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Expanded and Adapted from Columbia University Libraries (2010) "Georeferencing an image in ArcGIS," Accessed August 2, 2010 from http://www.columbia.edu/cu/lweb/indiv/dssc/eds/georef.html  All information indicated by an asterisk (*) is taken directly from the Columbia University tutorial without change.  Other items may have been changed or adapted as necessary.

Georeferencing is the process of aligning spatial data (layers that are shape files: polygons, points, etc.) to an image file such as an historical map, satellite image, or aerial photograph.  This document describes the basic steps for Georeferencing an image using ArcGIS.*

Add an Image to the Map Project

  1. Click on View → Toolbars → Georeferencing  
  2. Add the image you want to Georeference to your map project.

Raster images - such as .jpg, .tiff, or .png files (all of these are image file types), are actually made up of multiple layers.  Click once on the name of the image file and then add it to your map project.  If you double click on the image file when using the Add Data feature in ArcMap, you will see something like this:

Raster Image Band Layers

The 3 bands represent layers that make up the image file. You can see the name of the file in the Look In: field at the top of the dialog box.  To successfully add the file as a single, unified whole, do the following:

  1. From this view, click on the Up One Level button Up One Level Button .
  2. You will see the file name of the image again. Simply highlight the file name by clicking on it once.
  3. Click Add to add the file to your Map Project.

Control the Image Size and Position in the Map Project

The Scale Tool

Many times, images added to a Map Project appear so large in the Data Frame (the main viewing area) of ArcMap that they cover the entire viewing surface.  You can re-size the image by using the Scale Tool in the Georeferencing Toolbar.

Scale Tool

Make an Image Smaller
  1. Select the Scale Tool from the Georeferencing Toolbar.
  2. Move the cursor to the corner of the image.
  3. Click and drag from the corner to the center of the image.
  4. Release the mouse. The image will resize.
Make an Image Larger
  1. Select the Scale Tool from the Georeferencing Toolbar.
  2. Move the cursor to the center of the image.
  3. Click and drag from the center to beyond one of the outside edges. The further outside the edge of the image you drag, the larger the image will become.
  4. Release the mouse. The image will resize.

The Shift Tool

You can move an image file around the Data Frame using the Shift Tool to reposition it for the purposes of viewing Control Points on your image and Basemap simultaneously.

Shift Tool

  1. Select the Shift Tool from the Georeferencing Toolbar.
  2. Click and hold the mouse on part of the image.  Drag the cursor to the desired area in the Data Frame.
  3. When you release the mouse button, the portion of the image on which you clicked and dragged will move to the area where the cursor was when you released the mouse.

The Rotate Tool

To orient an image, use the Rotate Tool to turn the image to match a Basemap. (If you are using Visual Cues to Georeference your image).

Rotate Tool

  1. Select the RotateTool from the Georeferencing Toolbar.
  2. Click and drag the image to rotate it in the Data Frame.
  3. When you release the mouse button, the image will rotate.

Add Control Points to Your Image

The Add Control Points tool is the tool that allows you to georeference the image. This is the process of matching points on the image layer to corresponding points on the shape layers.

Add Control Points Using Latitude and Longitude

You can enter x (longitude) and y (latitude) coordinates as Control Points rather than use the method mentioned above. To do this,

  1. Left click on a known point on the image. This will place a cross mark on that location.
  2. Right click on the point you just created. A menu will appear.
  3. Choose Input X and Y. The Enter Coordinates dialog box will appear.
  4. Enter the coordinates in the appropriate boxes.

Add Control Points Using Visual Cues

Control points can be added using visual cues. These usually take the form of visible landmarks, like the corner of a sharply defined agricultural plot of land, or the bend of a river.

Note: it is a good idea to zoom in on your image when adding control points for better accuracy.*

  1. In the Georeferencing pull down menu, make sure that Auto Adjust is turned off (no check mark).
  2. Add a Georeferenced Basemap to your new Map Project.  We recommend adding the ESRI Imagery World 2D Map or ESRI Street Map World 2D from the ESRI servers.
  3. In the Table of Contents, drag the Basemap below the image you are georeferencing. That will allow you to see the image superimposed on the Basemap.
  4. Select the  Add Control Points button
    Add Control Points Button


  5. Left click on a known point on the image. This will place a cross mark on that location.
  6. Left click on the matching control point in your Basemap. Create a companion point on the Basemap.  The two points will be connected by a bright, blue line.
  7. Repeat steps 5 & 6 with each control point.
  8. When you have finished adding Control Points, select Transformation from the Georeferencing pull down menu. 

*Depending on the number of control points you have, from the Georeferencing table you can perform either a 1st, 2nd, or 3rd order transformation. The transformations compare the coordinates of the source image with the control points creating two least-square-fit equations to translate the image coordinates into map coordinate

  • A 1st order transformation shifts the image up, down, right, or left, stretches the image larger or smaller, or rotates the entire image
  • The 2nd and 3rd order transformations fit higher order polynomial equations to the data, allowing points to be shifted in a non-uniform manner
  • Most of the time either a 1st or 2nd order will suffice, try all three and choose the one that works best

For every set of control points you create, an entry is created in a table that records the original coordinates, the control point coordinates, and the residual error. Access the table by choosing the View Link Table icon from the Georeferencing toolbar

Entries in this table can be deleted one at a time (highlight the entry in the table and click the delete icon) thus making corrections is easy.

Saving changes

Choose Rectify from the Georeferencing pull down menu

When you are satisfied with the georeferencing process, three options for saving changes are offered:

  • As a text file - you can load the text file when you need to have the image georefenced again:
    From the Link Table select Save
  • As a .aux file - this saves the changes in a file readable by ESRI products
    From the Georeferencing toolbar select Update Georeferencing
  • As a World File - this creates a new image (either TIFF, ESRI Grid, or ERDAS Imagine) with the coordinates stored. Use this option if you plan on using the image with other software
    From the Georeferencing toolbar select Rectify
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