User's Guide to the Gemini Twin-Arrays Infrared Camera

Table of Contents

Quick Reference
What is Gemini?
Summary Table
Quick start - for the expert
Not so quick start - set-up
Graphical User Interface
More About Gemini
Signal-to-Noise Estimates
Sampling Modes
Writing Scripts
Observing Recipes
Computer Setup
Testing the Arrays
Instrument Maintenance and Trouble-Shooting

Mt. Hamilton Homepage

Quick Start

Assuming the instrument is cold and stable, i.e. 48 hours since start of cooldown, then, at the instrument on the telescope:

Back in the control room:

Check the STARTUP menu and make any corrections necessary, e.g. the DATE, FILENAME PREFIX, STARTING FILE, or any other setting (e.g. filters, dichroic, mode - only necessary if this is an unexpected re-start after a crash), then press the Esc key.

After slewing to a target, do a PC-T Reset (Engineering menu) to prevent noise pickup from the slew motors from disrupting communication between the instrument and the control computer.

Press F1 to enter the "Next Observing Setup" panel (black background) for channel A and set the Object name, Integration time (Itime), Co-adds, Filter and clocking or Sample Mode (SampMode) scheme - usually mode 1 (Single Sampling) or mode 2 (CDS) for tests. Press Esc when done. Repeat for Channel B (using the F2 key).

Press F4 for "Go2" which starts and exposure in both channels together. The resulting images will be displayed automatically (with statistics), the frames will be saved, and the filename will be updated automatically. Alternatively, press Ctrl F4 to achieve the same effect as above, but the data will not be saved and named as part of the normal filename sequence.

While an integration is in progress you can re-enter the "Next Observing Setup" panel and set up a new sequence. Since control is returned to the PC after the integration begins, the PC can also be used to process data already saved on disk. By selecting "TV" from the Menu Bar you can also switch control to the Display Monitor and use the (redefined) function keys to get pixel values, line plots and aperture photometry.

At the end of each night:

The LN2 needs to be filled at the end of each night's observing. In addition, it is very important to TURN OFF THE MOTOR DRIVERS at the end of each night; a power outage during the day could cause them to be powered on, implying excess heat within the dewar.

Last modified: Mon Dec 23 11:56:42 PST 2013 by Elinor Gates