Previous: Introduction
Up: Filters for use with the CCD cameras on La Palma
Next: Kitt Peak Interference Filters (BVRI)
Previous Page: Introduction
Next Page: Kitt Peak Interference Filters (BVRI)

Mounting CCD filters

The filter cut-out is designed to take 2.0 inch square filters (in a 51 mm square hole); a 47 mm clear aperture is provided.

In addition, filters up to 56 mm diameter can be accommodated, although in this case light can "leak" around four corners unless a mask is fitted.

Any smaller filters should be mounted within a 2.0 inch square frame which is then readily fitted to the wheel.

The maximum thickness of filter allowed is 12 mm ; filters of thickness 3 mm will require packing material to stop them moving about within the 3 mm deep cut-out hole; filters of thickness 3 - 12 mm can be held in place with adjustable clamps.

All filters of a set should preferably be of the same optical thickness to minimise focus changes. Relevant fous shifts for all of the filters in this note will be given in the INT and JKT CCD manuals (currently in preparation).

Kitt Peak Broad Band Interference Filters

Glass Broad Band Filters

Emission Line Interference Filters

H alpha redshift Interference filters

Value to be entered into the WHEEL command (See Section III.5.4)

In units of focus encoder relative to a 3mm filter

Two filters available

Only 25mm square

Table 1 List of currently available filters for CCD cameras on La Palma