Jawaharlal Nehru Technological University Hyderabad B.Tech IV REMOTE SENSING AND GIS Previous Question Paper (July/August - 2022 - R16)

Aerial photography is the process of taking photographs of the Earth's surface from an elevated position, typically using cameras mounted on aircraft, drones, or balloons. It provides a bird's-eye view that captures spatial relationships and features that are often difficult to discern from ground level.

Key applications include:

• Topographic Mapping: Creating accurate base maps and digital elevation models for land surveying.
• Urban Planning: Monitoring urban growth, infrastructure development, and land-use patterns.
• Agriculture: Assessing crop health, monitoring irrigation systems, and estimating yields through multispectral imaging.
• Environmental Monitoring: Tracking deforestation, coastal erosion, and changes in natural habitats over time.
• Disaster Management: Rapid assessment of damage following floods, earthquakes, or wildfires to coordinate emergency response.

Stereoscopy is the technique of creating or enhancing the illusion of depth in an image by presenting two slightly different perspectives of the same scene to the left and right eyes. By overlapping two aerial photographs taken from different camera positions (stereopairs), the human brain perceives a three-dimensional model of the terrain, known as a stereomodel.

Different types of stereoscopes include:

• Pocket Stereoscope: A small, portable device consisting of two simple magnifying lenses. It is ideal for field use but covers only a small portion of the stereopair at a time.
• Mirror Stereoscope: Uses a system of mirrors and prisms to reflect the images into the viewer's eyes. It allows the entire stereopair to be viewed simultaneously and provides more space for annotating or measuring the images.
• Scanning Stereoscope: An advanced version of the mirror stereoscope that includes a scanning mechanism, allowing the user to view large-format photographs without moving the prints.
• Zoom Stereoscope: Incorporates a zoom lens system, enabling the user to vary the magnification of the imagery to examine fine details in the stereomodel.