BUSCA: a telescope instrumentation for simultaneous imaging in four optical bands

摘要: The 'Bonn University Simultaneous CAmera (BUSCA) is a CCD camera system which allows simultaneous direct imaging of the same sky area in four colors. optics are designed for an f/8 gem and 4K X CCDs with 15(mu) pixels covering field view 12 arcmin at 2m class telescope. In September 1998 BUSCA has seen 'First Light'. instrument based on three dichroic beam splitters separate optical wavelength bands such that standard astronomical intermediate-band filter systems can be used. dichroics made plane-parallel glass plates mounted angle 45 degrees. Astigmatism transmitted beams completely canceled by identical plane- parallel suitable orientation. offers new perspectives multicolor photometry: i) broadband spectral properties objects determined high reliability even non-photometric atmospheric conditions. ii) Precious observing time used very efficiently. iii) With large view, extended like globular open star clusters or galaxies covered single exposure. iv) Each exposure results complete data set.