PreCam Observers' Guide (Old)

The lava lamp is lit; precam observations have started.

There is a public skype chat called Precam Obs that we are in every night. Ask the observer to be invited in.

Attention PreCam Observers:

Just a reminder that the bearings on the Curtis-Schmidt dome shutter are starting to show their age (see Pat Seitzer's email from Nov. 11)

Pat suggests:

"Please listen carefully when the dome opens and closes. If you hear strange noises, please report them immediately

on the [CTIO] nightly report. You probably will have to turn the fan off to hear anything."

We have a functional telescope:

Optics were a problem! See the optics pages. The removed secondary on the left, the replaced old secondary on the right.

We Hereby Declare That The DES/PreCam Works in Decimal Degrees!

This is not TCS language, probably not tcsclient language, but in all higher levels of abstraction/scripting!

How To Start the Night:

    • Follow the check lists in Curtis-Schmidt Telescope Operations Guide (The Seitzer document). Yes, you. You'll want a window onto precam@ctiozw, and be in the ~/tcs/dfmtcsdes/ directory. And yes, if you don't know the password you are dead in the water; not even SISPI will start without it.

      • idome: this command is less than useful if one has not put the dome at 90 degrees E (the mark on the wall, not compass) where it belongs and where the check list says to put it. The domeflats command won't work, for one: it is likely the idome command tells the TCS that the dome is at 90 degrees E whether it is or not.

    • Once the telescope is functional, move to the PreCam User's Guide (The Sypniewski document: aka, Adam's document).

    • SISPI: keep the PanView debug, the OCS, and the Console windows up, minimize the rest. Keep Labview up.

    • Nightly checklist step 4 is a "to be hoped for", not "this is the current state of affairs"! Right now (Sept 4 2010) we are running warm, and disbelieve the pump gauge.

    • In fact, I query whether the checklist is in the right order- I would start with the telescope, then move to the SISPI/camera things, placing steps 1-8 after step 9.

      • step 8, in fact, is just in the wrong place. One cannot do dome flats before following the Curtis-Schmidt Telescope Operations Guide.

      • section 2.5 (taking images) should go after section 2.2 (starting sispi) and section 2.3 (starting labview) should go before section 2.2 (!)

    • We should add a picture of the dome 90 degree E marker!

  • If the filters were changed before your run, say you are the first observer after a NASA run, then the tip/tilt box was probably power cycled and needs to be re-initialized. The commands are:

    • cd ~/tcs; python tcsclient.py filter init

    • cd ~/tcs; python tcsclient.py focus init

Taking Data:

    • SISPI: in the OCS window, the phrase: "IB is ready for next image" is the key for you to take another image.

      • but if I do it too fast I seem to see "Invalid Transistion- (Current state: Post-Processing input_symbol: Begin Exposure)"

        • which causes SISPI to go into a bad state.

        • restarting SISPI worked.

        • you know, I don't mind typing the "configure" into the OCS on SISPI start, but those 4 "pan set" commands are a bit excessive....

          • It would be nice if the guide mentioned the correct return string for the pan set commands. It is "Done", not, say, "No Reply"

      • I'm having to reboot SISPI about once per hour.

    • Checking the dew point versus pressure to decide on pumping. Why, oh why, is the manual in Centigrade when the temperature gauges in the DES control room read K? It is 5:00am, we're dead tired, and you want to trust my ability to make that conversion?

End of Night Report:

    • CTIO asks for a end of night report. The audience for this is TelOps - think of this as your means of communicating to them problems with the telescope, optics, dome, and instrument. They are, of course, not able to do much with problems with SISPI, QuickReduce, or ObsTac.

  • Don't do what the guide says about end of night data!

      • instead: cd /data1/images; mkdir 2010MMDD; mv fits/P*fits 2010MMDD/;

      • then follow pushdir instructions

      • (there is a file in /data1/images/fits that contains renamed fits files and is crucial for SISPI to function. Don't delete it! Don't accidently move it!)

    • I can understand exiting SISPI at the end of a night, but exiting LABVIEW doesn't make sense to me.

    • delete all the files in /data1/images that match P*fits and P*SENT. The real data live in /data1/images/fits (before you move them, of course). Along those lines, do a df on precam1 once in a while to make sure the /data1 disk doesn't fill up.

Things I Wish:

  • I wish we had a bug reporting system for SISPI errors!

    • We have been using the electronic lab notebook, PreCam, using Steve's account.

  • HOW DO I START QUICK REDUCE?

      • use firefox, at url: ctiozw.ctio.noao.edu:8080

      • go to the Tools tab, select PreCam, and look at results.

      • right now this is just raw images, but once we get the headers more straightened out, we can do bias/flat corrected images. Then, full reductions.

    • Skype public chats work well. The observer opens it, then invites others on their contact list to join. Many chatters at once.

    • Laptop use:

      • So, is it possible to run ds9 on ctiocw and have it display on my laptop?

        • do ssh -X precam@ctiozw

      • Why is it so painful to get data onto my laptop to analyze? I have to give a password every time I scp a frame over...

        • Michael uses sftp, which gives a constantly open session after one password. Nice

        • scp asks for passwords, and its takes forever to ask for a password! In fact, it is intolerable.

          • I always wander away to do something else while waiting for the password prompt and come back after the timeout

        • Adam suggests SSH certificates...

Image things:

    • Bias is ~2000. I wish we could write a table of bias for all four amplifiers.

    • Flat fields should be > 15 seconds to avoid shutter timing map issues. So, aim at ~30,000 counts above bias.

      • g: 15 seconds

      • r: 20 seconds

      • i: 25 seconds

      • z: 15 seconds

      • y: 25 seconds

  • (DLT: These exposure times look good to me. Thanks!)

Pressure, temperature and dew point:

    • The table in the Adam document p17 is in whack units, since everything in the DES control room is in Kelvin. So:

      • For example, if the lowest pressure you are able to pump the dewar down

      • to is 4000µTorr, then the lowest temperature you can set the heater to is

      • 193K (because, from the table, you aren’t allowed to go to 183K until

      • you’ve achieved a vacuum pressure of 1000µTorr).

        • the orange lines are at 3000 microTorr and 9000 microTorr

General Sections:

    • PreCam User's Guide (PDF file)

      • Authors: Adam Sypniewski and Wolfgang Lorenzon

      • This is a guide for operating PreCam. It attempts to cover all of the operations a typical PreCam user/observer would need to consider. You should use this as a guide and reference when observing.

    • Curtis-Schmidt Telescope Operations Guide (PDF file)

      • Author: Pat Seitzer

      • Please send any corrections, suggested modification, or additions to Pat for inclusion in the master copy, which he will keep updated at the above link.

      • We should get a copy of this printed out and kept in a visible place in the DES Control Room. These are checklists to follow.

    • PreCam camera commands (link to a subpage here?)

Failures and Fixes:

    • Where's the lava lamp? Where is the music? bring your own! (....and I heard "In the Flat Fields" on the radio in the La Serana dorm the night before I got here. Just like my thesis days, I say as I work out the exposure times for flat fields.)

User Hints:

The dimmer that controls the lights in the DES control room? The light switch in the anteroom with the stairs turns them on and off.

The large ladder- the temptation is to push it into the corner behind telecope mount. Thats fine, that's where it goes; just be careful that it isn't hitting the preload cable running to the weight hanging from the wall- the thing that looks like a clothesline.

The telescope doesn't point clear of the lower slit for zenith distances greater than 55 degrees.

Miscellaneous:

DES observers may open the two hatches on the tube to inspect the condition of the secondary and camera. In particular, the hatch on the south side allows inspection of the CCD focal plane, shutter, and filter bolt. If there are problems with the shutter or filter bolt, viewing through this hatch allows instant visual checks.

However, under no condition will any DES observer place anything inside the tube - be it hands, flashlights, tools etc.