ha16 H-alpha+16nm k1013

Below is a plot of the transmission of this filter when used at telescopes with differing focal ratios and central obscurations; the KPNO 4m (f/3.1), the CTIO 4m (f/2.9), and the WIYN 0.9m (f/7.9). At the KPNO 4m f/3.1 the properties of this filter are: CWL=6705A, FWHM=81A, PEAK TRANSMISSION=91.7%.