OMEGA 2000

Omega2000 is an imager in the near-infrared range (from z to K bands), placed on a 3.5-m telescope frontring. Thanks to a carefully designed dewar and baffling, Ω2000 can thus observe with a reduced (thermal) background from 0.85 μm up to 2,5 μm. Its rigid design at the prime focus suffers little mechanical deformations (1, 2 and 3).

Its optics, including a field corrector reducing the f-number to f/2.35, is designed to provide very low distorsion (less than one pixel, center to corner, see also spot diagram) and stable PSF, ideal for accurate astrometric studies (e.g., parallaxes of nearby brown dwarfs). With a single HAWAII-2 HgCdTe detector, Ω2000 covers a field of view of 15.5'x15.4'. The relatively wide field of view and high-transmission optics also make Omega2000 useful for deep surveys, like the ALHAMBRA NIR images of cosmological fields.

Available at: Primary focus of the CAHA Zeiss 3.5-m telescope

Contact: This email address is being protected from spambots. You need JavaScript enabled to view it.

                                                   In a nutshell                                                   o2kPFpos

Ω2000/3.5 prime focus
Field optics
4-lens (f/3.9 → f/2.35)

HAWAII-2 HgCdTe 2048x2048 pixels

Field of view 15.4'x15.4'
Pixel scale 0"45 / pixel
Geometric distorsion <0.06% (<1 pixel)
Wavelength range 0.8 μm to 2,5 μm with high QE
Filter wheels 3 wheels of 7 filters each
29 in total, see full list


 Observing with Ω2000

Preparing observations During observations
After observing
Requesting observing time

Graphical User Interface (GUI).

Macros works, too!

Basic data reduction: Sect. 14 of manual

Original webpage

Troubleshooting Pipeline development: see René Fassbender's dipl. thesis
Full manual Log sheets Alhambra final data release
Exp. time calculator   

Interact with images using MIDAS commands, e.g. o2k/seeing for quick seeing estimate

Detector QE (table)

29 filters7x3 wheels

Note: considering the short exposure times in the NIR (typically 2 to 60 s), NO guiding is required for Ω2000!  


More information


Technical papers: SPIE proceedings (2000, 2002 and 2004)

Diploma thesis of Anke Kitzing and René Fassbender

PhD thesis of Zoltán Kovács


Nice images

Spectacular images taken with Omega2000, at times in combination with other CAHA faciilities (see Vicent Peris website).

Includes the M57 NASA Astronomical Picture of the day, See also Descubre Fondación web page dedicated to M57.


Picture gallery

Includes commissioning, first light, and instrument development images.

Calar Alto Press Releases


New light on the Trifid Nebula, a star nursery as old as Homo Sapiens

A triple quasar discovered

The massive cluster in front of the Orion Nebula

New spectacular signs of star formation in Cygnus

The best proto-brown dwarf candidate so far

Impact on Jupiter image

The oldest brown dwarf

Calar Alto: the darkness in the infrared

A blast from the past

The Pleiades' lesser sisters

The dark also shines

Spacecraft impact on the Moon observed from Calar Alto