LIRB Pages
Home
LIRB NAWQA
Basin Information
Ground Water
Surface Water
Bed Sediment & Fish
   Tissue
Ecology
Maps
Illustrations
Survey Data
Aerial Photography
    R/C Helicopter
    Camera & Film
    Camera Rig & Struts
    Photographs
Publications
Staff
Data Retrieval

 Parent Pages
USGS Home
NAWQA Home
Illinois Water Science Center Home

The still camera mounted to the helicopter is a Canon EOS Rebel G with a 28 millimeter lens. The camera is set next to manual focus and the lens adjusted to infinity. This is done so that the camera does not adjust focus from the ground to the tree tops or to any other "interference" with the ground. Although the wide angle lens introduces more distortion of the image along the photos edges, the same lens provides a larger area of coverage. This increased coverage area is important because it increases the probability of photographing three or more of the ground targets in each frame of the film. Having three or more ground targets in each photo makes it possible to rectify the photos.

Film speeds of 100, 200, 400, 600 and 800 were tested from the helicopter under like conditions. The 400, 600, and 800 speed films showed little difference in the sharpness of the photos. Because of its availability in stores, 400 speeds film is used for the aerial photography. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.