You may need to adjust the dial on the incandescent lamp between filters to achieve manageable exposure times. With STE3/4, keep exposure times ≥1s to allow the shutter time to open and close.
== Observing recipes: on sky ==
The pointing model of the 1.0-metre is greatly improved in recent years, but is not quite perfect. It may be necessary to point to a bright star near your target to allow the TCS to calculate the pointing offset in each part of the sky. One set of offsets will be
applicable to a range of positions.
=== Determining pointing offsets using a bright star ===
Follow the facility start-up procedure in Section~\ref{sec-facstartup}.
# Using the Astronomical Almanac or Sutherland Almanac, select a bright star ($\sim 4^{\rm th}$~mag) near your science target (ideally within RA~30m and dec~10°).
# Check that the target and bright star selected are within the observing limits given in Section~\ref{sec-limits}.
'''On the TCS''':
# '''Initialise''' the XY-slides.
# Move the '''guide mirror into the beam'''.
# Click "TARGET" and type the RA & Dec of the bright star into the appropriate boxes, then click "SET" and "CLEAR". The coordinates will appear in yellow on the monitors above the TCS and on the observing floor to help you point to the target.
# Type the '''equinox''' of the bright star coordinates into the "SET EQUINOX" box and press "ENTER" on the keyboard.
== Current known issues (last updated Nov 2013)==