Using observations of data acquired through a tunable, liquid-crystal filter of the central region of the Jewel Box cluster, NGC4755, a tunable, liquid-crystal filter was tested to see how well low-resolution spectrophotometry of multiple stars within a moderately crowded field could be performed. To evaluate the filter, the filter’s central wavelength was stepped from 435 nanometers (nm) to 720 nm in successive intervals of 5 nm. Given the limited telescope time, the flatfield data obtained was stepped in intervals of 50 nm. Zoran Ninkov, Robert Slawson and Elliott Horch, the three RIT faculty/staff members working in the project, assumed that it would be possible to adequately correct the data for spatial transmission using such widely spaced flatfield images. After reviewing this data, it was found that this belief was in error. The mission of this Senior Research Project therefore was: Examine the magnitude of the flatfielding errors in different regions of the data field; Test whether or not data corrected with flatfield images obtained in the laboratory rather than at the telescope improved the data analysis; To see how well the spectral extracted for a few stars in the cluster, with known spectral type agreed with the expected spectra from a standard atlas (i.e. Gunn & Stryker).
Hoheusle, Katherine, "Astronomical hyperspectral imaging flatfield corrections" (2000). Thesis. Rochester Institute of Technology. Accessed from
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