NATL's tracts of upland pine. Gridpoints from which photos were made are ringed with red. |
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Methods: During the early occasions of making photographs in four directions from gridpoints, significant changes in the field of view occurred because of changes in cameras and lens:
Date
Camera
Lens
Field of view
January 1997
Single lens reflex (film)
50mm
medium wide
April 2004
Canon Powershot (digital)
??
wide
Jan to Mar 2007
Canon EOS 20D (digital)
50mm
narrow
July 2009 and later
Canon EOS 20D (digital)
35mm
medium
Other aspects of the methods have remained as those described in detail elsewhere.