HoLiCam - a 2kx2k CCD camera system for the 1m Cass at Hoher List
HoLiCam is the latest of our BOCCIA
Systems. It is the standard instrumentation and the working horse at the 1m
telescope at Hoher List. It can be used with different optical configurations,
CCD detector systems, Filters and
Grisms. Camera control is through a Windows-PC, data
acquisition is to a Linux workstation (IRAF, MIDAS installed).
- In the Cassegrain focus for high pixel resolution imaging.
- In combination with a focal reducer for wide field imaging (parameters
are given below). Due to the overall length of the instrument the declination
range is limited (< 70 deg) in this mode.
HoLiCam optical Configurations
||field of view
||Decl < 70deg
Both setups share the identical filter/shutter unit. It was designed and
build at the Hoher List workshop for this purpose and is used in front of
the CCD dewar (cassegrain setup) as well as in the collimated beam section
of the focal reducer. The shutter is an iris type.
Two systems are available,
both with the same CCD type:
- HoLiCam : 2-sided read out
- HoLiCam "blue": 1-sided read out. The CCD has a UV-sensitve coating
for enhanced UV-response.
- frontside 2048x2048 15micron pixel FA2048.
- liquid nitrogen cooled
- read out noise: 8-9 e-
- "Gain": typical 2.5 e-/ADU
- full well: 150000 e-
- read out time: ca. 70sec 2-sided read out, 140sec 1-sided read out
- binning: 2x2, 4x4 (recommended only for quick checks)
- centered windows of smaller size can be read out
Currently available filters are:
- Johnson B,V,R,I (see filter recipes)
- Halpha Filter: 657.5+-2nm, peak transmission: 80%
With the focal reducer two grisms can be used with different resolutions:
- Grism S300: ca. 2.5 A/Pixel
- Grism S600: ca. 1.3 A/Pixel
The instrument control - including setting of filters and foci - and data
acquisition are fully integrated in the BOCCIA control program running on
a PC in the observers room. The PC is connected to the Hoher List Local Area
Network (Ethernet). Through this connection images are transferred to a Linux
workstation (becker - in the observers room) and stored in FITS format immediately
after completion of each CCD read out. Each new image file may be copied
automatically to DAT tape and/or stored later on CD-ROM.. IRAF is installed
for quick look and full data reduction.
Last Update: Feb. 3, 2003
Klaus Reif (E-mail: email@example.com)