The second data set consisted of still images collected at marked
index sites. For each site, overlapping geographically referenced
images were stitched together into tiled-image mosaics using
Autopano Giga 3.0.8 (Kolor) with a combination of automatic and
manual selection of control points for pattern recognition. Mosaics
were sometimes considerably distorted by small differences in
camera angle, target direction, and sponge growth patterns. The
quality of mosaics representation of index sites was assessed
visually by watching corresponding video; the degree of image
distortion was assessed by measuring objects of known size and
shape (e.g., cable and trawl float markers) in source image and in