Stereo Analyst Extension

• ERDAS product

• Extension for ArcGIS Desktop

• View stereo image pairs

• 3D feature collection

Stereo Analyst Extension

• Project Geology request– Historic aerial photography of Sisk Dam

construction site

– Looking for explanation of structure feature underneath dam

• Aerial photography archive– Retrieved film with 60% forward overlap

– Scanned to digital format

Stereo Analyst Extension

Stereo Analyst Extension

Stereo Analyst Extension

• Image files must be “oriented” but not orthorectified– Process done in a photogrammetric software

application, e.g. LPS, Socet Set, ImageStation

• Extension used to:– Collect features in 3D for better horizontal

accuracy

– Collect mass points for creating elevation models

Stereo Analyst Extension

Stereo Analyst Extension

Stereo Analyst Extension

• ERDAS pricing– License ±<$4,000

– Maintenance ±<$800 annually

• Stereo accessories– Was ± $3,600 per unit

– Now ± $600 per unit

• High end graphics card– ± $4,000