Photogrammetry: Image Formation and Distortion Analysis

Posted on Jan 28, 2025 in Physics

Maintaining Adequate Air Coatings

In order to maintain adequate air coatings, which of the following statements are correct?

  • With flying height constant, the value of the photogrammetric base increases in proportion to the altitude of the relief.
  • Holding the value of the photogrammetric base constant, the flight height increases in proportion to the height of relief.
  • Keeping the flying height constant, the value between flight lines decreases in proportion to the altitude of the terrain.
  • Keeping the distance between lines of constant flight, the altitude of the aircraft decreases in proportion to the altitude of the terrain.

Image Movement, Optical Distortions, and Earth’s Curvature

What is the relationship between image movement due to optical distortions and displacements due to the roundness and curvature of the Earth?

  • All are radial distortion, but the displacement is greater due to optical distortions.
  • The displacement due to refraction and sphericity are outwards from the center of the photograph, while the displacement due to optical distortions is inward.
  • Atmospheric refraction and optical distortions move the image away from the fiducial center of the photograph, while the Earth’s curvature moves the image towards the fiducial center of the photograph.

Artificial Stereoscopic Vision Methods

Name three methods of artificial stereoscopic vision by converging axes:

Anaglyph, polarized filters, and synchronized shutters.

Components of Image Acquisition and Restoration

Relate the different components of acquisition and restoration of images and identify:

Views, frames, perspective rays, beam intersection perspective, and model.

Image Shift and Camera Calibration

Select the correct answers:

  • The image shift due to forward motion of the plane is directly proportional to the time of opening the shutter of the camera.
  • The certificate of an aerial camera calibration provides us with the information needed to correct the geometric distortions of the image generated by the objective. Thus, we get an image free of distortions resulting radial and tangential.
  • The ripple of the focal plane produces a longitudinal displacement of the resulting image.
  • The value of radial displacement of the image due to the spherical Earth is of equal value to the posting of the image due to atmospheric refraction, but opposite direction.

Cone’s Goal and Image Motion

Select the correct answers:

  • The goal of the cone is to ensure the stability of the focal plane of the camera.
  • The image motion during the movement of the plane is more pronounced in fast films.
  • The variations in the printing of the fiducial marks may not match the image fiducial center.

Interpolated Pixel and Scanner Resolution

Select the correct answers:

  • The interpolated pixel is intended to increase the visual quality of the product.
  • The pixel size of the scanner in the scan direction does not depend on scanning speed, only depends on the characteristics of the pixel sensor.
  • The radiometric resolution of the scanner depends directly on the incident luminous flux.
  • One of the most significant differences between photogrammetric scanners and those used in graphic arts is its dynamic range.

Image Distortion and Geometric Position

Image distortion does not affect the geometric position of a point in the image.

False.