ABSTRACT

One factor to keep in mind is that the smaller the area covered, the higher the cost per unit area. Airphotos or airborne imagery will almost always cost more per unit area than satellite images.

2. Timing If the imagery is needed immediately, one can screen grab free but rather low-

quality imagery from internet sources such as Google Earth (subject to their License Agreement) or purchase off-the-shelf data from a government agency or vendor. Large image archives exist, and data can often be obtained quickly. The cost will increase if a “rush” job is requested. Purchasing custom images from vendors and consultants, or processing digital data in your own shop can take up to several weeks.