PROJECT NAME Nili_Patera_Caldera HIRISE SOURCE IMAGES ESP_013582_1895 ESP_020940_1895 TECHNICAL CONTACT INFORMATION NAME JOEL MUETING INSTITUTION UNIVERSITY OF ARIZONA Products are tied to MOLA elevations. Elevation range for this project: VALID_MINIMUM = 118.79 m VALID_MAXIMUM = 768.91 m SOCET SET NGATE was used to extract terrain. Post spacing in DTM is 2 m. NOTE: Total RMS ==> 0.22212 px RMS x ==> 27.006 m RMS y ==> 6.9389 m Z error (difference from MOLA) = 4.08 m, stdv 10.27 NAMING CONVENTION: DTM PRODUCT_ID = aabcd_xxxxxx_xxxx_yyyyyy_yyyy_Vnn where aa = DT, indicating it's a DTM product b = type of data E = areoid elevation R = radii c = projection (others are possible but these are the important ones) E = Equirectangular P = Polar Stereographic d = grid spacing A = 0.25 m B = 0.5 m C = 1.0 m etc. xxxxxx_xxxx = orbit number and target code from SOURCE_PRODUCT_ID[1] yyyyyy_yyyy = orbit number and target code from SOURCE_PRODUCT_ID[2] V = letter indicating producing institution U = USGS A = University of Arizona C = CalTech N = NASA Ames J = JPL O = Ohio State Z = Other nn = 2 digit version number ORTHOIMAGE PRODUCT_ID = XSP_xxxxxx_xxxx_CCC_S_NN_ORTHO where XSP_xxxxxx_xxxx = HiRISE source observation ID (mission phase_orbit number_target code) CCC = color content RED = visible RED, 1 band image IRB = 3 band enhanced color (IR, RED, BG) S = grid spacing (comparable to the DTM naming convention above) A = 0.25 m B = 0.5 m C = 1.0 m etc. NN = a sequence number to distinguish between orthorectified images from the same HiRISE observation that may be created from different DTMs. ORTHO indicates that the image has been orthorectified KNOWN ARTIFACTS These are known artifacts present in some, but not all, HiRISE DTMs. They may not be present in this DTM! Look at the terrain shaded relief to detect these before using the DTM! - Boxes Some DTMs have square areas that are usually about .5-1 m different in elevation from the surrounding areas. These are artifacts of the processing algorithms used in Socet Set ((c) BAE Systems). There may be goups of these boxes. They are almost impossible to edit, so the user should look for such artifacts in a terrain shaded relief map before using the DTM for analysis. - CCD seams A HiRISE image is made up of 10 individual images, stitched together along their long edges. In a DTM, these seams can be visible as long lines. These seams are difficult to remove. - Faceted areas Areas that were very bland (low contrast) or deeply shadowed with low contrast and low signal may have a "faceted" look to them. Terrain in these areas is not trustworthy.