The C versions are all in one file and a Makefile is unnecessary. Simply compile with one line such as gcc -lm solar.c to generate an executable a.out, and then rename a.out to whatever you prefer. C language versions accept command line input. Execute a program without input to get a help prompt. The Fortran version prompts for input, but is otherwise almost identical to the C version. It would provide a template if you wanted to create other Fortran programs with color image output. To compile the Fortran use g77 solar.f or ifc solar.f depending on which compiler you prefer. The program is written in standard f77. Neither the C nor the Fortran programs here have been optimized for fast execution, and they appear to run in similar times when processing very large files. The program "solar" will take several minutes on a 3 GHz Intel Processor PC with 1 GB of memory to process the full Rowland table because it generates a Lorentzian for each line and integrates over all contributions to find the flux at each pixel. The program colorspec is much faster and it simply averages over the flux in the table within the window of each pixel. The PPM file format used here is standard ASCII and can be read with an editor for diagnostics. Most, but not all, image display programs will accept this format. The conversion to TIF in an image processing program such as Gimp should be lossless. TIF versions of the sample ppm files are provided here. The uncompressed JPG versions given here offer 10x smaller file sizes because of the encoding, but with some loss of quality.