A professional who identifies and verifies information shown on aerial photographs used in map making. Responsibilities include:

• Travels over photographed area to observe and record all cultural and drainage features shown and not shown on photograph.
• Verifies numbers, names, and classes of roads and highways, location and number of railroads, location of state and county lines, and location and identification of streams, rivers, lakes, schools, and major buildings.
• Marks observations on map overlay, using specified symbols.
• Determines elevation of hills, trees, and buildings, using geometry.
• Obtains boundary and other official information from county records.
• May use stereoscope to combine information from two aerial maps.