It sounds like you are looking for a specific document: "Making a Refractor Telescope" by Norman Remer, likely a PDF, and you’ve added the phrases “12 new” and “interesting essay.”

Summary

If you are looking to build a refractor, this is the correct book to have. However, you will likely need to purchase a physical copy, as a digital PDF version is not officially distributed. If you were looking for his specific math on mirror figuring, you likely want to search for "Norman Remer 8-inch mirror spreadsheet" rather than "12".

Norman Remer's PDF guide, "Making a Refractor Telescope," is a 12-page document that provides a comprehensive introduction to the process of building a refractor telescope. The guide is designed for individuals with limited experience in telescope making, offering a clear and concise overview of the necessary steps and techniques involved. Remer's guide covers a range of topics, including:

Since its publication in 2006 by Willmann-Bell, this book has become a staple for DIY astronomers.

The F-Ratio: For a DIY refractor, an f/12 to f/15 ratio is ideal. Long focal lengths significantly reduce chromatic aberration (the "purple fringe" around bright objects).

📄 About the “12 New” PDF request

If you’ve seen a file named something like Remer_Refractor_12_new.pdf, it’s likely:

What is this document?

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