Photogrammetry Workshop Session 1: Fieldwork Exercise Chris Leung RIBA photogr

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Photogrammetry WorkshopSession 1 Fieldwork
ExerciseChris Leung RIBAphotogrãmmétry n.
Process of making surveysor geodetic
measurements by photography.Bartlett
Diploma Unit 23Thursday 14th December
2006Location Ham Yard London W1
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• ObjectiveTo produce a three-dimensional digital
  model of the site using digital images and the
  technique of photogrammetry.
• Sequence of Work
• Understand how to photograph a subject with
  images that can be used effectively by the
  photogrammetry software.
• Working with the photogrammetry software to build
  a geometry solution.
• Scaling, Orientation and export of the geometry
  to a CAD package.

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• Decide the subject that will be modelled.

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• Take the photographs of the subject from
  different angles but keep the points of interest
  visible in as many images as possible. The more
  points that are visible, the more there will be
  to model later.

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• When you cannot photograph a subject from all
  angles, aim to photograph an overlap between sets
  of images.
• More images are better too few.

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• Keep the camera set to the fixed maximum
  wide-angle FOV (field-of-view) at all times.

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• ScaleChose two points of interest that were
  identified earlier and measure the distance
  between them. The further apart the points the
  higher the probability of a more accurate scaling.

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• OrientationChose a line between two points that
  lies in the horizontal plane and use a compass to
  record the bearing from the north of that line.