Figure 4 (a) A power spectrum of raw speckle data from the binary system SAO 100443, showing the characteristic fringes of a binary system, but low SNR at the high spatial frequencies. Contours begin at twice the RMS noise and continue at that interval.
(b) The recovered autocorrelation function of this system (Fourier transform of the recovered power spectrum). Contours at logarithmic intervals: +/- 1, 2, 4, 8, 16, 32, 64, and 99% of the maximum.