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Next: Image Segmentation Up: Chapter 4 Previous: Introduction


Data Analysis

The dataset used for this study consisted of a 150-minute sequence of 100" x 100" Ca II K3 (bandpass FWHM 0.3Å) images centred on quiet Sun (Solar_X = -25, Solar_Y = -35) at a 45 s cadence. The sequence was part of the dataset described in Chapter 3 taken at the DST (Sacramento Peak / National Solar Observatory), on 1998 September 22 under excellent seeing conditions. Co-alignment of the images with co-spatial and co-temporal TRACE data led to a calculated spatial size for the Ca II K3 images of 0.33 per pixel. All images were initially flat fielded and dark-current subtracted. Each image was then aligned to a sub-pixel accuracy to the first image in the series by means of cross-correlation.



Subsections

James McAteer 2004-01-14