For best results, display this file with a fixed space font. This disk contains data acquired by the JPL TOPSAR instrument over the Galapagos Islands of Isabela and Fernandina. The files here include both 8 bit per pixel uncalibrated radar brightness (files containing the string "sigma") images and 16 bit per pixel digital elevation data (files containing the string "topo2"). The 16 bit data are signed integers with an increment of 10 cm (0.1 m) per data number (dn). The size of the complete Isabela mosaic is 8644 pixels by 14444 lines, thus we have subdivided it into 16 sub-images. Each of these subimages is 2161 pixels by 3611 lines, and is denoted by a suffix of 01 thru 16 appended to the file name.They fit together as follows: ------------------------------------------------- | | | | | | | | | | | 01 | 02 | 03 | 04 | | | | | | ------------------------------------------------- | | | | | | | | | | | 05 | 06 | 07 | 08 | | | | | | ------------------------------------------------- | | | | | | | | | | | 09 | 10 | 11 | 12 | | | | | | ------------------------------------------------- | | | | | | | | | | | 13 | 14 | 15 | 16 | | | | | | ------------------------------------------------- The Isabela mosaic data are set on 10 m postings, as are the Fernandina data. In addition, a set of averaged data of both islands at 40 m postings is included and denoted mosaic.sigma and mosaic.topo2. The correlation and error estimate maps are provided, and denoted mosaic.corr and mosaic.err. Each of these is an 8 bit per pixel image at the same 40 m postings as the two-island mosaic files mosaic.sigma and mosaic.topo2. The scales for these are as follows. Correlation is represented as one percent per dn, and error estimates as 10 cm per dn. Thus the values in the correlation image range from 0 to 100 while in principle all values are possible in the height error estimate image, with full scale (255) representing 25.5 m error. Also included is a GIF format file (mosaic.gif) showing the complete mosaic in image form at the same dimensions as the error maps, and a second GIF format file (galmap.gif) which presents the data in map coordinates with annotation in kilometers and latitude/longitude. File definitions and sizes: Name Contents Pixels Lines ----------------------------------------------------------------- isabela.sigma.xx Isabela brightness, 10 m postings 2161 3611 isabela.topo2.xx Isabela elevation, 10 m postings 2161 3611 fernandina.sigma Fernandina brightness, 10 m 3114 3298 fernandina.topo2 Fernandina elevation, 10 m 3114 3298 mosaic.sigma Both islands, brightness, 40 m 2334 3750 mosaic.topo2 Both islands, elevation, 40 m 2334 3750 mosaic.gif Both islands, gif format image 2334 3750 mosaic.corr Both islands, correlation, 40 m 2334 3750 mosaic.err Both islands, error estimates,40 m 2334 3750 galmap.gif Both Islands, map coordinates,40 m 2982 3915