The grid translations went innermost, i.e. mounted on the head, so a grid
position turned with the spindle. At SLS the grid is an Aerotech xyz that the
spindle is mounted ON, so the mounting order is base -> grid -> omega -> chi ->
phi -> sample and a grid position is independent of omega.
Identical to the previous chain at omega = 0, which is every grid scan collected
so far, and correct rather than incorrect when it is not.
A head-mounted stage exists too - the Smargon translates, and that is what
helical uses - and would sit on the other side of omega. Only the base stage is
modelled for now, which is the one actually used; the comment says so.
Measured: dials.import reads a master with the new chain.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
leonarski_fandClaude Opus 5
5e05515165