OBSERVING INSTRUCTIONS FOR MzLS

Still need to incorporate the following instructions:

• Pointing the telescope, and re-zeroing the pointing using the numbers reported by MOSSTAT
• Focusing the camera
• Running the guiding loop (or choosing not to)
• Instructions for converting the JSON files into the ones that the telescope can read (what are these called?)
• Instructions for checking in the updated tile file (probably also need to add this to the DECam observing instructions)
• Coverage plots, which we've not yet ported from the DECam version

These are instructions for using the MzLS planning scripts for the nightly program. To see the Mosaic observing manual, go here: ​http://www.noao.edu/kpno/mosaic/manual.

Log on to the mzls account on the mayall-idl.kpno.noao.edu machine (which can only be done from within the KPNO network or using a VPN):

Username : mzls
Password : Ask Arjun, David, or previous observers

These environment variables define the locations of data and code:

$MOS3_DATA= -- This is where our raw data files are written
$MOS3_OBS=$HOME/mosaic3 -- This contains the observing product with code and versioned log files.
$PS1CAT_DIR=$HOME/ps1/chunks-qz-star-v2 -- Pan-STARRS1 catalogs used by the IDL DECSTAT routine for computing astrometric offsets and photometry

These path names are set in the .bashrc file, or can be set for example with "export MOS3_DATA=/mosaic3/data2/observer". The $MOS3_DATA directory must be updated to point to the current night's data.

Other directories in the home directory are:

data/ -- Link to the top-level data directory, where each night is stored in subdirectories like "20151213"
exec/ -- Cross-mount to mosaic.kpno.noao.edu:/home/observer/exec
products/ -- Code checked out from the SDSS and the DESI svn repositories

Documentation for the IDL scripts can be printed from the IDL prompt with the DOC_LIBRARY command, for example:

      IDL> doc_library,'mosstat'

Date convention

All dates in log files are set to the local date of the beginning of the night. For example, any data taken during the night of December 13/14, 2015 will be written as 2015-12-13. This is consistent with how the NOAO Science Archive timestamps and saves the raw data files.

Official Nightly Strategy

Detailed instructions for NightlyStrategy?

Updated 13 Dec 2015

Do the following to update the current NMSL scripts at any time.

• login to mayall-idl as mzls
• cd products/mosaic3
• mkdir 2015dec13
• python py/mosaic3strategy.py -t obstatus/mosaic-tiles_obstatus.fits -d 2015-12-13 -p 1 -pass 1 --moon-sep-limit 50 --start-date 2015-12-14 --start-time 02:00:00 --end-time 13:00:00-seez 1.15 -sbz 18.45 --dir 2015dec13

Rename the script, so we don't overwrite it later:

mv mosaic_2015-12-13_plan.json mosaic_2015-12-13_plan1.json mv strategy_2015-12-13.txt strategy_2015-12-13_plan1.txt

The mosaicstrategy script outputs a JSON file (e.g., mosaic_2015_12-13_plan.json in the above example). In order to produce the execution script for NOCS, run Behzad Abareshi's script:

python ./py/jnox.py --in mosaic_2015-12-13_plan1.json --out mzls_2015-12-13_plan1.sh

Then copy this output (e.g., mzls_2015-12-13_plan1.sh) to the exec directory of the observer account on the mosaic3 computer (observer@mosaic3:/home/observer/exe) which is cross-mounted as follows:

cp mzls_2015-12-13_plan1.sh /mosaic3/exec

Start uptiles running in an IDL window on mayall-idl; this will always use the most up-to-date version of the mosaic-tiles_obstatus.fits file. Once this finishes running (usually a couple of minutes), in a nocs terminal window on mosaic3, cd to exec and execute the script:

~/exec> ./mzls_2015-12-13_plan1.sh

Instructions and details for mosaicstrategy.py

written by A. Patej

mosaicstrategy.py is a Python script that can generate a nightly observing plan. It requires several Python modules:

• numpy
• pylab (Matplotlib)
• ephem (Pyephem)
• pyfits

The code is adopted from the DecamLegacy project. See those wiki pages for more information.

Selection of Pass 1, 2, or 3

It is very important to adhere to the strategy of when to observe pass 1, 2, or 3 tiles, in particular that pass 1 tiles are always in photometric good-seeing conditions. The overall strategy is outlined at MayallZbandLegacy/ObservingStrategy].

The strategy is as follows:

• Pass 1: Photometric and seeing < 1.3 arc sec
• Pass 2: Photometric or seeing < 1.3 arc sec, or all Pass 1 tiles completed
• Pass 3: Unphotometric and seeing > 1.3 arc sec, or all Pass 1 and Pass 2 tiles completed

These need not be observed in any particular order, e.g. pass 3 observations can certainly occur before pass 1.

If conditions change, then you should definitely change to a different pass. For example, if clouds begin to roll in, you should stop any pass 1 observations right away!

Running the script

At a minimum, the mosaicstrategy.py script can be run with these inputs:

-t *name of file with tile centers*
-d *UT date at start of night in format yyyy-mm-dd*
-p *portion of night (1.0, 0.5 (first half), -0.5 (second half))*
-pass *desired pass - input 1, 2, or 3*
--dir *name of the dir where the output scripts are located*

For instance, to generate a pass 3 plan for the entire night of April 26, 2015, run:

python ./nightlystrategy.py -t moasic-tiles_obstatus.fits -d 2015-04-26 -p 1.0 -pass 3 --dir obsScripts
python ./py/jnox.py --in mosaic_2015-04-26_plan.json --out mzls_2015-04-26_plan.sh

Additional optional arguments:

1. Observing conditions:
   -sb(f) *sky brightness in filter f; replace (f) = g, r, or z* in mag/sqarcsec
   -see(f) *seeing in filter f; replace (f) = g, r, or z* in arcsec
   -transparency *value of the transparency* (0-1.0)
   

2. Observing constraints:
   --airmass-limit *maximum allowed airmass, default is 2.3*
   --moon-sep-limit *minimum allowed moon separation, default is 50.0 deg*
   --moon-alt-limit *moon altitude in deg required for switching between z and g,r*
   --min-dec *Declination minimum limit for choosing tiles
   --max-dec *Declination maximum limit for choosing tiles
   

3. Custom Scheduling:
   It's possible to create a plan for a specific block of time. To do so, use the following options:
   --start-date *Date of start of observations (UTC) in format yyyy-mm-dd; overrides the default start of night, which is calculated using --date and --portion. Requires --start-time to also be set*
   --start-time *Time of start of observations (UTC) in format hh:mm:ss; overrides the default start of night, which is calculated using --date and --portion. Requires --start-date to also be set*
   --end-date *Date of end of observations (UTC) in format yyyy-mm-dd; overrides the default end of night, which is calculated using --date and --portion. Requires --end-time to also be set*
   --end-time *Time of end of observations (UTC) in format hh:mm:ss; overrides the default end of night, which is calculated using --date and --portion. Requires --end-date to also be set*
   

More complicated example using these options:
Assuming 18.2 as z-band sky brightness, 1.2" seeing in z and 1.0" seeing in r, photometric conditions (pass 1) and allowing a moon separation of 50 deg and including DESI tiles:

python ./mosaicstrategy.py -t mosaic-tiles_obstatus.fits -d 2015-04-26 -p 1.0 -pass 1 -sbz 18.2 -seer 1.0 -seez 1.2 --moon-sep-limit 50.0 --expand [[BR]]
python ./py/jnox.py --in mosaic_2015-04-26_plan.json --out mzls_2015-04-26_plan.sh

Example using custom scheduling:
To generate a plan for just two hours on the night that starts on 2015-04-26 between 05:00 and 07:00 UTC, and restricting the DEC range:

python ./mosaicstrategy.py -t mosaic-tiles_obstatus.fits -d 2015-04-26 -p 1.0 -pass 1 --start-date 2015-04-27 --start-time 05:00:00 --end-date 2015-04-27 --end-time 07:00:00 --min-dec=34 --max-dec=50 --moon-sep-limit 50.0 [[BR]]
python ./py/jnox.py --in mosaic_2015-04-26_plan.json --out mzls_2015-04-26_plan.sh

Outputs

This script will output many data files to your current directory:

1. a single text file called "strategy_mm-dd.txt", with information about all the pointings for the night (exp time, filter, approximately when they should be run, airmass, etc). There is a corresponding plot of what has been observed previously (by pass) and what you will be observing given the plan for the night: saved as a pdf, 'plot_plan_yyy-mm-dd.pdf' (gray = z, red = r, green = g). Planets and moon are plotted as well.

2. many executable script files of the form "Mosaic_Survey<tile id>.sh" for the night corresponding to the plan. There is one script file for each pointing in the plan. A single meta-script is produced that will call those ".sh" files: moasic_<ut date>_plan.sh.

3. A FITS file called "mosaic-tiles_obstatus_update_yyyy-mm-dd.fits" that is a temporary updated mosaic obstatus file that assumes all planned observations were completed. This should not be used during the run; instead use the updated tiles file obtained from running the idl program, uptiles (see section on "Creating the Updated Observing Status File" below).

Updating the "observed tiles" file

The FITS file listing which tiles have been completed should be updated throughout the night. This file is $MOS3_OBS/obstatus/mosaic-tiles_obstatus.fits. The following IDL command will monitor exposures as they are taken throughout the night, automatically updating this file:

   IDL> muptiles

At the end of the night, you should check the updated tile file into the svn repository:

   cd $MOS3_OBS/obstatus
   svn commit obstatus/mosaic-tiles_obstatus.fits --username <YOUR-NAME>

Checking the Sky Brightness, Seeing and Transparency

The observing strategy files take as input these environmental conditions for setting the exposure times to achieve the required MzLS survey depth.

From an IDL prompt, use the MOSSTAT routine to analyze the latest image on disk:

   IDL> mosstat

There are keyword options that allow you to choose different exposure numbers or CCDs within that exposure. For example, to analyze chip 'im16' of the exposure number 12345, type:

   IDL> mosstat, 12345, ext='im16'

The full documentation can be seen with:

   IDL> doc_library,'mosstat'

If the telescope pointing has gone off by more than about 30 arcsec (which happens!), then this routine will likely fail to match stars. If this happens, the operator will need to recenter the telescope.

One can also check the observing progress using the almanac command:

IDL> almanac, 10001, /noprint

will print out a summary of all the frames from 10001 to the present in a nice tabular form (widen the window). This is useful for checking how the seeing and sky brightness have varied since frame 10001, and whether one should create and upload a new JSON observing script. The /noprint just prevents the decstat output for every frame; if you want to see that, then don't use the /noprint keyword.

Creating an almanac file with the observations for the night

At the end of the night, an almanac file should be generated for the night and checked into svn.

cd products/mosaic3/logs
idl
   almanac, <START-EXPOSURE>, <END-EXPOSURE>
   exit
svn add Almanac*
svn commit Almanac*

For example, for the night of March 26/27, 2015, this is done with:

cd products/mosaic3/logs
idl
   almanac, 424978, 425143
   exit
svn add Almanac_2015-03-26.*
svn commit Almanac_2015-03-26.*

There are actually two versions of this file, one that is an ASCII file (with .txt extension) and one that is a FITS file (with .fits extension).

Writing the human logs

THE FOLLOWING NOT YET UPDATED FOR MOSAIC-3

Please write about what happened during your night: weather conditions, which pass you observed, and telescope problems. Follow the example on the pages at DecamLegacy/ObservingLogs.

Catastrophically bad frames (such as saturated frames, or where the telescope moved) are recorded and svn-checked-in to products/mosaic3/logs/bad_expid.txt.

In case of technical difficulties

We have in the past encountered technical difficulties that have restricted where we can observe to a specific range in RA/Dec.

If this happens during your run, you have several options:

1. First, try running mosaicstrategy.py with an appropriate --airmass-limit and/or --moon-sep-limit to try to keep to the required range of tiles.
   
2. Shorten your observing period (using --start-date,--start-time and --end-date,--end-time) such that it's scheduling fewer tiles.
3. Increase the assumed seeing such that it schedules longer exposures.

For reference, the tiles we’d be observing with MOSAIC3 in z-band are:

IN_DESI = 1 DEC > 30 88 < RA < 301 PASS <= 3

That’s 48760 tiles.

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Example run-through for a given night

---

Update everything

Log into the mzls account on the mayall-idl machine.

Update the code, log files and most importantly the tile file:

cd ~/products/mosaic3
svn up
cd ~/products/observing
svn up

Set the paths

The data path must be changed to point to the current night's data. Edit the entry for MOS3_DATA ~/.bashrc file, for example if the start of the night is 13 Dec 2015 change this to

export MOS3_DATA=/mosaic3/data2/observer/20151213

Create nightly plan

Create the nightly plan from the available tiles. This will read the tile file to see which ones are already completed.

cd ~/products/mosaic3/json
python py/mosaicstrategy.py -t obstatus/mosaic-tiles_obstatus.fits -d *UT date at ''start'' of night* -p *portion of night* -pass *pass number*
python ./py/jnox.py --in *JSON input file --out *Output shell script
scp *output shell script to the /home/observer/exec area on mosaic3

Start up mosaic control software

On mayall-2, double click on the MOSAIC3 icon, which brings up the MOSAIC3 Menu on the left edge of the screen.

1. Start the camera control program by pressing the yellow "Start Cameras" button. Wait for this to finish, then dismiss the screen by typing any key as instructed
2. Start the MOSAIC3 NOCS software by pressing the blue "Start MOSAIC" button. This launches a blue xterm. Move it out of the way and watch all the windows come up
3. Rearrange the desktop as needed.

If, for some reason, the buttons do not work, you can start up the software on a command line as follows: On mayall-2 open a terminal window and:

ssh -XY observer@mosaic3
nocs start ccp (this is equivalent to the "Start Cameras" button on the MOSAIC3 Menu)
nocs start all (this is equivalent to the "Start MOSAIC" button on the MOSAIC3 Menu)

Once nocs is up and running, rearrange windows as desired, and check the status of the system by typing the following in a nocs terminal window:

nocs status all
nocs fullstatus ccp

Set the PROP-ID and Project Info

On the NGUI window, press the "Set Project" button and fill out the relevant information. For example,

Principal Investigator: Arjun Dey
PIs Email Address: dey@noao.edu
Actual Observers: Tristram Shandy, Bertram Wooster
Observing Assistant: Karen Butler
OA's Email Address: 4meter@noao.edu
Proposal Identifier: 2016A-0453
Telescope System: KPNO Mayall 4m
Science Instrument: Mosaic 3

Please ensure the Proposal Identifier number is correct''

Then, in one of the NOCS xterm windows, type: "nocs set project"

Take a test image to ensure everything is working

Check that all is well by taking a test zero exposure. On the IRAF window, check the image statistics by cd-ing to the correct directory and typing "mscstat <filename>"

Take dome flats and zeros

During the afternoon (after 4pm), take dome flats with the telescope pointed at the white spot.

1. Check that telescope is pointed to the white spot with mirror cover open
   
2. Take 10 zero exposures
   
3. Turn on low dome flat field lamps at 100% intensity (~50V)
   
4. Create a dome flat script using the NGUI interface. Exposure times as follows:
   

z-band : 20 sec
r-band : 25 sec
g-band : 20 sec

Take 11 flats in z-band every night; only take flats in other bands if you intend to use them. Counts should be ~18-20k adu.

5. Take 20 zero exposures
   
6. Go eat dinner
   

Start the automated script for updating the tile file

From a terminal on the mayall-idl compute, in the mzls account, start this running:

idl
   muptiles

From another terminal in the mzls account, start this running:

idl
   mosstat_continuous

This will run mosstat on each frame as it shows up and display the results on the screen.

Observe - start of night

0. No on-sky observations are permitted before 12 deg twilight.

1. At start of night, check telescope pointing and zero the telescope coordinates using a bright star placed on the telescope boresight (defined as the center of the mosaic3 focal plane).

2. Move to the beginning of the first MzLS tile position

3. Focus the telescope
   

- create a focus script using the NGUI
 - run the focus script from the /home/observer/exec directory 
 - analyze the focus image using mscstarfocus 
    - edit the mscfoc.cl script to correct the name of the image that needs to be analyzed 
    - mark about 10 stars around the image; mark the top star in each sequence using "m"; "q" to quit 
 - log the Truss temperature 
 - set the telescope focus  
 - focus the guiders; this way you can use the guider images to monitor focus drifts

Observe - all night long!

Execute mzls*sh script

In a nocs terminal window (on the mosaic3 computer): Go to /home/observer/exec, and execute the mzls*.sh script.

Monitor focus by checking the image quality on each frame. Keep track of the truss temperature variation and modify the focus as needed. The Mayall has astigmatism, so one can tell from the shape of the images which way to move the focus.

need a figure here

If conditions change compared to assumptions for the script, re-run strategy.

End of night

No on-sky observations are permitted with MOSAIC3 before 10 deg twilight or after 10 deg dawn. No twilight flats are allowed.

At the end of night, shut down the software.

1. Ensure that the "Shutter" and "ready" are both in the "Dark" position on the MCCD gui
2. Press the red "Stop MOSAIC" button on the MOSAIC Menu gui. Wait for this to finish.
3. Then press the yellow "Stop Cameras" button on the MOSAIC Menu gui.

If the buttons do now work, then go to one of the NOCS xterm windows and type:

nocs stop all (equivalent to pressing the "Stop MOSAIC" button)

Once nocs is shut down, type

nocs stop ccp (equivalent to pressing the "Stop Cameras" button)

Once this is done, type

nocs status all nocs fullstatus ccp

and make sure everything is shut down. Only when this is done, is it safe for the OAs to put on the lights in the dome.

Create the Almanac and Almanac plot files

At the end of the night, create the Almanac files and check them into svn.

- cd products/mosaic3/logs
- idl
- almanac,<first exp num>
- plotalmanac,'Almanac_date.fits',ps='plot_Almanac_date'
- exit
- svn add *Almanac_date*
- svn commit

Create a log file

THE FOLLOWING NOT YET UPDATED FOR MOSAIC-3

Generating a Coverage Map

The code pro/coverage_plot.pro will generate coverage maps for a given date range using the info in mosaic-tiles_obstatus.fits. To run it, login as ??@?? and start IDL:

IDL>.com coverage_plot

To produce the plot for a single night use, for example:

IDL> coverage_plot, datemin='2015-04-07', datemax='2015-04-07'

To produce a plot for a range of nights use:

IDL> coverage_plot, datemin='date-start', datemax='date-end'

To produce a plot for all nights to date use:

IDL> coverage_plot

All plots will be put in $??_OBS/obstatus/Plots. The default is to output a PDF but there are flags to output other formats.

The code pro/coverage_plot_alldates.pro will produce a set of cumulative coverage plots (one per day) over a date range. Within IDL when logged in as ??@?? you enter:

IDL> .com coverage_plot_alldates
IDL> coverage_plot_alldates, datemin='date-start', datemax='date-end'

All plots, consecutively numbered, will be put in $??_OBS/obstatus/Plots/PDFs and can be combined into a movie, e.g with the free graphicconverter ​http://www.lemkesoft.de/en/image-editing-slideshow-browser-batch-conversion-metadata-and-more-on-your-mac/ program on Macs.

Ben Weaver would prefer that we do not upload any plots to SVN but rather just the code. So feel free to mail plots around but there is no need to check them in.

Thank the OA and go to bed

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Pages linking to PublicPages/MayallZbandLegacy/NotesforObservers:

• MayallZbandLegacy
• MayallZbandLegacy/NotesforObservers
• MayallZbandLegacy/ObservingSchedule
• MayallZbandLegacy/Run08
• MayallZbandLegacy/Run13
• PublicPages/MayallZbandLegacy
• PublicPages/MayallZbandLegacy/NotesforObservers/Copilot