Technical photography is the process of recording the precise position of a camera and fixed points in a view using precision surveying equipment. Camera equipment includes full frame sensor Canon 5D Mark III with 50mm lens, Manfrotto panoramic tripod head and precision levelling equipment. Spectra Precision GNSS (enabled with RTK) survey equipment is used for verifying precise camera location.
The technique allows the precise camera position to be correctly transferred to the 3D modelling software to ensure the same camera settings are used. A clear understanding of camera geometry and the scaling requirements of the 3D model renders ensures highly accurate scaled visualisations can be produced, giving clients the comfort of a transparent methodology in accordance with the latest technical guidelines, which has regularly been cross examined at Public Inquiries.
MS Environmental produce both planar and cylindrical photographs and visualisations. These two different approaches have developed as a result of work undertaken by Scottish Natural Heritage, The Highland Council and The Landscape Institute. The Highland Council favours the single frame planar approach whilst SNH favours the cylindrical approach, with re-projection of wider panoramas back to planar.
This photograph sequence from Edinburgh Castle illustrate the differences between these techniques.
Single frame images rarely fully allow proposed developments to be illustrated, particularly in close views. Multi-frame panoramas can be constructed using geometrically calibrated overlapping frames to provide up to 360° views where cumulative effects or landscape context are required. The correct use of a panoramic head, nodal point calculation and cylindrical correction avoids the problems of parallax.
It is important to remember that the cylindrical image should not be viewed on a flat computer monitor, but is designed to be printed, held in an arc at a specific distance and viewed with one eye closed. The idea is that all points on the photograph are the same distance from the eye.