## Changes Introduced in V1.8-4

The following describes the most significant changes which occurred in the AST library between versions V1.8-3 and V1.8-4:

1. The FitsChanFitsChan class has a new attribute called DefB1950DefB1950 which can be used to select the default reference frame and equinox to be used if a FitsChan with foreign encoding contains no indication of the reference frame or equinox.

2. A bug has been fixed in the FitsChan class which could prevent astWriteastWrite from creating a set of FITS headers from an otherwise valid FrameSetFrameSet, when when using FITS-AIPS encoding.

3. A bug has been fixed in the FitsChan class which could cause astReadastRead to mis-interpret the FITS CROTA keyword when using FITS-AIPS encoding.