Everything posted by LROC Data Node Manager
This post seems to be discussing two topics: how to process WAC data and how to extract elevation/height information from WAC data. To process WAC EDRs into something you can extract meaningful, scientifically valid information, you should download the USGS ISIS software. This will allow you to calibrate the WAC EDR products and if needed, map project the observations. To extract elevation/height data, you either need to start with a digital terrain model (either derived from geometric stereo observations or an instrument like LOLA). Image data in and of itself does not provide that information with out performing some complex processing. For the moon, two excellent sources of elevation/height information are the LOLA products and the WAC GLD100 product. For higher resolution height/elevation, there are NAC DTM products but there is limited coverage of the lunar surface (< 1%).
First and foremost - one should read the documentation for the LROC PDS RDR products ( http://lroc.sese.asu.edu/data/LRO-L-LROC-5-RDR-V1.0/LROLRC_2001/DOCUMENT/RDRSIS.PDF) and when available, the README file for an individual product family (for the Eratosthenes DTM refer to http://lroc.sese.asu.edu/data/LRO-L-LROC-5-RDR-V1.0/LROLRC_2001/DATA/SDP/NAC_DTM/ERATOSTHNS1/NAC_DTM_ERATOSTHNS1_README.TXT), before attempting to use any of the data products. In your particular case, you are attempting to read elevation data from the ortho-rectified image, not from the actual DTM product. For each NAC DTM product the LROC team generates, there are numerous files created: DTM, ortho-rectified images, slope map, confidence map. If you download and ingest the actual Eratosthenes DTm, you should be able to read the elevation values. It can not be stressed enough, please read the documentation first, which should preclude false starts such as this.
Can you provide some specific details regarding which file you are ingesting and which isis 3 command you are using to ingest the file with? That will help us debug the issue you are having. In tests using pds2isis, the displayed values (as seen in ISIS qview) corresponded to the expected values of elevation (in meters).