4.6 Wide Field and Planetary Camera 2 (WFPC2)

The WFPC2 has three "wide-field" CCDs, and one high-resolution (or "planetary") CCD. Each CCD covers 800 x 800 pixels and is sensitive from 1150 to 11,000 Å. All four CCDs are exposed simultaneously, with the target of interest being placed as desired within the FOV.

The three Wide Field Camera (WFC) CCDs are arranged in an "L"-shaped FOV whose long side projects to 2.5', with a projected pixel size of 0.10". The Planetary Camera (PC) CCD has a FOV of 35" x 35", and a projected pixel size of 0.0455". The WFC configuration provides the larger FOV, but undersamples the cores of stellar images; the PC configuration samples the images better, but has the smaller FOV.

A total of 48 different filters may be inserted into the optical path. Polarimetry may be performed by placing a polarizer into the beam, and rotating the filter wheel to one of 4 different position angles. There are a total of 18 narrow-band and medium-band filters, as well as 2 narrow-band quad filters that each yield 4 different central wavelengths on the 4 detectors. There are also 4 linear ramp filters that effectively allow you to image a ~10" region in an arbitrary 1.3% bandpass at any wavelength between 3700 and 9800Å, by means of a variety of filter wheel orientations and target placements within the FOV.