Some Hawk bands are noisy to the point of uselessness. For example band 71 (1403nm), raw data from Nigg Bay line 3 (attached)

Also see over-water spectrum produced in level 3 image:

Spectrum cannot really be used for anything much - there is no means of quality controlling the data

Data issue occurs over more than one flight, possibly there are sensor problems with some Hawk bands. See eg. Latera band 71, similar to Nigg Bay:

Inspection of the FODIS output for Hawk (level 1b) suggests that it is uncalibrated (or otherwise incorrect). Spectrum generated (taken from Nigg Bay line 3) is:

(X-axis is band number for Hawk, not wavelength). Graph shape should match solar spectrum (see eg http://fsf.nerc.ac.uk/img/g37_grph.gif) and doesn't.

Peter Land suggested altering azgcorr to allow L1 files to be opened read-only. Currently they are opened read-write, which causes problems if they are on / were copied from read-only media.