At the top of the IQE form, you will notice a large field for the FITS file name. This will be the file on which statistics are performed, and all locations, both entered and reported, will be relative to this file and in image pixel units. The use of the entire FITS file as the area from which to perform statistics is not recommended, due to the nature of the calculations. Use the raster image in the lower right of the form as a guide to the meanings of these variables. The edge of the data is always ignored, due to various edge effects found in CFHT CCD's.
Selection is via radio button.
The FWHM values are usually computed on the maximum pixel's X and Y coordinate vectors. This may be useful for spectroscopic data. After selecting the action desired, and the set of FITS files to apply this action to, pressing the Accept button will result in the desired action being performed. As each file is processed, it will be listed in a popup window. As files are listed in this popup window, those that have been saved to tape will be surrounded by parentheses, while those that have not been saved to tape will appear simply as the file name.