RPHOT - Photometry Reduction Software

RPHOT is a software package that I wrote around 1990 to acquire and process the raw data from the Optec SSP family of single-channel photometers into final, reduced, standardized magnitudes, and to do plots, curve fitting, period-finding, and other useful tasks. The program was written for the old IBM machines we had available to us at Cabrillo, and written in FORTRAN and Assember to run at the command line.

Earlier plans to make a Windows version of RPHOT are on the shelf - the student who planned to do this has moved on. RPHOT will remain a DOS command line program. In fact, the field itself has moved on I no long plan to support the RPHOT package. For the record, however, I'll keep this webpage for now...

RPHOT Overview

RPHOT until recently was distributed exclusively by Optec, Incorporated, which makes a growing array of ruggedly constructed and very high quality instruments made for the serious amateur and professional astronomy market. RPHOT has a number of modules:

DTAK: talks to the SSP photometer through the SSP3A ISA card. The latest Optec photometers now do all communication through the serial port and no longer need the SSP3A card. Optec has their own module, SSPDATAQ, which creates the text file of counts output by the photometer, in RPHOT-compliant format.

IREX: pairs up variable/comparison/check stars for differential photometry, identifies all-sky photometry, and does sky subtractions.

FREX: does final reductions to standardized or instrumental magnitudes after applying first order, second order extinction corrections, and tranformations to standard magnitude systems. It makes use of included standard star catalogs.

RPLOT: produces plots of magnitude vs time, with or without smoothing over user-selected time intervals, fits periodic or polynomial curves to the data, measures the times of minima or maxima, determines extinction correction terms from linear regression fits plotted to the screen, and plots counts vs. time for for fast-mode data such as occultations.

There are also modules for measuring and plotting Jurkevich periodigrams to Fourier analyze light curves, for determining the airmass given a star's coordinates and time of observation, for producing ephemerides for eclipsing binary stars using included catalogs of eclipsing stars, and other options.


Current Progress on WinRPHOT

01/21/05: C#.NET will interface with my FORTRAN modules once they are suitably modified. IREX and RPLOT are the two most complicated modules to upgrade. I'm about 70% done with the modifications to IREX. Eric's put together a first draft UI for the RPLOT module. He's also done a generalized graphic routine which we will include in WinRPHOT.

Oct '07: Bad news - Eric moved on. I've had my plate full with other projects. And, I've not heard a great demand for the WinRPHOT package. There's no further progress on a Windows version, and no current plans to do so. I'm a one-man astronomy department here and priorities are calling me away. However, the command line version still works quite well.

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