Creating a Map with ArcMap - Tufts University

Downloading image data from MassGIS
• Now go online and go the MassGIS web site: http://www.mass.gov/mgis/
• Click on the Download Free Data link
• There is information here about how to download if you need it. If you are familiar with
downloading files, go the Download Image Data link and read about the available imagery and
scroll down the page to see what is available. You are going to download a 1:5,000 Digital Ortho
Image for 2005 and a Scanned 1:25,000 USGS Topographic Quad Image (DRG)
• In the 1:5,000 Digital Ortho Image (2005) section, click on the link for MrSid – MrSid is an
image compression format that retains good resolution
• You will see all the files for Massachusetts - scroll down to find the sheet id you want and select
all the files with that sheet-id
• Download these to your personal folder along with your other GIS data by right clicking on each
file and selecting “save link as” – you MUST get all the files with the sheet-id – the .sid file is the
image itself, the .sdw file is the file that gives it the correct location, and the .aux file helps it to
draw quickly. The files will take several minutes to download
• Now go back to the image data web page and download the same sheet-ID for the Scanned
1:25,000 USGS Topographic Quad – again, use the MrSID link (note that the quad maps start with
the letter “q” but have the same sheet ID after that).
• Download the .sid, .sdw, and the .aux files beginning with q233902 by right-clicking on each file
and selecting “save link as”
Another Option: Downloading image data from the M: Drive
• If you are working in the GIS Lab, you can download orthophotos on the M: drive by drilling
down to the MassGIS imagery folder - M:\State\MA\MassGIS\Imagery\Orthos2005\Sid)
• Click on Name at the top of the Name column to sort by name.
• Select the files you need (as shown below) and save them to your personal folder.
• As of 1/30/07, Scanned 1:25,000 USGS Topographic Quads are not available on the M: drive.
You will have to get these from Mass GIS as instructed above.
Opening the orthophoto in ArcMap
• Return to ArcMap and add the orthophoto to your map (choose File - Add Data or use the Add
Data tool). If when you are navigating to your orthophotos file, and you see three choices (band1,
2, 3), you have gone a click too far - go back up to the folder just above it and you will see just
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