Attempting to re-interpolate the nav/scan timing on CASI data for flight 97/14 using aznav, the program seems to edit the HDF files correctly but then doesn't release the file lock (gives error "There are still open AIDs" on closing). Everything seems fine but then it causes azgcorr to hang part-way through. It is believed this is because the old data is HDF 3.3 format (rather than HDF 4) and there are compatibility problems.

Per Dec 2008's steering committee, we need to investigate the methods of doing atmospheric correction with a view towards implementing it as a standard service.

Suggested code to use is ATCOR or MODTRAN. ENVI FLAASH is also a possibility but said to be less good..

Related tickets:

• #109 - output of ground coordinates in azgcorr

Contacted by Dr Li (Lily) Zhang re: some CASI data from '97 and various issues:

• azgcorr version
• use of azgcorr parameters
• necessity of DEM with low altitude differences (20-30m, max 70m)
• ENVI + HDF loading, finding the geolocation
• Using GCPs?

Also attempting to fix remaining timing errors in the dataset Lily's using (GB97/14).