== Frequently Asked Questions == This page is designed to complement the [wiki:Help] page. If you ask us one of the questions on this page, you're likely to get an answer copy/pasted from here. If you have read this answer and are still unclear, please mention that you've looked at this page when you contact us so that we don't just give you the same answer again. === APL === * [wiki:FAQ/aplaz What is the difference between APLCorr and Azgcorr?] * [wiki:FAQ/aplmask What do the values in my mask file represent?] * [wiki:FAQ/aplmissingscans Why does my mapped image have black bars across track?] * [wiki:FAQ/apldemformat What format should my DEM be in when using aplcorr?] * [wiki:FAQ/aplunrecognisedopt I get the error "unrecognised options on command line:", what does this mean?] * [wiki:FAQ/aplostn02gridshift Where can I get the grid shift file needed for apltran for describing the Ordnance Survey National Grid projection?] * [wiki:FAQ/aplunknownmapprojection I get the error "Unknown map projection: You will have to fill in the projection name and datum in the map info in the .hdr file yourself." when defining a projection using Proj4, what should I do?] === Azgcorr === '''PLEASE NOTE THAT AZGCORR IS NO LONGER BEING SUPPORTED AFTER 10 MAY 2015''' * [wiki:FAQ/azgcorrbend When I geocorrect data, Azgcorr stops and complains that the flightline has a turn in it - how can I process my data?] * [wiki:FAQ/processingspeed Is there any way to speed up geocorrecting my data or to reduce the file size of the geocorrected files?] * [wiki:FAQ/lev3blank Why are my geocorrected files much bigger than my level 1 files?] * [wiki:FAQ/lev3upsidedown Why are my geocorrected files upside down? Do I need to manually rotate images to make north "up"?] * [wiki:FAQ/lev3colourpixels Why do my geocorrected Eagle/Hawk files have unexpectedly red/green/blue/yellow pixels?] * [wiki:FAQ/azgcorrExpired My azgcorr has expired, where can I get a new one?] * [wiki:FAQ/azgcorrDEM What is the azgcorr ASCII DEM format?] * [wiki:FAQ/demtoosmall Why does azgcorr say "DEM does not enclose the image" and then stop, and how do I fix it?] * [wiki:FAQ/hdfsizelimit My image data is in a .bil file not an HDF, how do I geocorrect it with azgcorr?] === Hyperspectral Data and Deliveries === * [wiki:FAQ/hyperatcor I have no ground truth reflectance data - how can I convert my radiance to reflectance?] * [wiki:FAQ/hyperxmltags What do the tags in the line and project information XML files mean?] * [wiki:FAQ/converttofloat How do I convert the data type of BIL files to floats?] * [wiki:FAQ/level3unzipping Why are the level 3 files so large when they are unzipped?] === LiDAR Data === * [wiki:FAQ/lidarasciiformat What is the file format for my ASCII LiDAR data files?] * [wiki:FAQ/las2ascii How do I convert between LAS and ASCII file formats?] * [wiki:FAQ/lidartools Do NERC-ARF supply software to process the LiDAR data?] * [wiki:FAQ/dsmdtm Do NERC-ARF generate a DTM/DSM from LiDAR data?] === RCD Camera deliveries === * [wiki:FAQ/rcdorthorectification How can I orthorectify RCD imagery?] * [wiki:FAQ/eventfileformat What is the content of the delivered event file?] === Level 1 Data === * [wiki:FAQ/bandwidth What are the bandwidths/band centres of my data?] * [wiki:FAQ/units My data values are much larger than I was expecting. What units are the data in?] === Datums and Projections === * [wiki:FAQ/ostn02 If I load my ARSF data with a GPS dataset in a GIS, they don't match. Why not?] Otherwise known as, why is British National Grid projection not where it should be, and what is OSTN02? * [wiki:FAQ/projections What is the difference between an ellipsoid, a geoid, a datum and a projection?] === Data Access === * [wiki:FAQ/downloadftp How do I download delivered ARSF data via FTP?] * [wiki:FAQ/dataaccess How do I access the ARSF data archive? ] * [wiki:FAQ/acknowledge How do I acknowledge ARSF data in presentations/publications?]