Prepared by: John Shobbrook

(Please email amendments or suggestions to sbrook@mso.anu.edu.au)

RUNNING CICADA

• Log On to Monsoon under your own account name.
• Open a new Xterm or Shelltool window, at the prompt type cicada & <Enter> this will open the basic [Cicada v4.0.14] tool bar.
• On the Cicada tool bar click on Start Observing. Click on WFI
• Enter the observers name, check □ Automatically archive raw data - Click on OK
• When the Cicada Control window opens, click on Close Shutter (if the green ‘Shutter Closed’ button does not appear, click on ‘Actions’ – ‘Initialise Controller’. Ignore the warning message).
• Click on Controller - click on Readout Mode select Fast
• Click on Instrument Controls, click on Filter: F_40 Initialise the filter wheel by clicking on Get Filter Position. Close the window by clicking on Dismiss
• At the start of each new observing run - NOT each night, click on Tools - click on Start Teldisk... - click on Clear Disk, click on OK Clear the disk (this will clear the previous observer’s data from the hard disk and create a new directory for your data) - click on Quit Teldisk
• Check that the ‘Output Image Directory’ name is correctly set by clicking on Options – click on Preferences - in Directory enter /data/monsoon1/cicada/username
• Insert an appropriate entry in ‘Prefix’ to e.g. ccd - wfi

Whilst in Options → Preferences, select …

q Show messages window at startup

q Reset number of exposures to 1 after each sequence of >1 exposures

q Toggle binning when switching from no-save to save

• Flush count = 1
• Screen Numbers … GIT = 0 Pipeline = 0 Gsfind = 0 Ximtool = 1

(The left monitor is ‘1’ – the right monitor is ‘0’)

· Focusing Parameters … Steps 5 First focus position 0.001 Position step 1.000

· Star profile radius (pixels) 10

· Click on Apply

· At the top of the Preferences Window, click on General, click on Image Display and Scaling

• The ‘Display Options’ setting are …

Scaling Algorithm …

Adaptive Median Sample size = 1000 %of image to readout before scaling = 25

Contrast adjustment = 0.50 Num SDs tolerance before rescaling = 0.10

• Click on Apply if you have adjusted these settings - click on OK

WFI

• In the Cicada control window click on Tools - Click on, Start GIT this will open the CICADA_Ximtool window and the Graphic & Imaging Tool Window.
• Click on the ” icon towards the right of the ximtool window, to open the [Ximtool Control] window.

TELESCOPE SETUP

• (Delay this step if you are taking Dome Flats) Open the dome shutters.
• At the dome console ensure that the ‘Dome Lights’ ‘Dome’ ‘Telescope’ and ‘Tracking’ pushbuttons are switched ‘ON’ (upper button pressed IN) – leave the key switch on.
• Set the Auto – Slew/Set rotary switch on the dome console to Slew/Set
• Lower the telescope using the Declination – Slew ‘S’ button to about -70° (beyond the SCP) raise the floor level, remove the lens cap and store it on the bracket behind the dome console.
• Lower the floor, raise the telescope to the vertical using the ‘N’ slew button.
• Set the Auto – Slew/Set switch to Auto

FILLING THE DEWAR

(N.B. Take Dome Flats before filling the dewar to avoid LN² spillage).

• In Cicada click on Controller click on Show Temperatures
• Record the pre-fill dewar temperature as shown in the FOCALPL ‘Actual’ column, record the dewar vacuum as displayed on the WFI.
• In the Dome - remove the lens cap BEFORE filling the dewar to prevent LN² spillage.
• Press the large red STOP button to the right of the dome console.
• Fill the dewar from the LN² bottle. If the pressure is below 7, connect the orange spiral airline attached to the pier to the LN² bottle ‘Vent’ plug to reduce the filling time.
• Press the "Emergency Stop Reset" button (illuminated beside the STOP button)
• In Cicada click on SDSU click on Read Temperatures
• Record the post-fill dewar temperature and vacuum.
• Fully lower the observatory floor.
• Turn off all light within the dome, The incandescent light switch is to the right of the balcony door, the fluorescent light switch is on the dome below the shutter. The red lights are controlled from the dome console.

N.B. If you need to use the shutter windscreen, the ‘raise’ and ‘lower’ control buttons are located on the dome beneath the shutter opening.

BIAS FRAMES

· In the Cicada control window set…

· Object Name: BIAS

· Exposure Type: □ BIAS - □ Save and Display

WFI

· Exposure Options - number of exposures: 5

· Click on Options, click on Show Regions Window Check that ‘region 1’ is highlighted with a blue box and that the X Y Width and Height settings are set for the full CCD. X-offset (XO) = 0, Y-offset (YO) = 0, Width = 8392, Height = 8272.

· Set the Overscan Columns to 0 (This Overscan option is for the 2.3m DBS Astromed controllers. The WFI SDSU controllers have overscan and bias regions preset).

· Click on Dismiss - Click on Expose

Bias frames should display between 2,500 ~ 4,500 counts

(The standard deviation of bias frames can be calculated by using GIT - Load the bias frame into ximtool – using the left mouse button drag a box onto the image - click on the

Statistics Icon (Bar Graph) - the standard deviation should be between 2 and 3. Clear the box by right clicking on the box and choosing ‘destroy’.)

FLAT FIELDS

Sky Flat preparation…

These should be taken about 15 to 30 minutes after sunset or before sunrise. The key to this is to be about 20º away from the zenith in the direction opposite to where the Sun is setting or rising. Sky Flats tend to be better than Dome Flats. As a general guide …

· In the late afternoon, slew the telescope in R.A. away from the sunset to the Sidereal Time + 1 hour. In the early morning slew to the Sidereal Time – 1 hour. In summer slew in Declination to – 20º. In winter slew in Dec to – 40º, in spring and autumn slew to about – 30º

Dome Flat preparation …

(N.B. Take dome flats before filling the dewar to avoid LN² spillage.)

· In the E.T.S. Configuration – Configure menu, set the Dome Control to Manual

· Enter the dome, ensure that the console Auto – Slew/Set knob is switched to Slew/Set

· Using the Declination – Slew ‘S’ button, lower the telescope to about -78º (beyond the SCP) (Telescope ZD = 70° as shown on the ETS monitor)

· Rotate the dome to an Azimuth of 70° (as shown on the ETS monitor) or align the red and black mark on the dome with the marks on the wall behind the dome console.

· Rotate the dome so that the dome flat screen and telescope are in alignment.

· Partially open the upper shutter to faintly illuminate the screen, turn off all dome lights.

· If you need to use dome lights, use the tungsten lights only!

Cicada settings for Sky/Dome flats …

· In Options → Show Regions Window use the X Y Width and Height settings for the full CCD. Set x-offset = 0, y-offset = 0, Width = 8392, Height = 8272.

· Object Name: Sky_Flat or Dome_Flat, Exposure Type: □ Flat

· Start taking Flats with Exposure Options set to □ Display Only

·

WFI

· Set the Overscan Columns to 0 (This Overscan option is for the 2.3m DBS Astromed controllers. The WFI SDSU controllers have overscan and bias regions preset).

· For Dome Flats start with an exposure duration of between 10 ~ 25 seconds.

· Read the counts in Ximtool and adjust the exposure duration or light entering the dome until you obtain a value of about 30,000.

· When the correct number of counts have been reached, set the Exposure Options to … □ Save and Display

· Click on Expose – take at least 5 flat fields with each filter in use.

· With Sky Flats, offset the telescope between exposures by about 2 arcmin, by switching the control room paddle to Set and pressing the ‘N’ button for about one second.

· Aim for brightness counts in the vicinity of 10,000 ~ 30,000.

DARK FRAMES (Dark current is small and dark frames are generally not necessary).

POINTING THE TELESCOPE – CALIBRATING THE POINTING

· Ensure that the Auto – Slew/Set rotary knob on the dome console is set to Auto and that the dome floor is fully lowered.

· Using the E.T.S. Configuration – Configure menu, set the Dome Control to Auto

· Click on the Motion drop down menu, click on Track

· Enter the Name (Optional) R.A., Dec and Epoch (Optional) of the target object.

· Click on Track - Take an exposure to ensure that the target has been centred.

· Click on Configuration – Calibrate Pointing, enter the R.A. and Dec of the target, click on Calibrate, click on Close

FOCUSING THE TELESCOPE

(Using the WFI Automated Focusing sequence)

· In Cicada under the Actions drop down menu, click on Do_Focus_Sequence

· Follow the prompts or refer to p. 17 of the Cicada User’s Manual

· To highlight a star, drag across it with the left mouse button then click the right-moost icon in Cicada ‘Read Marked Region from Image Tool’

· Move the focus using the “In” and “Out” buttons on the round paddle by 0.03 - 0.05 units between each image, starting at about 31.70 (as displayed on the small red LED focus readout box)

(Using the MaxIm DL autoguider CCD …)

· In the Focus Tab check the Continuous box, then click the Reset button.

· Ensure that the Subframe is set to Left = 0 Top = 0 Width = 320 Height = 240

• Set an appropriate exposure time (e.g. 10 seconds).
• In the Focus Tab, click on the Start Focus button. After the first exposure click the Abort button.

· Click the Auto button, this will place a box around the brightest star in the field.

· Click on Start Focus exposures will continuously cycle. Click on the Inspect tab.

WFI

· Focus the telescope using the In and Out buttons on the control room hand paddle.

N.B. The ‘In’ button increases the focus position value, (as displayed on the control room focus position digital display) the ‘Out’ button decreases the value.

The ‘Inspect’ Tab will display the information needed to focus the telescope including the FWHM in pixels and the amplitude (‘Max’ window) of the brightest pixel. Best focus is obtained with the FWHM value as small as possible and the ‘Max’ value as large as possible. The narrower the 3-D isometric plot, the better the focus.

The plate scale of the WFI is 0.375 arcsec per pixel, 25 arcsec per mm or 2.5 pixels per sec of arc e.g. if a star image is 5 pixels across then the seeing is 2 arcsec. The field of view covers 52 arcminutes with the diagonal being 1.2 degrees.

You can also monitor focus as you work by keeping an eye on the images. The 40-inch has astigmatism such that images are elongated at about 45 degrees from NW to SE when the focus setting is too high and from NE to SW when the focus is too low.

You can use this astigmatism to focus the telescope:

If the star images are elongated …

NW-SE => focus is too high: Press the “Out” button (LED readout decreases)

NE-SW => focus is too low: Press the “In” button (LED readout increases)

Typical focus values are in the range from 31.65 – 31.88

(Using the main WFI CCD mosaic …)

· Using the control room hand paddle, slew the telescope to the South of the chosen focus field then back North to cancel gear backlash - stop with the Declination seconds readout on “00” (use the ‘Guide’ option for fine control).

· Using the hand paddle, cancel focus backlash by increasing the focus readout with the IN FOCUS button until you are beyond your start position. Press the OUT focus button to come back down to your start position (say 32.40).

· Set Exposure Type to … □ Object and □ Display Only

· .Set Exposure Options to … Exposures 1 Duration 10 seconds

□ No pre-flush and □ No readout

· Click on Flush to clear the previous image from the CCD array then click on Expose

· Using the ‘N’ paddle button set to Guide move the telescope by 20” of arc (watch Dec change on the E.T.S monitor, declination will decrease as the telescope moves North).

· Lower the focus readout by 0.05 by using the OUT paddle button, record the focus position.

· Take a second 10 second duration exposure by clicking on Expose

· Using the ‘N’ paddle button move the telescope by another 20” of arc.

· Lower the focus readout by 0.05 by using the OUT paddle button, record focus position.

· Take another 10 second exposure.

WFI

· REPEAT the telescope move, focus and expose steps until you have taken 6 exposures at differing focus positions. (To clearly identify between the first and last image in the subsequent readout, you could also slight shift the last image in R.A.)

· For the final exposure CANCEL the ‘ □ NO READOUT’ option in Exposure Options

· Examine the displayed image, the exposure sequence will be from right to left, (if you used the ‘N’ button to move the telescope) note which focus position provides the best image – reset the focus position accordingly – repeat the focus sequence if necessary. If the image is “streaked” re-boot Cicada.

AUTOGUIDING

· If the autoguider PC has to be restarted:

1. When asked for a password, just click ‘Cancel’

2. The ‘VNC server’ is m40slave:0 Password is in the back of the 40” CCD Temp Log Book.

3. After Windows starts, click on the ‘MaxIm DL’ icon.

4. In ‘MaxIm DL’ click on Connect to connect to the camera.

5. Scroll down in the MaxIm DL window so that you can click on ‘Guide CCD’s – WFI’.

· In the Cicada Tools menu, click on Start GSFind this will open the ‘Guide Star Finder’ – this shows an outline of the main and guiding CCDs relative to GSC stars.

· Enter the RA and Dec of your target in the ‘Field’ box, enter the appropriate Equinox.

· Set the Position Angle (degrees) to 90 - set the magnitude limits.

· Click on Actions - click on Read GSC

· Use the left mouse button to drag the green CCD mosaic so that you place one of the available guiding CCD’s on top of a suitable guide star. The R.A. and Dec of the main CCD array centre will be shown in the Detector box.

(To obtain data on any star on the chart, place the cursor onto the star and press the spacebar. The RA, Dec and Magnitude of the star will be highlighted in the ‘Objects Found’ window).