Types of stereoscope

Type of stereoscope

1. Types of Stereoscope & Ground Control Point (GCP) (Aerial Photogrammetry ) Presentation on Presented by Mr .Amol V. Ghogare Assistant Professor, Civil Engineering Dept. SRES, SCOE, Kopargaon .

2. Stereoscopy The use of binocular vision to achieve 3-dimensional effects. Enables you to view an object from 2 different camera positions to obtain a 3-dimensional view . Stereo pairs of photographs Two adjacent, overlapping photographs in the same flight line. Stereo views can only be seen in the overlapping portion of the photos.

3. Stereoscope The binocular optical instrument that help to view two properly oriented photos to obtain a 3- dimensional model Stereoscopic Fusion Stereoscopic fusion is the fusion of two separate images of an object in the brain together with a spatial impression, is called as Stereoscopic Fusion Types of Stereoscope:- Lense Stereoscope Mirror Stereoscope Scanning Stereoscope Zoom Stereoscope

4. Types of Stereoscopes Lens (pocket) stereoscope Simplest Least expensive Small 2-4 x magnification Used in the field

5. Types of Stereoscopes: [A] Mirror stereoscope Photos can be placed separately for viewing Used in the field? Consist of four mirror makes an angle 45 deg with plane of photo Two larger Wing mirror, two eyepiece mirror

6. Scanning mirror stereoscope A series of lenses and prisms Relatively expensive Not used in the field

7. Zoom transfer stereoscope Variable magnification: 2.5 - 20 x Very Expensive Not used in the field Used to transfer features from a stereo-pair of photos onto a map or other photo

8. Stereo Photograph Geometry Orientation of Stereo Pairs 1. Obtain 2 photographs consecutively marked on a flight line. 2. Locate and mark the Principal Points on each photograph. 3. Locate and mark the Conjugate Principal Points on each photograph . 4. Line up all 4 points and adjust the distance between photographs to suit your needs.

9. Ground Control Points (GCP) A ground control point (GCP) is feature that you can clearly identify in the raw image for which you have a known ground coordinate. Ground coordinates can come from a variety of sources such as the Global Positioning System (GPS), ground surveys, geocoded images, vectors, geographic information systems (GIS), topographic maps, extend the number of GCPs in your images. A GCP determines the relationship between the raw image and the ground by associating the pixel (P) and line (L) image coordinates to the x, y, and z coordinates on the ground.

10. The GCP in nature determines the position of its aerial photo image in the coordinate system. To calculate the coordinates for each point on the aerial photography, several ground control points’ coordinates are used

11. Thank you