The article I read titled "Photogrammetric monitoring of small streams under a riparian forest canopy" had a lot of interesting information regarding their approach to studying stream outlines in a similar manner that we are. The study showed that high resolution digital elevation models can be created from close range stereo imagery of pictures taken 10m above the stream with a unipod. As we suspected, they did post-processing to eliminate perspective and other distortions of the picture images. The platform utilized minimized perspective distortion which, as we have seen through our struggles with Hugin, is a very appealing option.
Specifically, this study used Leica Photogrammetry Suite 9.2 and ERDAS Stereoanalyst to obtain 3D and/or stereroimagery of the stream.
Two parts of the study that especially caught my attention were the use of additional ground control points for vertical and horizontal lines and the suggestion to take pictures on an overcast day to eliminate reflections of the water.
Overall, I think the best part about this paper is the vast number of sources used that we can further explore to enhance our understanding of the struggles and triumphs of as many different procedures as possible.
The unipod is a very cool idea and you did find a gem of a paper!
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