There has been a lot of confusion about pointing terminology.

CSO pointing model: the telescope pointing model used and written as a black box

• has already been corrected for aberration/nutation
• is in current epoch coordinates (e.g. J2007.34)

Instrument-specific correction to pointing model

• ??? also referred to as 't terms'
• is offset between CSO pointing model and real locations
• should be a function of alt (and maybe az)
• is recorded in "RPC" files
• is in units of distance on the sky: delta-RA and delta-DEC, or delta-ALT and delta-AZ will be in the same units, while if they were in coordinate units delta-RA and delta-AZ would have to be scaled by 1/cos(DEC) or 1/cos(ALT) respectively

FAZO and FZAO: Fixed Azimuth Offset and Fixed Zenith Angle Offset

• these are ambiguously defined in the pipeline code
• ???? FAZO/FZAO include both the functional instrument specific pointing offset and any manual changes made at the telescope [manual only relevant to 2007 observations]
• ???? or are these JUST fixed offsets, and the instrument specific corrections are not included? Either way, how can I separate out manually-applied fixed offsets from fitted-model offsets?