\parindent 0pt
\parskip 0.3cm
%\section{Logging Data}
\section{LOGGING DATA}

\subsection {Logging Observations}

All observations taken at prime Focus or with the IDS/FOS spectrographs are
logged by an automatic system based on an IBM PC. This system is interfaced
to the MIMIC display and the Information Display from which it takes all the
information relevant relevant to the status of instrumentation and telescope
at the time of observation. Among the items logged are the UT, exposure time,
RA, Dec, Autoguider Probe position, filters and central wavelength of 
spectroscopic observations. The log is currently kept on the hard disk of the
PC and written to a dedicated line printer. It is intended to send the
data to the VAX as well, and from there to the UK. A print copy of the log is
collected in a binder which remains in the INT Control Room. The observer will
get another print copy to take home.

\subsection {Reading the ICONA Meteorological Instruments}
\label{ch14:ICONA}
 
 The Stevenson screen containing 4 thermometers and a thermo- 
hygrograph is located about 100 metres east of the INT Dome. The 
rain gauge is a few metres to the north-east of the screen and 
is normally kept locked. The replacement charts for the 
thermohygrograph are kept in the cupboard in the TO Office and are 
changed every Monday morning by the TOs. 
 
 On rare occasions it may be necessary to read the rain gauge. 
This is usually done on the first day of the month. 
 
 Open the bottom flap of the rain gauge using the Yale key. 
Take care because the measuring cylinder is only resting inside 
and is not fixed in any way. Remove the cork from the nozzle and 
operate the valve to let the accumulated rainwater run out. Quite 
often, the volume will be greater that the capacity of the 
measuring cylinder so the valve must be closed before the level 
of the water reaches the 10.0 mm mark. NOTE THAT THE MAXIMUM 
READING IS 10 AND NOT 100 MM. Record the reading each time 
until a pink, viscous liquid comes out. This liquid is intended 
to prevent evaporation and it is less dense than water. Wait 
until it has settled out on top of the water and take the reading at 
the bottom of the liquid mensicus. Note the reading, adding it to 
the others (if any), empty the cylinder and cork the nozzle. 
Replace the cylinder, lock the gauge and record all readings along 
with the time of observation on the ICONA form. 
 
\subsection{Telescope Focus} 
 
Now that the dome-induced seeing is under control, the largest 
contribution to the image size in the telescope focal plane
seems to be the telescope focus. In 1.0 arc second seeing, with a 
1.0 arc second slit, a deterioration of telescope focus by 0.05 mm
decreases the efficiency of the telescope by 10-20 per cent; in 0.6 arc second 
seeing, it would cost 30 per cent. 

Focus in the direct TV mode. First adjust the TV gain to give an 
image which is easy to see but not saturated.  
Telescope operators should determine focus by taking an average 
of at least 3 and preferably 5 independent measurements. Take the mean
and write down the result in the TO's log.   Once set the telescope
tracks with temperature.   However if the seeing improves it is wise
to focus again later in the night. 
 
\subsection{Seeing Measurements} \label{ch14:seeing}
 
 
 To ensure that we have a method which enables us to compare 
one night with another at the Cassegrain focus please adopt the 
following. One of the seeing measurements must be taken at the 
zenith around midnight - or after the dome has been open for 
several hours. 
 
\begin{enumerate}
\item Choose a star which appears in or near the field  being observed. 
 
\item Focus the telescope (see Section 12.2). 
 
\item Integrate for 128 frames in SUM mode using the slit viewing Grinnell TV. 
 
\item Adjust the TV gain to give an unsaturated image. (The profile 
 of a saturated image shows a flat top). 
 
\item Select MENU (RESTRICTED PROFILE) using the joystick or the 
 SELECT button on the Grinnell control box. 
 
\item Make the Grinnell seeing measure in RA. If the turntable has 
 been rotated use the RA guide button to see where RA lies. 
 
\item Repeat twice more and carry out the whole procedure 4 or 5 
 times per night. Record in the NA logbook. 
 
\item Note the zenith distance and focus for the measurement in the TOs
log. 
\end{enumerate}


\subsection{Windspeed Measurements}

The INT Dome should not be left open if the windspeed exceeds:

{\bf 22 metres/sec = 80 km/hour = 50 mph} 

The wind speed measurements and direction indicators on the Meteorological
Console are taken from the mast 100 metres to the East of the
building.   They are reliable except when the instruments are frozen solid.

\subsection {Telescope Operation Logbook}
 
 This log is used to provide 
information with regard to the telescope operational activities. 
 It is kept in a standard Stationery Office hard-covered manuscript book.
 
 The following notes describe the way in which the log is to be used. 
 
\begin{enumerate} 
\item Start each day in the log on the right hand page and head it 
 with the date in the following format: 1985 August 22/23 
 
\item Note in the Log any action or occurrence concerning the T/S, 
 Dome, Instruments or Computer Systems. 
 
 Notes should be brief and to the point, thus: 
 
 2100 - Dome opened JNG

 2130 - IPCS Failure, fault under investigation DJI
 
 Any detailed information should be put in the appropriate log 
 with the reference to it recorded in this log. 

 NB EACH LOG ENTRY SHOULD BE INITIALLED 
 
\item Fault cards should be filled in in the usual way and a brief 
 note of the fault also made in this log:
 
 2200 - Telescope tracking problems. Fault card submitted VR 
 
\item The log begins at the start of each day and ends when observing 
 finishes the next morning. 
 
The following notes give an example of what 
 a day's log may look like: \vspace{1.0cm}

\begin{tabular}{lll}
Time &\multicolumn{2}{c}{1985 Mon/Tue Sept 15/16}
 \\ \hline
 0930 & Flat field terminated & DXC \\ 
 1030 & A and G Box fault investigation started & RDA \\ 
 1040 & telescope control software modified & ACC \\ 
 1115 & A and G Box fault repaired - OK & RDA \\ 
 1300 & Telescope access parked for work at Prime & KGM \\ 
 1345 & Prime focus work complete. T/S zenith parked & KGM \\ 
 1440 & Duty Technician checks OK & EJM \\ 
 1700 & FOS CCD filled & VR \\ 
 2100 & Dome opened & VR \\ 
 0300 & Noisy dome motor, fault card submitted & VR \\ 
 0700 & Dome closed, T/S Closed down. Flat field running& VR \\ 
\end{tabular}
\end{enumerate}

\vfill
\eject
