The threshold level for automatic determination of the dekker extent.
This is the percentage (of maximum intensity) below which the spatial
profile is to fall before being classified as outside the dekker.
In general an Arc frame will be used to establish the dekker limits,
and a value of 80% will suffice.
The default value is 0.8 (i.e. 80%).
ECHOMOP-Echelle Data Reduction Package
Starlink User Note 152
2003 July 14
Copyright © 2003 Council for the Central Laboratory of the Research Councils