575 
Figure 5. (a) Power spectrum of figure 4(a) the FLI spatial image, (b) Power spectrum of figure 4(b) the FLI spectral image. 
(c) Power spectrum of figure 1(b) the CASI full frame CCD image, (d) FLI spatial image in 5(a) apodized using 
circular, 5% of width, Gaussian shaped, apodization window, (e) Same apodization performed on the FLI spectral 
image in 5(b). (f) Same apodization performed on the CASI full frame image in figure 1(b). (g) Power spectrum of 
5(d). (h) Power spectrum of 5(e). (i) Power spectrum of 5(f). Note that all images except the CASI tree in figure 
1(c) are 256 pixels x 256 lines. This size was used so that all the FFTs could be done without padding with zeros to a 
power of 2. All FFT power spectra are shown with the origin (zero frequency DC component) at the centre and have 
a range of frequencies from 1/256 to 1/2 cycles/element and are diagonally symmetric about the origin.