AIPS HELP file for OVERLAP in 31DEC19
As of Tue Dec 18 4:53:17 2018
Type: Adverb (scalar)
Use: To specify how overlaps are handled in imaging
Null value: <= 0
Taken to mean do nothing about overlaps.
IMAGR........Fourier transforms and Cleans uv data with wide-field,
interactive TV, and data weighting options.
IMAGR will review each field (if OVERLAP > 0) and see
if any components from it also fall in any other field.
If so, it will restore them there as well. Note that
this is done by brute force convolution since the
components of one field do not fall on the grid points
of another field and is therefore fairly slow.
In addition, if OVERLAP > 1, IMAGR will use a sequence
of Cleaning designed to reduce the instabilities
inherent in Cleaning an object from more than one
field. This functions only if DO3DIMAG > 0 as well.