Parameters in grismspec.dat are listed one entry (filter or grism) per line. They are written format free and have to be given in the right order. Comment lines can be placed at any place in the file. They are recognized by a ``;'' in the first column.
Each entry must start with the keyword in the image header which is used to identify the image. Next, the value for this keyword and the corresponding image type is given (d= direct image, s= spectrum).
The subsequent information in an entry depends on whether the entry refers to a direct image or a grism image.