band_pass_filters: Indexing of filters of different curve types
Description
Vectors of names of member objects grouped according to their type or optical
properties. Band-pass filters transmit a range of wavelengths, but block
shorter and longer ones. Long-pass filters absorb wavelengths shorter than
their cut-off and short-pass filters absorb wavelengths longer than their
cut-off. Multi-band and single-band pass filters are listed together.