Photographs may be either landscape scale, or photographs of ground cover associated with transect lines.
1. Take the photo from the same point, in the same
direction, each time the photo is repeated. It is often useful to take a
copy of the photo to be repeated to the field with you to compare the archive
photo with the view in your viewfinder
2. Use a date back camera, which documents the date
the photo is taken on the face of the photo. Avoid using different focal
lengths, etc in repeating a photo
3. Try to take the photos on or about the same time of year.
4. Document and save with the photograph the objective for initiating a set of photographs and whatever information would be important in making inferences regarding trend. Placing a clipboard with appropriate information in the photo can be invaluable in keeping photographic records.
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