People in Oklahoma know that the state's geography is vast and diverse. People wanting to study that diversity can view satellite images that were taken of Oklahoma in 1995. This tool shows how the images can be accessed in order for learners to see the changes in their community from 1995 to 2000. (New satellite images were created in 2001 to compare with the previous images.) Note: ArcView, which provides access to the images, works only on Windows operating systems.
Internet Explorer 4.0 or Higher
Microsoft Internet Explorer 4.0 or higher is required.
Netscape 4.0 or Higher
Netscape 4.0 or higher is required
ArcView 3.1 or Higher
ArcView 3.1 from ESRI is required to view the orthographs.
The Digital Atlas of Oklahoma
The Digital Atlas allows you to identify which orthophotograph you wish to view. The atlas is available for purchase or for download at the SEIC web site. More information is available from the Digital Atlas of Oklahoma Toolkit.
Ortho Image Maps
Use this form to share your "place" using orthophotographs.
FTP Explorer
FTP Explorer is another way to access the orthophotographs with a
Windows 95, 98, or NT format.
Internet Connection
An Internet connection with a high speed modem or T1 line.
ArcExplorer GIS Toolkit
For novice users of GIS programs, this ALCA tool covers the basics of adding themes to views.
LizardTech Resources
LizardTech, which creates the MrSid image compression technology, has free resources for MrSid image viewing online at their web site.
Open ArcView 3.1 and click on the radio button "With a new view." When the dialog box asks if you would like to add data to the view, click "Yes."
Place the Digital Atlas of Oklahoma into your CD-ROM drive. Access the data for your county and add the "roads" and "quad24" themes. Click OK. Turn on the themes (a checkmark will appear next to the themes).
When the Quad24 theme is viewed, it resembles several large rectangles. Click on the theme in the left column to make it active. A border will appear around the theme. Use the information cursor (the icon with an "i") and click on the rectangle you wish to view. A dialog box will appear. Scroll down the right column until you see the cell "Index Code." REMEMBER THIS CODE!!! This allows you to view the data on the FTP site.
The index code will resemble something like this: 36097-H3. The 36 stands for "36 Degrees North Latitude," and 097 stands for "97 Degrees West Longitude." The H3 stands for the location of the quadrangle according to the USGS Quad Map Grid (shown below). To continue, close ArcView.
Open your browser (Netscape or Internet Explorer). In the location bar, type in the site ftp://okmaps.onenet.net/doq/, and push the ENTER key.
Internet Explorer 5 Users: If an error message appears, right-click in the window. Click on "Login As..." Click on the "Login Anonymously" checkbox, and click "Login."
You must now open the correct folder to view the orthograph. From the Index Code, locate the first five (5) numbers of the code. The first five (5) numbers in the index code is the folder name. (Example: In the code 36097-H3, click on the folder /36097/.)
Scroll down to the bottom of the page. Click on the "/mrsid/" folder.
Internet Explorer 5 users will need to double-click on the "mrsid" folder.
Using the Index Code, find the ACTUAL codename in the FTP directory tree. They are separated into four quadrants. (Example: For the index code 36097-H3, find the files 36097h31, 36097h32, 36097h33, and 36097h34.)
Each quadrangle is divided into four equal squares. Below are the locations of each quadrant.
Quadrant 1 = Northeast Section
Quadrant 2 = Northwest Section
Quadrant 3 = Southwest Section
Quadrant 4 = Southeast Section
The files coincide with the quadrants. (Example: 36097h31 = 1st Quadrant)
Download your files by right-clicking on the .sdw and .sid files (Mac users, hold down the mouse button) and clicking on "Save Link As..." ("Save Target As..." for Internet Explorer 4.0. Internet Explorer 5 users will click on "Copy to Folder..."). The total size for both files is 2.5 MB.
EXAMPLE: For the file 36097-H3, and you would like the northeast quadrant, you would download the files 36097h31.sdw and 36097h31.sid.
Be sure to download these files one at a time. If not, you will not be able to use the data.
Close your browser after you have finished downloading all of the images that you need. Open ArcView again and create a new project. When the dialog box asks if you would like to add data, click "No."
Go to File/Extensions... In the dialog box, scroll down to the check box next to "MrSid Image Support." Click on the check box to make a checkmark appear. Click OK.
NOTE: Unless you save your project, you will have to repeat this step every time you want to access your images.
Add a theme. Change the "Data File Types" box to "Image Data Source." Go to the folder with the downloaded files using the directory tree in the right column. The files should appear in the left column. Click on the files you wish to open. Click on OK. The themes will appear in the view.
Now that you have your themes viewed in your project, click on the check box. A checkmark will appear, and your images will appear. There may be a short delay.
NOTE: Save the project if you wish to access these images at a later date.
NOTE: These images are VERY intricate and detailed. The image shown below is the view of the entire image. You can zoom in a lot closer than what is shown below.
If you are a student, consider zooming down to your school site to veiw the buildings there. If employed consider looking for your work place. After zooming down to an level that is clear to see all buildings, add other desired themes. Export the map as a jpeg and save to your computer.
Share your image in the Ortho Image Maps form attached to this tool. You will need to know the location and description for the map.
Orthophotographs of Oklahoma are a great way to teach and enrich geographical awareness in the classroom. You can learn about geographical changes in your community as well as create maps of your town. You can also learn about the importance of township ranges and sections by viewing the rural road "squares" that were created during the Land Runs of the 1860s-1890s.
Please enter a Registration Key to continue.