eXcalibrator

Current Version is 1.0.2.0

eXcalibrator calibrates image color by using the NOMAD1 or SDSS database to identify stars in your image that should be white.  The program then computes the correction factors to apply to the green and blue channels.

To install, just download and unzip eXcalibrator.zip into your desired folder and create a shortcut for eXcalibrator.exe.

If you have any problems or suggestions please don't hesitate to email me. There is an email link under the Help menu.

Download the complete installation. (4.67 MB)

Download only the latest .exe file. (421 KB)

Download only the documentation (.pdf) file. (4.25 MB)

View the documentation .pdf file online. (4.71 MB)

Revision History

1.0.1.0... Aug 29, 2009 With 16-bit images, some programs place the value, 32767, in the FITS header for the keyword BZERO.  eXcalibrator now looks for 32767 and 32768.

1.0.2.0... Sept. 1, 2009 On startup, eXcalibrator now informs the user if a program update is available.  After downloading, it will be necessary to exit the program to unzip and install the new executable. It may be necessary to go to the web page to download a new documentation (PDF) file.

Bug Fix... To avoid divide by zero errors, a Minimum Star Value has been added. The brightness for red, green and blue must all be above this value to include the star in the calibration. The minimum value is initially set to 50... anything less than 50 to 100 is probably too dim to be useful.

1.0.2.0... Feb 10, 2010 No software changes... just an organizational rewrite of the documentation into clearer setup and workflow sections. An example workflow was added, showing how to use eXcalibrator's results in an image processing program. Thanks goes to Neil Fleming for his work on this rewrite.