PS1 Seeing Observations:

A series of ongoing observations are being made explicitly to analyze the seeing conditions for the PS1 telescope. The first several nights of data were taken with the RoboDIMM located in the PS1 parking lot; on Dec. 9 it was moved to the PS1 entry balcony on level 1. Efforts were made to simultaneously observe both the same and different stars that the DNSM DIMM was observing. At times, we were also able to acquire simultaneous observation from the PS1 of the same star. Different symbols show which star was being observed. Different line colors separate the DIMM measurements.

RoboDIMM Howto

​CTIO DIMM documentation

RoboDIMM Measurements

===December 3, 2009===

RoboDIMM located on jibcrane pad in parking lot. RoboDIMM measurements worse than DNSM and GPC1 measurements for most of the night

• ​Seeing Plot
• ​RoboDIMM data

===December 7, 2009===

RoboDIMM located on jibcrane pad in parking lot. RoboDIMM measurments were better than GPC1 measurements but worse than or equal to the DNSM measurements.

• ​Seeing Plot
• ​RoboDIMM data

===December 9, 2009===

RoboDIMM located on L1 entry balcony. RoboDIMM measurements were worse than DNSM measurements but better than GPC1 measurements for most of the night. Winds from the N-NW.

• ​Seeing Plot
• ​RoboDIMM data

===December 11, 2009===

RoboDIMM located on L1 entry balcony. Note that this night shows particularly good correspondence between the DNSM and RoboDIMMs seeing measurements. Both DIMMs show better seeing than the GPC1 measurements. Light tradewinds throughout the RoboDIMM measurement period

• ​Seeing Plot
• ​RoboDIMM data

===December 16, 2009===

RoboDIMM located on L1 entry balcony. The wind during the RoboDIMM measurements was ~5 m/s out of the N-NW. During the second set of GPC1 images both the DNSMand RoboDIMM were running but not able to collect data.

• ​Seeing Plot
• ​RoboDIMM data

===December 24, 2009===

RoboDIMM located on L1 entry balcony. The wind during the RoboDIMM measurements was light (<3 m/s) and varied in direction from W to NW. The target stars for both DIMMs were in the SE so data was collected pointing away from the wind.

• ​Seeing Plot
• ​RoboDIMM data

===December 28, 2009===

RoboDIMM located on L1 entry balcony. RoboDIMM located on L1 entry balcony. The wind during the RoboDIMM measurements was light (<4 m/s) from the N-NW. The target stars for both DIMMs were in the SE so data was collected pointing away from the wind. GPC1 data is corrected for airmass.

• ​Seeing Plot
• ​RoboDIMM data

NOTE

From Dec. 28, 2009 onwards, DNSM data are corrected to zenith. Also, from this date, DNSM and RoboDIMM data are calibrated to PS1.

The format of the data files is:

DNSM

time_UT time_msec name r0 zenith_distance fwhm_uncorr fwhm_corr fwhm2ps1

RoboDIMM

time_UT time_msec name_1 name_2 r0 fwhm fwhm2ps1

===December 30, 2009===

RoboDIMM located on L1 entry balcony. Wind from SW at < 2 m/s. Target stars in the SE.

• ​Seeing Plot
• ​RoboDIMM data
• ​DNSM data

===December 31, 2009===

RoboDIMM located on L1 entry balcony. Wind from W at < 3 m/s. Target stars in the SE.

• ​Seeing Plot
• ​RoboDIMM data
• ​DNSM data

===January 3, 2010===

DNSM not operating. RoboDIMM located on L1 entry balcony. Wind from W-SW at < 8 m/s. Target stars in the SE.

• ​Seeing Plot
• ​RoboDIMM data

===January 6, 2010===

DNSM not operating. RoboDIMM located on L1 entry balcony. Wind from W at < 10 m/s. Target stars in the SE.

• ​Seeing Plot
• ​RoboDIMM data

===January 7, 2010===

DNSM not operating. RoboDIMM located on L1 entry balcony. Wind from W at < 10 m/s. Target stars in the SE.

• ​Seeing Plot
• ​RoboDIMM data

===January 8, 2010===

RoboDIMM located on L1 entry balcony. Wind from W at < 8 m/s. Target stars in the SE.

• ​Seeing Plot
• ​RoboDIMM data
• ​DNSM data

===January 10, 2010===

RoboDIMM located on L1 entry balcony. Wind from W at < 6 m/s. Target stars in the SE.

• ​Seeing Plot
• ​RoboDIMM data
• ​DNSM data

===January 19, 2010===

RoboDIMM located on L1 entry balcony. Wind from NNE at < 1 m/s. Target stars in E & SE

• ​Seeing Plot
• ​RoboDIMM data
• ​DNSM data

===January 20, 2020===

RoboDIMM located on L1 entry balcony. Wind from NW at < 1 m/s. Target stars in E & SE

• ​Seeing Plot
• ​RoboDIMM data
• ​DNSM data

===January 21, 2010===

RoboDIMM located on L1 entry balcony. Wind from N at ~ 5.5m/s. Target stars in E & SE

• last couple of minutes we lost the star due to it being eclipsed by PS1

• ​Seeing Plot
• ​RoboDIMM data
• ​DNSM data

===January 22, 2020===

RoboDIMM located on L1 entry balcony. No wind. Target stars in E & SE

• ​Seeing Plot
• ​RoboDIMM data
• ​DNSM data

===January 23, 2020===

RoboDIMM located on L1 entry balcony. Wind from S-SW at < 5 m/s. Additional tarp hung to block wind. Target stars in E & SE

• Operations halted at 8 after the wind increased and moved to due W.

Howto

Setup

• Adjust tarps for anticipated wind (there's an extra in the wood chest)
• Remove RoboDIMM cover *CAREFULLY* so as not to dislodge finder (remember carabiner at bottom)
• Check to see that the leveling bubble is still mostly within the circle (close is okay)
• Retrieve telescope cables, camera controller, power strip, keypar, and stool from L1

Telescope

• Release alt brake, flip telescope, attach keypad, RS232 connector, and 18vDC pwr (tuck all cables under tripod)

Camera

• Set controller on stool, attach camera cable *BEFORE powering camera controller*

Laptop

• Set on camera controller, attach white cable from controller to LPT1, and serial from telescope (tape these together) *Plug GPS in USB port; set receiver in the open
• Turn on power strip (then switch telescope ON and plug in controller)
• Boot laptop but if the two larger LEDS along the top are not green and orange, respectively, the connector is not working. This is BAD. Gently try to reconnect the power supply a couple times. If Tom is there, get his help.
• Press cancel at login screen
• Double click NMEATime icon
  • Click the GPS Signal Quality tab (bars must be blue; GPS Locked LOCKED)
  • Click Update PC Clock Now
  • Close NMEATime window

Telescope Alignment

• Get a star in the finder (there are 4 speed buttons on the keypad)
• With the keypad:
  • Use down arrow to select "Align" press Enter
  • ALTAZ press Enter
  • 1 Star press Enter
  • Level base (should be) press ENTER
  • press ENTER, then scroll (with arrows) to align star (probably Aldebaran)
  • In the flip mirror viewport the star should be aligned so the lower image is centered on the crosshairs of reticulated eypiece
  • Turn the flip mirror knob

Running SBIG software (CCDOPS)

• Double click the CCDOPS icon
• There will be a message "Trying to Establish Link with Camera"
• If a link cannot be established, unplug controller, gently reseat all camera connections, power up and try again.
• Click on the Focus button; a dialog window ill come up with and exposure time of 0.25 sec. This is appropriate for the bright stars we're currnetly using; click okay
• If the force is with you you'll get a double image centered in the field
• If not, use the keypad on the lowest speed (bottom button) to adjust their position. (It does not have to be perfect.)
• No image? Check the flip mirror.
• Close CCDOPS (if there are messages about cooling ignore them)

Running RoboDIMM

• Click the Newtest_robodimm2.exe icon (looks like a dome)
• Check Auto Measure Enable checkbox
• Click Expose CCD button
• If there is a message about a telescope error, reseat the telescope connection to the laptop (the serial port). You may also have to cycle power to the telescope (and repeat the alignment).
• Confirming Operation:
  • If there are two spots inside a flashing white box the odds are RoboDIMM is happy
  • In the lower left of the window there will be output:
    • Last Seeing Data should have a time that's fairly recent
    • dx ~= 90 and dy ~= 0 (These values refer to the orientation of the prism and should not change unless the cover is dislodged. If it is, adjst dy by loosening the thumbscrews and rotating the cover.)
    • Last Strehl Ratio for Left/Right ~= 0.5
  • Leave the platform gently

Operation =

• Record wind speed, direction, and ops start time
• Check for a flashing box/star images ~10 min intervals

End of Night

• Click Quit button
• Turn telescope OFF and unplug controller
• Telescope: unplug keypad, RS232, and 18 vDC
  • Release alt brake, tip so camera is on top, wrap cord carefully
  • Bag carefully; lightly cinch straps opposite finder; clip carabiner
• Laptop: pull serial, unplug LPT1; check the time to make sure it's not way off
• Controller: unscrew camera (black cable)
• Data is in C:\dimmdata2002\D1test_seeing_lab.log
  • Open with double click, hightlight and copy the night's data; paste into a notepad file (icon in lower bar)
  • Save as MM-DD.txt (maybe leave off 0's because win98 is a bit dim) on F: (usb memory stick)