This is a summary of normal IGRINS use for observers at the McDonald 2.7m telescope

1 IGRINS & Atlas Computer Set Up
2 Taking Flats (~1 hour needed)
3 Dome Opening Procedure
4 Start of Night
5 Setting Up Guiding
- 5.1 On-Slit Guiding
- 5.2 Off-Slit Guiding (for experts only)
6 Using the DTP
7 !! 300s SKY Frame each night !!
8 Identifying A0V Stars
9 Changing the Slit Position Angle on the Telescope
10 Closing Procedure
11 Legacy Notes

IGRINS & Atlas Computer Set Up

On Atlas
1. Log in with IGRINS account.
  1. Ask for username and password if you do not already know it.
2. Open Browser (Firefox has all of these bookmarked).
  1. In the IGRINS bookmarks folder open the following:
    1. SNR Quicklook (http://192.168.2.2/?obsdate=date): For looking at the spectra taken throughout the night to verify observations are reaching the required SNR. Note: The date at the end of the link must be updated to the current observing date from the bookmarked date.
    2. Nightly Observing Record (https://igrins-status.firebaseapp.com/night/date) : Keeps track of all of the IGRINS observations taken in a night. Note: The date at the end of the link must be updated to the current observing date from the bookmarked date.
    3. House Keeping Package: Keeps track of the instrument health--always--monitor to ensure all of IGRINS parameters are within acceptable ranges.
    4. IGRINS Digital Night Log: A google spreadsheet that will auto populate throughout the night per frame taken.
    5. What Target is IGRINS Observing?: Tracks the coordinates put into the TCS, the position angle of the slit, and over-plots the slit onto a 2MASS K-band image of the target. Best if used in parallel with a finder chart, but can be helpful for verifying rotation orientation and pointing.
  2. Open weather related monitoring pages from the McDonald weather links tab in the bookmarks. We recommend the Mt. Lock Live Weather, the McDonald Observatory Clear Sky Chart, and AccuWeather or Windy for cloud monitoring.
3. Open the VNC Viewer to view the IGRINS computer.
  1. Applications → Internet → VNC Viewer
  2. Connect to the IGRINS ICC. Should only require a double click, but you can follow the steps below if needed.
    1. From atlas use the internal ip address 198.168.2.2 but if connecting from outside the network use the external ip address (might need to use McDonald VPN): 198.214.229.87
    2. Port: 5902
    3. Username: admin
    4. Password: [ask someone if you don’t know it. It is the standard IGRINS password]
  3. Input the IGRINS computer password.
On the VNC-viewed IGRINS Computer (ICC):
1. Open a terminal window.
  1. > cd ~/igrins_admin
  2. > sh ./run_icshub.sh
    1. The IGRINS Hub should appear--verify that the date of observation is correct.
    2. If “Check Mount” is Failing:
      1. Open a new terminal window.
      2. > cd ~/igrins_admin
      3. sh ./mntrun
      4. Enter the IGRINS computer password.
      5. Click the “Check Mount” button in the IGRINS Hub, which should hopefully return the status to “Okay”.
        If “Fail” again: remote into IGRINS detector computers. If not able to login [add link], check the computers are turned on in the electronics rack. If they are turned on, there is likely an issue with the fiber optic cable--contact observing support.
    3. Click “run HKP” & verify the health of the instrument.
2. Open a new terminal window.
  1. > cd ~/igrins_admin
  2. sh ./run_all_scripts.sh
    1. The terminal for this should take up the entire length of the screen--it runs multiple scripts with outputs that are hard to read otherwise
    2. This script runs multiple scripts that allow for the use of the firebase apps that update throughout the night (see the IGRINS Bookmarks tab on Atlas Firefox)--these improve quality of life greatly but are not strictly required.
3. Open a new terminal window.
  1. > cd ~/igrins_admin
  2. sh ./run_file_transfer_daemon.sh
    1. This script manages the file transfer between the ICC and the IGRINS computer. Do not close the pop-up window!
On Atlas, Launch the TCS. Make sure you are using the '2.7m Cass F/9' mount model.
In the IGRINS Hub click “run TCSProxy”.
1. Verify that the top of the pop-up says “TCSProxy HJST 107””.
2. Verify that the coordinates from TCSProxy match those in the TCS window on Atlas.
  1. If all of the coordinates read as 0’s, then the Colossus computer might have failed. Phone for observing support locally.
In the IGRINS Hub click “run SCP” and “run DTP”.
1. On the SCP (Slit Camera Viewer), click “Single” in the Detector Control (box 13).
  1. Verify that a slit camera image is produced (box 5).
2. On the DTP (Data Taking Package) click “Test Exposure” on the bottom left under the K-Band image box (box 1)
  1. Verify that an image is produced in H- and K-Band
  2. Verify that the TCSProxy coordinates are not all 0’s (that the connection between IGRINS and TCS is good).
    1. If all coordinates read as 0’s, then the Colossus computer might have failed. Phone for observing support locally.
3. If for whatever reason, either of these fail, phone for help!
To enable sounds from the IGRINS observing computer in the observing room:
1. Open a terminal in Atlas
2. > cd igrins_tools
3. > cd play_msg
4. > /home/igrins/miniconda3/envs/igos3/bin/python play_msg.py (running the script the enables the notification sounds).
On the Atlas computer open the following:
1. The MONET sky camera (pink “SKY” button pinned to the taskbar).
2. The HJST dome floor camera (pink “HJST” button pinned to the taskbar).
3. The HJST slit camera (pink “SLIT” button pinned to taskbar).
4. The Night Report (enter name info and add report content throughout the night).

Taking Flats (~1 hour needed)

Go out in the dome
1. Go to the old control room (Colossus Control Room) and press each of these buttons:
2. Go to the console and press "Reset". You will hear a click as the breaks preventing the telescope from moving are released. There should be no messages on the TCS now.
3. Point the telescope to Zenith
  1. Go to the TCS, click the "Next" menu, click "Zenith", and click "Yes" on the warning message that pops up.
  2. Click "Go Next" at the top of the TCS window.
  3. Push the Autoslew button in the dome to move the telescope to the Zenith.
4. Use the console to open the telescope mirror cover
5. Set up IGRINS and telescope for taking calibrations
  1. Raise the east platform so you can reach the top of IGRINS
  2. Open the shutter on top of IGRINS is for taking flats
  3. Be sure to secure the window cover arm using the velcro.
  4. Lower the east platform back down.
6. Move the telescope to the Flat position
  1. Go to the TCS, click the “Next” menu, click “Flat”, and click “Yes” on the warning message that pops up.
  2. Click “Go Next” at the top of the TCS window.
  3. Push the Autoslew button to move the telescope to the Flat position.
  4. Use the yellow hand paddle to move the upper wind screen all the way down to reveal the full flat screen.
7. Use the TCS to move the telescope dome to the “Park” position
  1. Go to the TCS, click the “Tools”, click “Park”, and click “Yes” on the warning message that pops up.
8. Turn off all the lights in the dome.
In the Observing Room:
1. In the DTP on the ICC:
  1. Click the “FLAT-OFF” button below the K-band image plot (box 1).
    1. Click “Yes” on the pop-up that appears (this just fills in the Object Name and Exposure Time in the DTP).
    2. This will fill the Seq Bar with 10 x E frames, change the object name, object type, and set the exposure time (boxes 7, 3, and 6).
  2. If there are 3 flat lamps working you will need 30 second exposures, if all 4 are working then 20 second exposures will do.
  3. Change the exposure time to 30 seconds (box 6; if not already set to that).
  4. Change the Object Name to “FLAT 30s” (box 3; if not already set to that).
  5. When ready to take the FLAT-OFFs, click the “Start/Resume Sequence” button (box 8).
2. FLAT OFF frames should take about 10 minutes to complete. Computer will say "H finished", "K finished", “Sequence finished” when they are done.
Back to the dome to turn on the Flat lamps for FLAT ON frames
1. Move the rolling stairs from their stowed location to on platform east under the telescope
  1. Ensure the location you place the rolling stairs is clear of the telescope or off the moving platform entirely
2. Raise the platform using the yellow hand paddle until you will be able to reach the plug for the flat lamps on the side of the telescope
  1. !! Make sure you do not get close enough to bump IGRINS with the raising platform !!
3. Plug the flat lamp power cable into the side of the telescope, see images below
In the Observing Room:
1. In the DTP on the ICC...
  1. Click the “FLAT-ON” button below the K-band image plot (box 1).
    1. Click “Yes” on the pop-up that appears (this just fills in the Object Name and Exposure time in the DTP).
    2. This will fill the Seq Bar with 10 x E frames, change the object name, object type, and set the exposure time (boxes 7, 3, and 6).
  2. If there are 3 flat lamps working you will need 30 second exposures, if all 4 are working then 20 second exposures will do.
  3. The peak counts per FLAT exposure should be between 6,000 and 10,000 counts. Inspect the FLATS in DS9 to ensure that this was achieved. You can also check the peak flux counts in the SNR quicklook tool (see 1.b. in the Setup above).
  4. Change the exposure time to 30 (or 20) seconds (box 6; if not already set to that).
  5. Change the Object name to “FLAT 30s” (box 3; if not already set to that).
  6. When ready to take the FLAT-ONs, click the “Start/Resume Sequence” button (box 8).
2. FLAT ON frames should take about 10 minutes to complete. Computer will say "H finished", "K finished", and “Sequence finished” when they are done.
3. Turning off Flat Lamps/stowing wind screen
4. If you changed the FLAT exposure time in the FLAT ON process, then retake the FLAT OFF exposures with the same exposure time.
5. Close the telescope mirror cover on the console so nothing falls on the mirror when moving the upper wind screen
6. Move the upper wind screen back to its original position using the yellow hand-paddle

c. Unplug the flat lamps from the side of the telescope.

d. Stow the ladder on the side of the dome floor (off of the lift platform), out of the way.

Dome Opening Procedure

To startup the telescope follow the dome opening procedure. Be sure to monitor the weather conditions and abide by the dome closing conditions while observing!

If all prior steps were completed, then the remaining steps are:

Turn off the dome lights and passage lights.
Prop open the doors on both sides of the dome.
Open the Louvers using the Air Controller panel by the east door.
Open the slit by holding down the "Dome Open" button on the console. This will take a few minutes. You will hear a clank when the dome is fully open. Once the slit is open, you can let go of the button.
Press and hold the "Cover Open" button on the console to open the mirror cover. You will hear a sound when it fully opens (note the light indicator no longer works, so listen for the sound). Once it is open, you can let go of the button.
On the TCS computer or atlas, select Tools → Enable Dome Automation

Start of Night

Check and zero the telescope pointing
1. If TCS has not been reset since the prior night of observing, your pointing will be easier to find than if TCS was reset during the day.
2. Follow either of the directions outlined here:
  1. How to zero the telescope pointing in TCS
  2. Telescope Pointing Procedure
3. Note: Since IGRINS has returned to McDonald Observatory in late 2024 the pointing has been difficult to obtain because the zeroes are often far off when TCS is reset. Be prepared to spend up to several hours in the beginning of the night pointing (particularly spiraling around using the paddle in the SCV), especially if you are not an experienced user of McDonald HJST. Our advice to make pointing easier is to pick a star near zenith that has several surrounding bright stars (see example 29 Peg) because if the telescope is very far off in pointing nearby bright stars clustered by dim stars are easier to identify in the slit view camera images than clusters of all dim stars. Remember to take into account the slit rotation when looking at finder charts!
Focus the telescope
1. Use the yellow hand paddle in the observing room to adjust the telescope focus
2. Make sure there is a star near the center of the SVC field of view that is bright enough to measure the FWHM of its PSF but not so bright it saturates the detector.
3. It might be useful to set up a spreadsheet to record your focus values vs. star PSF FWHM
4. Select minimum and maximum range of focus values to check [Note: Generally between 58,000 and 65,000], start at the lowest range
5. Start at the minimum and loop through the following procedure (there is hysteresis in the system so we always step through the same way)
  1. Step up in values of 200
  2. Take a 4 second slit view camera image.
  3. Click the star to measure its FWHM [put in image of the plots we use to measure this from the SCV]
  4. Keep an eye on the shape of the star’s PSF and make sure it looks reasonable [show an example of the tail that can appear when things are out of focus]
  5. Write down a table with the focus value the FWHM of the star
  6. Repeat the above steps, filling up your table, until you reach the maximum focus value to check or you are confident you are out of focus
6. Find the focus value that gives the best FWHM (it might be useful to plot your table in a spreadsheet)
7. Go back to the minimum focus value
8. Slowly in small steps raise your focus value until your reach the value that gave you the best FWHM
9. Take another exposure of your star and double check you get the expected FWHM
10. If you are confident the PSF FWHM is good, you are now in focus!

Note: If there are large changes in temperature over the night and/or you notice stellar PSFs in your SVC images look bad, you might want to refocus

Setting Up Guiding

On-Slit Guiding

Our guide to on-slit guiding using the SCV GUI can be found here. This guide includes the guiding reset procedures in the event the target falls off of the slit while spectra are being acquired and if the target does not slew to the correct nod position on the slit.

Observers should always be monitoring the target position on the slit during on-slit guiding. Targets centered on the slit during observations produce better quality reduced 1D spectra!

Off-Slit Guiding (for experts only)

Using the DTP

The Data Taking Package is used to acquire IGRINS spectra throughout a night of observing. Check out the simple instructions on how to use the DTP here and for a more detailed description of all the button options check out the DTP GUI outline here.

!! 300s SKY Frame each night !!

The PLP requires a 300s SKY frame for deriving the wavelength solution. To take a SKY frame:

Move the telescope to the zenith.
Click SKY at the bottom of the DTP window, next to the other calibration buttons.
Click ‘Start Sequence’ to take one E exposure.
Continue observing after you have the SKY frame.

Identifying A0V Stars

Kyle has written several A0V Star worklists that can be used to identify nearby A0V stars throughout the night. Each worklist has to be uploaded to your TCS user account (only once!) for you to be able to use them throughout the night. You can download the worklists from here the Wiki or from here on Google Drive to upload them to TCS. (upload directions would be helpful here--20241206)

The worklists are organized by magnitude, so if you notice there are not many available A0V stars nearby your target try using a fainter magnitude worklist!

Changing the Slit Position Angle on the Telescope

Move the telescope to Zenith
1. Using the TCS select Next → Zenith and click yes on all of the pop-up windows.
2. Click “Go Next” at the top of the TCS window.
Slew the telescope to Zenith by holding down the Autoslew botton on the dome floor console.
Ensure the rolling ladder is not on the raising platform.
Use the yellow hand paddle to raise platform east until you can comfortably reach the mount that connects IGRINS to the telescope.
1. Not so high that IGRINS or the electronics rack will hit the platform floor!
Get the wheel attachment from the red tool box on the opposite side of platform east (see image in step 7 below; found near the ladder that brings you to the second floor in the dome).
There are four screws on the IGRINS rotator plate that need to be loosened.
1. 3 should have star-like handles (boxed in pink in the image below) you can manually loosen (unless a Darrin has been applied recently… then good luck)
2. The last screw is a large hex screw (on the corner of the rotator plate near the calibration unit; boxed in orange in the image below) that needs to be unscrewed using the large hex wrench (pointed to with the red arrow in the image below) kept on the top of the dome control console.
Once all of the screws on the rotator plate are loosened, attach the wheel attachment to the rotator peg on the rotator plate.
1. This can be a little fussy to attach because the wheel and peg have interlocking parts, so a headlamp or flashlight can be helpful for getting the right orientation of the wheel.
2. You’ll know the wheel is in position when it is near flush against the rotator peg.
Turn the wheel to rotate IGRINS in the appropriate direction.
1. This requires some elbow grease!
2. If you have difficulty moving IGRINS with the wheel alone, attempt applying some pressure on the edges of the electronics rack to loosen the rotator plate.
3. DO NOT PUSH ON THE CRYOSTAT
Encoder settings for different position angles can be found here.
1. Once you think you are close to your desired rotation position check the value on the encoder and adjust as needed.
Once you reach the desired position
1. Remove the wheel and return it to the tool box.
2. Screw in the 3 star-handled screws on the rotator plate. They should be tight!
3. Use the wrench to tighten the last special screw and return the wrench to it’s found location.
Verify that the cooling cables are NOT UNDER THE PLATFORM before using the hand paddle on the dome floor console to lower platform east.
1. This may require that you lower the platform a little, jump off, adjust the cables, and continue lowering the platform (repeat as needed).
In the control room:
1. In the ICC on the SCV GUI change the the rotator value (box 10) and on the TCSProxy change the rotator value.
2. Resume observing!

Note: the on sky drift for guiding while observing is always higher when IGRINS is not in PA = 90 deg, so you may have to adjust the frequency that the guiding offsets are sent to the TCS (box 15 in the SCV GUI).

Return IGRINS to the stow position at PA = 90 deg at the end of the observing night.

Closing Procedure

Some of these things can be done in any order, and some things should be done in an explicit order. When the order doesn’t matter, the text is in teal.

Move the telescope to Zenith
1. Using the TCS select Next → Zenith and click yes on all of the pop-up windows
Close the IGRINS window cover
1. Rotate IGRINS back to a PA of 90 degrees, if needed
2. Raise the east platform using the yellow hand paddle
3. Close the IGRINS window cover using the handle
4. Be sure to secure the handle using the velcro strip
Stow the telescope
1. Using the TCS select Next → Stow and click yes on all of the pop-up windows
2. Press and hold the button on the dome floor console to move the telescope to the stow position
Close the Mirror Window Cover
1. Using the button on the Colossus Console (the console in the dome with all the red buttons). You should hear the motor stop when it is fully closed.
Close the dome
1. Using the button on the Colossus Console. There will be a loud sound when it finishes closing.
Put any wind screens that are over the dome slit back to their stow positions using the hand paddle
Park the dome
1. Using the TCS select Tools → Park Dome and click yes on all of the pop-up windows
Close the dome doors
Close the dome vents
1. Using the control panel on the East side of the dome near the door
E-stop the telescope
1. Using the button on the Colossus Console
Turn on the passage lights (only once dome is closed fully)
1. Using the button on the Colossus Console
From the control room
1. Log-out of ATLAS
  1. Click the power button on top right hand side of the lower monitor
Turn off the heater in the observing room

Legacy Notes

Note: RA and DEC that are saved in the digital log, from the DTP screen are the 'Next' coordinates on the TCS. The coordinates displayed in the SCP are the current epoch coordinates and these propagate the the FITS headers.

Note: When guiding, 'send AG offsets to TCS' must be selected for offset commands to be sent to the telescope.

Note: You need at least one 300s sky frame each night for the PLP to work correctly. If you will not get one of these for your science, then get one to help with reductions. Any OFF frames for the night that are ~300s can also work in place of a dedicated sky frame--just note in digital log.

IGRINS

Observing Cookbook at McDonald HJST 2.7m