The Raymond and Beverly Sackler Magellan Instant Camera


New Manuals (2010 Aug 04)!

Table of Contents


0. MagIC Current Status

MagIC Location

Folded Port of the CLAY 6.5-m telescope.
Available for scheduled (full-night and shared-night) use.

Availabe Camera Operating Modes

Quad, dual and single-amp readouts.

Binning 4x4, 2x2 or 1x2.

Readout time: ~20 seconds (quad amp 1x1).

Output file contains serial and parallel overscans for each quadrant for bias calibration.

Filter Status

Filters installed:
Johnson-Cousins: B, V, R, I
Sloan: u', g', r', i', z'
Custom: VR

Filter positions recorded in lookup table.

Folded Port Guider Status


MagIC is permanently mounted on one of the three folded ports, allowing the rapid switching between MagIC and other scheduled instruments.



1. Introduction

MagIC (the Magellan Instant Camera) is a high throughput CCD camera system built as the first facility instrument for the Walter Baade telescope, one of the two Magellan telescopes. Personnel from the MIT departments of Earth, Atmospheric and Planetary Sciences and Physics and from the MIT Kavli Institute for Astrophysics and Space Research and the Harvard-Smithsonian Center for Astrophysics contributed to its construction. MagIC consists of four components; i) an instrument rotator, ii) a dual-probe guider/wavefront sensor, iii) a filter wheel and shutter mechanism, and iv) a high quantum efficiency, wide spectral coverage, cryo-cooled, back-illuminated, thinned CCD camera and associated electronics. The camera is run from a single science workstation via a custom software package (LOIS) developed in collaboration with colleagues at Lowell Observatory. The instrument was initially deployed at the Baade telescope in March of 2001 and has undergone several upgrades and refinements since then. MagIC is currently mounted at a folded port of the Clay telescope, always ready for observations and rapidly accessible by rotation of the tertiary mirror. The combination of optimized scheduling and a highly efficient, instantly accessible camera allow the Magellan partners to pursue science programs not possible or practical elsewhere. MagIC was conceived to tackle such programs as optical follow-up of gamma ray burst sources, monitoring of the light from gravitationally lensed quasars, occultations of stars by solar system bodies, high precision photometry of microlensing events in the Magellanic Clouds, physical studies of recently discovered near-earth asteroids, optical follow-up of supernovae in distant galaxies, and exploration of the Kuiper Belt.

1.1 Design Goals

1.2 MagIC Technical Characteristics

The current MagIC focal plane houses a grade 0 SITe 2048 x 2048 pixel CCD array. The MagIC dewar is always kept cold, cooled by a closed cycle CryoTiger to a detector temperature of –120 C.


SITe SI424a Specifications
Detector Size 2048 pixels x 2048 pixels
Pixel Size 24 microns
Focal Plane Scale 2.89 arcsec/mm = 0.069arcsec /pixel
Field Of View 2.35 arcmin x 2.35 arcmin
Quantum Efficiency 85%-400nm; 82%-700nm; 48%-900nm (SITe lab measurements)
Output 4 output device @ 50 +Kpix/sec
Readout 4 amp, full frame = 20 sec


2. Performance

2.1 Gain, Read Noise, Saturation, and Linearity*

Camera Mode: Unbinned, 4-amp readout
Gain (e-/DN)
Read Noise (e-)
Saturation Level (ADU)
A/aka 1
linear to saturation
B/aka 2
linear to saturation
D/aka 3
linear to saturation
C/aka 4
linear to saturation

* Results from June 2001 Engineering data at the Baade

Amplifier C/aka 4
Amplifier D/aka 3
Amplifier A/aka 1
Amplifier B/#2


2.2 Throughput*

Transmission Curve
Absorption Curve
mag for 1 e-/sec
extinction coefficient

* Results from June 2001 and March 2004 Engineering data.

**custom filter for KBO observations, see Jewitt, D., Luu J., & Chen J. 1996 Astron. J., 112, 1225.

Filter Slide Drawings — View1.PDF, View2.PDF or View1.PS, View2.PS

3. Observing

3.0 The LOIS data acquisition systems

LOIS, the Lowell Observatory Instrument System, is versatile data acquisition software used with optical and infrared detectors. MagIC was initially installed with version 1 of LOIS, but was upgraded to version 4 in August 2006. Version 4 runs on a the computer named "magic2." Version 1 runs on a the computer named "magic1," and serves as a backup system in the event of difficulties.

3.1 MagIC/LOIS User Manuals

3.2 Star Charts

If you need a star chart, note that a five-second exposure through the Sloan r' filter goes to about the same depth (at full moon) as the Digital Sky Survey. To download a DSS chart, go to the web site Select the second generation red survey and an appropriate size to use is 3' x 3', which is a bit larger than MagIC's full frame field of view.

3.3 Things to Watch Out For

  • The MagIC Blog
  • The most recent topics of discussion concerning MagIC can be found on the news and forums webpage

  • Dual Filter Wheels
  • Each filter wheel is set independently, so do not forget to have one of the wheels set to the open position. If not, you will be exposing through two filters at once! Both filter names will be written in the FITS header.

    In version 1 scripts could not (and still can not) be aborted or interrupted short of quiting the running LOIS session. This represented a major shortcoming. In version 4 scripts can be aborted when the camera is exposing or reading, but NOT when the filter wheel or telescope is moving.

  • Phantom Pixels
  • When operated in single amp mode (available only in version 4) two phantom pixels are inserted at raw row number 1991. The last 4 arcseconds of data are therefore shifted by 2 pixels. All of the data are present and can be recovered, but many users may just choose to ignore the last 4 arcseconds.


    Appendix A. MagIC Analysis Scripts and Reference Material


    Appendix B. Magellan I Schedule


    Appendix C: Responsible Individuals

    Point of Contact at MIT: Jim Elliot

    Point of Contact at LCO: David Osip


    "MagICians" can be contacted through our mailing list:

    Any problems should be documented and sent to the mailing list.