Surface error: photogrammetry
Measuring the panels with photogrammetry:
Adjusting the panels:
Reflective targets are placed on each panel
Pictures of the dish are taken from the top of
Films are measured on an optical measuring
about 3 months).
Back fit for camera position and determine
each target (no distance scale, only angles).
Survey (using a theodolite) some reflectors to
put a distance
scale on the measurement.
North/south support cables have tieback cables
be adjusted to pull the cable catenary close to the spherical shape.
Each corner of 4 panels can be adjusted
Iterate the measurement and adjustment.