While building a reflecting telescope (like a Newtonian or Dobsonian) is the traditional starting point for amateur telescope makers, making a refractor is often considered the peak of the craft.
To craft a long article, I have structured the content with clear, clickable headings. This will guide you through the myth, the accessible solution, and the practical path to building a world-class refractor.
Because light passes through a lens rather than reflecting off it, minor surface errors have a significantly reduced impact on the final wavefront. Furthermore, all four surfaces on a classic doublet are purely spherical. Spherical surfaces are naturally formed through the grinding process, making them far easier to polish and test than complex parabolas. Inside Chapter 12: The 7 Structural Prescriptions
Finding a specific troubleshooting tip for "scratches during fine grinding" or "pitch lap tempering" is significantly faster with a digital index search. Modern Adaptations for Today's Builders making a refractor telescope norman remer pdf 12 new
To counteract this, Remer’s book centers on the , an objective assembly that aligns two distinct glass elements to bring two primary wavelengths of light (usually red and blue) to the exact same focal point:
A series of internal rings with sharp edges must be placed inside the tube. These block stray reflections and ensure the background sky looks jet-black.
Look for authorized digital distributions through the American Astronomical Society (AAS) Sky Publishing catalog. While building a reflecting telescope (like a Newtonian
This article explores the core principles of Remer's refractor making process and highlights modern, 12-step refinements—or the "12 new" approaches—that can take your home-built refractor from good to exceptional. Why Build a Refractor?
For those seeking guidance on a 12-inch refractor, the book serves as a critical conceptual and theoretical foundation. While its direct prescriptions stop at 8 inches, the design and figuring principles it explains are fully applicable to larger apertures. To pursue a 12-inch project, you would need to pair the knowledge from Remer's book with advanced optical design software or collaborate with an experienced optician, as the book itself does not include a turn-key prescription for this size.
Every prescription details the exact radius of curvature for all four lens surfaces (R1, R2, R3, and R4). It also covers the target lens thicknesses and necessary air-space gaps. Because light passes through a lens rather than
Users have used the book to design custom achromats, such as 102mm or 130mm refractors , though some notes warn about the softness of specific glass types like SF1 when polishing.
You rub the two glass blanks against each other (or against a tool) with coarse grit to hollow out the desired radius of curvature.