GPS for Dummies.pdf - Engineering Surveyor

Chapter 14: From the Air with USAPhotoMaps2371. From the File menu, choose Open Map File.2. Select the name of the map file to load.3. Click OK.The area that you bookmarked is now displayed onscreen.Map file bookmarks are used to identify a general location. They shouldn’t beused for marking a very specific set of coordinates, such as a GPS waypoint.Saving Aerial PhotosAfter you have an aerial photo or map displayed onscreen, you can save theimage to use with other programs: From the File menu: Choose Copy to Screen.jpg. This saves a copy ofthe aerial photo or map currently displayed onscreen to a file namedScreen.jpg in the same folder that USAPhotoMaps is installed in. Print Screen: Press the Print Screen key to save the current image to theClipboard. If you want to save only a portion of the map or aerial photothat appears onscreen, read Chapter 17 for practical tips on saving andediting images. BigJpeg: Use the BigJpeg utility. Doug Cox has a free utility that creates asingle, 1-meter resolution, JPG format graphics file from a photo or map.You define the boundaries of an area you want to save in USAPhotoMapsand then run BigJpeg to create the graphics file. You can downloadBigJpeg, with complete instructions, at http://jdmcox.com.After an aerial photo or map is displayed onscreen,that data now resides on your harddrive. USAPhotoMaps doesn’t discard old datafiles as new data is downloaded. If you’ve alreadydownloaded a series of photos and maps for ageographic area, you don’t need to connect toTerraServer-USA again to access that data. Theonly limitation to the amount of photo and mapdata you can have is the size of your hard drive.Saving strategiesUSAPhotoMaps writes all the data it gets fromTerraServer-USA to a single folder, so you cancopy that folder and its data to a CD or DVD. Thisis an excellent way to access aerial photos andmaps on a number of different computers thatmight not have an Internet connection (such aslaptops in the field). The USAPhotoMaps onlinehelp has instructions on how to do this.