Astronomy Page

Articles and software related mostly to telescope making. Despite the page title there’s no actual astronomy related material here. Maybe someday.

New technical article (February 2006).

Article on interferometry mathematics and algorithms (Adobe Acrobat format). This explains the mathematics behind interferometric data reduction techniques.

 Fringe analysis software (Updated February 2006):

I now have two R packages for interferogram analysis. Both are free, open source, and portable to at least Windows and Unix/Linux platforms. Rfringe is a package for fringe tracing, with a simple GUI and the ability to manage projects containing multiple interferograms. The package “zernike” includes routines for Fast Fourier Transform (FFT) based interferogram analysis and for the analysis of Phase Shifted Interferometry (PSI).

zernike downloads:

· Redirect to sources and windows binaries.

Rfringe downloads:

· Gzipped tarball. Choose this for a Linux/Unix installation.

· Windows binary. “Pre-compiled” package for Windows installation.

· Zipped source files. This is identical to the Linux tar.gz file, in a more Windows friendly format.

· Manuals. There are two manuals, in Adobe Acrobat format. One provides formal, R style documentation of all functions in the package. The other is an installation and user guide describing the Rfringe GUI. These manuals are also in the other archives in the doc subdirectory. And yes, the manuals take up most of the space in these files.

Older articles and software of potential practical interest.

• Cassegrain baffle layout. Technical paper (Adobe Acrobat format.)
• Companion spreadsheet for the design of cassegrain telescopes and baffle systems. Quattro Pro format (13kb zip).
• Same spreadsheet in Microsoft Excel format (15kb zip).
• A semi-automated Foucault test.

Older articles of purely theoretical interest.

The following articles are in Adobe Acrobat (pdf) format.

• Modal analysis of Foucault test data. Revised 2 Mar. 2002. Linear regression analysis (least squares) applied to Foucault test measurements. This is the sensible way to analyze Foucault test data if you collect sufficiently large amounts of data. If you’re still cutting out paper masks don’t bother. (Warning: long and technical).
• Extended source Foucault. Technical notes written mostly for my own benefit discussing how to account for an extended source in numerical simulations of the Foucault (and related) test. Extra credit to anyone who figures out the unstated physical assumption I’m making.

Click on the links above to view the paper or download the companion spreadsheet. The Quattro Pro and Excel versions are functionally and visually identical, so take your pick. Please email me at mpeck1@ix.netcom.com with comments or questions. Spreadsheets and papers are Copyright © 1999 - 2008, M.L. Peck. Rfringe and zernike are partially copyright by the author as described in the main source file, and are distributed under the Gnu General Public License.