The command line and the observing commands

This page is part of the ING document INS-DAS-29: Operations manual for UltraDAS

This section introduces commands that may be given at the SYS> prompt. The interpreter for those commands is a Unix shell.

Commands by category

UltraDAS has a suite of commands that each do one observation:

Each of these operates the camera to make the observation, collates FITS-header data from around the observing system and saves the observation in one archiveable FITS-file. Run, arc, flat and sky do the same observation, but they are separate commands because they each record a different type of observation in the FITS header (at the OBSTYPE keyword). Please try to use the correct command for the exposure type: it makes the archived observations more valuable to the community.

For each single-observation commands there is a multiple-observation equivalent: multrun, multarc, multbias, multdark, multflash, multflat and multsky.

Each of these does a series of similar observations. UltraDAS optimizes the series by starting each observation as soon as the previous one has read out. Hence, the multiple-exposure commands typically have two runs in progress at a time.

The command glance makes an observation but holds it in memory and does not record it on disc. This command is sometimes useful with the automatic image-display to check targeting and exposure level without wasting disc space.

The command scratch takes an observation in the same manner as run and records it in a scratch file. The commands is useful for building scripts that need to operate on an observation in a known place.

You can create an archiveable file from a glance observation using the keep command. You can do the same for a scratch file using the promote command.

The command rspeed changes the readout speed. There are two choices, called "fast " and "slow". There is no way to change the clear speed of the camera.

The bin command sets binning factors in the x and y directions. Set the factors factors back to 1, 1 with the same command to turn binning off.

Readout windows are supported. See the separate page on windowing. You may also need to see the section on coordinate systems.

There are three commands that affect observations which are already running.

Finish and newtime have no effect if an integration is not in progress. Further, they do not affect cycles of a multrun that have not yet begun.

If you try to retime an observation to less time than it has already integrated, newtime behaves like finish.

Exploiting the command shell

UltraDAS commands run from the shell in the same way as normal Unix commands like ls: they are sub-processes of the shell. This means that they can be manipulated using the normal Unix techniques.