Object catalogue handling Initial TCS commands Twilight Sky-flats Seven Star Calibrate Focusing the Telescope Finding Guide Stars and guiding TCS/Auto-Guider interface commands Command dictionary for UltraDAS Object catalogue handling USER>incl <virgo> - Includes a user catalog named virgo.cat, stored in /int/cat. Check that the catalog has been loaded properly by listing it from the TCS using the command: USER>out term To add objects to the catalog type: SYS> object name 12 20 30 -10 5 40 J2000 SYS> add to move to the object type: SYS> next - for the last one entered or SYS> gocat name However, objects added with the object/add sequence are passed directly to the object catalogue held on the TCS computer, and are not stored on the system computer. TO write a catalogue back to disk use: USER> output file int:[cat]newfile which saves the file newfile.cat on a disk also visible to the system computer as /int/cat. Initial TCS commands USER>show focal - Show the focal station setup. If not set to Cassegrain/IDS, run the command SYS>startobssys from the pink observing window. USER>focus 14.45 - Set focus to a 'good' value. USER>calibrate last - Load the last TCS pointing model. Twilight Sky-Flats Point on a blank field. Suitable fields are listed below e.g.: USER>gocat blank3 BLANK1 04 25 46 +54 09 03 B1950 BLANK2 13 04 33 +29 50 49 B1950 BLANK3 16 47 52 -15 17 44 B1950 BLANK4 19 19 09 +12 22 05 B1950 BLANK5 21 26 54 -08 51 41 B1950 BLANK6 23 54 08 +59 28 18 B1950 SYS> run 10 "skyflat 10sec" - and take exposures. Seven Star Calibrate If the telescope pointing the previous night was acceptable, no additional action is requires as you already typed: USER>cal last To update the pointing coefficients run the seven star calibrate procedure. The values for temperature, humidity and atmospheric pressure should be updated before as they are used to calculate refraction. Check the TV probe is in the center (see IDS mimic, command tvxy 500000 500000). USER>TEMP 6.0 (local outside air temperature) USER>HUMI 0.1 (local outside relative humidity e.g. 10%) USER>PRES 770 (atmospheric pressure) USER>CAL You can abort calibrate any time with 'control Z'. Center all seven stars using the TCS HANDSET in XY-mode on the slit next to the TV cross hair. Turn the TV gain down each time when you move to the next star. When the telescope is tracking again, carefully increase the gain. If the pointing solution is ok (rms < 5-6"), type "Y" to accept. Focusing the Telescope To determine the best telescope focus select a flux standard and take e.g. 10 sec exposures at different telescope focus positions. Use focus steps of 0.1mm, 0.05mm if the seeing is very good. The focus should not change from night to night. Set the focus to the value were you obtained the smallest FWHM measured in spatial direction using the command: SYS> focus 14.45 Finding Guide Stars and guiding Start up a LAT session to LPVS3, login as GSS and select int->cas configuration. To search for a guide star, use the following commands: $ gss GSS> config int cass GSS> rot 180 GSS> sea 13 04 33 29 50 49 B1950 GSS> exit $ type output.gs The guide star search program is called 'gss'. Before searching for guide stars you need to specify the optical configuration and the rotator position. The result is written to a file called 'output.gs'. It basically contains a list with x-y coordinates for the autoguider probe. Select a star of 12-14th magnitude for guiding and move the probe by: SYS> autoxy 430000 580000 Now set the exposure time and expose the autoguider to check for possible guide stars: SYS> autotime 1000 - set integration time in ms. SYS> field After the field operation the stars are identified by numbers on the autoguider display. Select a star for guiding which isn't saturated and avoid hot pixels using the command: SYS> guide on star 1 - pick brightest detected object and guide The guide loop is closed automatically. After the observation, before moving to the next object we recommend to stop guiding: SYS> guide off - turn guiding off USER> autoguide off TCS/AutoGuider interface commands SYS> focus 14.45 - set telescope focus SYS> rotate sky 180 - move CASS rotator to 180 degrees SYS> gocat 12+30 - go to faint pointing grid star SYS> gocat N12+30 - go to bright pointing grid star SYS> offset arc -30 30 - offsets telescope with reference to the demanded pointing position by -30 and 30 arcsec SYS> autotv [on|off] - continuous readout mode SYS> field - do a field and search for potential guide objects SYS> guide on star n - pick "n"th brightest detected object and guide SYS> guide on pixel x y - guide on at position x,y on auto-guider CCD default is to specify x y = -1 -1 which cause A/G to guide on current guide star location SYS> guide off - turn guiding off SYS> autotime t - set integration time "t" in ms. Command dictionary for UltraDAS Command dictionary for UltraDAS

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