I am currently working with a client who has a large collection of current and old aerial photography. We are currently indexing and organising this collection. Although many users are primarily interested in the most current imagery available, there are some important uses for old imagery, and in particular being able to compare what is visible in old orthos compared to the situation in more modern orthos. I am interested in good ways to present this data so that it is easy to compare different orthos.
I have managed projects to implement 'side by side' viewers (mainly of vector data) as in the example here: http://gisviewer.hcc.govt.nz/Templates/PropQueryCompare/ .
The useful function with this is that you can pan/zoom etc to different areas and both views continue to mirror the geographic extents but with different data being looked at. I am particularly interested in how people have organised the orthos to support a viewer in this type of configuration.
What I am interested in is whether anyone has done something similar, but with the ability to change each of the windows to different orthophotos of different ages? I think that this could be a good way of presenting the historic imagery that we are currently working with.
Any suggestions/examples please? (hyperlinks to publicly available sites would be great)
