 100% of theoretical light gathering
About Refractor Telescopes: Refractors use lenses to gather and focus light, providing excellent contrast and sharp images. Unlike reflectors and catadioptric telescopes, refractors have no central obstruction, meaning they deliver 100% of their theoretical light gathering capability. This makes them ideal for lunar, planetary, and double star observing.