These pages are here to provide engineering information about current status of calibration lamps that are used in the ING. Configuration on the WHT A&G lamps and the Nasmyth calibration box can be found here.

General information

On the WHT telescope there are two places for calibration (comparison) lamps.
1) inside the A&G box for calibrating instruments on at the Cass focus
2) on the outside of the Telescope centre section (broken cass) for calibrating instruments mounted on the top end.

In the calibration box on the centre section of the telescope is space for 4 calibration sources. Light from these sources is directed to the Nasmyth flat and reflected upwards to the top end where the instrument is mounted. In this box is also a spare power supply that can be used when the main power supply fails.

Other power supplies can be found in the WYFFOS Long Camera cabinet underneath the observing floor and in the INT Coude lab in the first grey cabinet on the right.

The types of lamps available are the small Penray lamps and the bigger Hollow Cathode lamps. Most of the Hollow Cathode lamps are quit old and even spares may fail. The Penray lamps are newer and more used in new instruments. For details on the lamps or to order them have a look at the following websites:

Penray lamps http://www.lot-oriel.com/pdf_uk/all/light_spec_cali.pdf http://www.uvp.com Hollow Cathode lamps http://www.hilger-crystals.co.uk/prior/stand.htm http://www.sjjuniper.com/home.asp

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Lamp notes

Calibration lamps for the broken Cass calibration box can be found in the Filter and optics cabinet on the observing floor. The installation of these lamps has to be done by an engineer on a support astronomer. The available lamps for broken Cass with notes are listed here: