Double clicking on the image icon will bring up this panel.
The first four fields on the left are the corner points of the input image. As per IDL convention the longitude
values are in degrees east.
The next three fields match the map_image keywords.
Minimum value : Data points with values equal to or less than this value will be treated as missing data, and
will be set to the value specified by the MISSING keyword.
Maximum value : Data points with values equal to or greater than this value will be treated as missing data, and
will be set to the value specified by the MISSING keyword.
Missing value: The pixel value to set areas outside the valid map coordinates. If this keyword is omitted, areas
outside the map are set to 255 (white) if the current graphics device is PostScript, otherwise they are set to
0.
The image interpolation method is chosen by the radio buttons. See the IDL on-line help to see specific details
concerning these two types.
The compression field controls the accuracy of the results from the image interpolaton. The default is 4 for
output devices with fixed pixel sizes. The inverse projection transformation is applied to each ith row and column.
Setting this keyword to a higher number saves time while lower numbers produce more accurate results. Setting this
keyword to 1 solves the inverse map transformation for every pixel of the output image.
The scale value is the pixel/graphics scale factor for devices with scalable pixels (e.g., PostScript). The default
is 0.02 pixels/graphic coordinate. This setting yields an approximate output image size of 350 x 250. Make this
number larger for more resolution (and larger PostScript files and images), or smaller for faster, smaller, and
less accurate images.
An alternative to removing the image is to select the hide radio button. If a layer is hidden it will remain in
the layer manager but will not be plotted.