ESA Lab FAQs, Helpful Hints, and Troubleshooting Tips
general |
education | GIS
| remote sensing | other technology Qs
general
- Q: What does the University of Michigan offer in terms of support for
users of GIS?
The University Library's
Spatial And Numeric Data services (SAND)
offers a lab,
assistance finding and using data,
tutorials,
and one-on-one and group
instruction. It is open to all faculty, staff, and students. The
Center for Statistical Consultation and Research (CSCAR)
also offers Spatial / GIS user support along with help
regarding campus-wide GIS software licensing and installation. In addition individual
departments/schools sometimes have additional support for their communities e.g. the School of Natural
Resources and Environemnt has the Environmental Spatial Analysis (ESA) Lab.
- Q: What does the Environmental Spatial Analysis (ESA) Lab offer in terms of support?
The ESA Lab offers free consultation and workshops to the SNRE community and research affiliates on
topics relating to GIS, GPS, remote sensing, and spatial analysis. The ESA Lab also offers hourly
service and support for clients within SNRE and UofM and for clients outside of UofM. Contact the ESA Lab Manager for details.
- Q: Does the Unversity of Michigan have a mechanism whereby people can
easily share spatial data sets with others who might be interested in
them?
Yes. The UM Library's searchable online
Digital Spatial Data Catalog
has links to a data repository; all are encouraged to submit data sets to
it. These data sets might be ones you have created or modified or might
be data sets you've found and would like others to know about. As with all
community efforts it will work best if community members contribute!
Contact spatial-data-access@umich.edu for assistance.
education
- Q: What does the University of Michigan offer in terms of GIS and Remote Sensing education?
Please visit the ESA Lab's education page
for more information on: GIS/RS courses offered through the School of Natural Resources and Environment
(SNRE) and the University of Michigan; workshops offered through the ESA Lab, CSCAR and NSDS; and the graduate
certificate program in Spatial Analysis.
- Q: Is there a tutorial I could go through to get acquainted with GIS software?
Yes. Both ArcGIS and ArcInfo are distributed by ESRI.
From their web page, click ESRI Virtual Campus, and from there navigate through the GIScience,
GIS Technology, and GIS Applications courses. Most courses from the ESRI Virtual Campus are available at no cost to
University of Michigan faculty, staff and students. See the
"Online GIS
Training" page hosted by CSCAR for a listing of courses available for free
and for enrollment instructions. Also, an introductory tutorial and others are available from
the University Library's Spatial And Numeric Data services at
this link. Staff at SAND can
also provide assistance with the use of these tutorials.
GIS
- TIP => Launch the HELP system as soon as you open any GIS package.
- Q: Where can I acquire public data?
First check the UM Library's searchable online
Digital Spatial Data Catalog.
The State of Michigan maintains a
MI Geographic Data Library. The
Southeast Michigan Council of Governments (SEMCOG) is a regional planning partnership
that offers GIS data for souhteast Michigan. Digital line graphs (DLGs) and Digital Elevation
Models (DEMs) are available for the United States through the
U.S. Geological
Survey (USGS). The Geography Network is also a decent
place to start.<
- Q: What about projections? OR Why don't my files overlay properly?
All data you are working with in a project must have the same datum, projection, and
coordinate system! A telltale sign that they do not is that data don't overlay as they
should. So, the first step in organizing a project should be choosing a consistent datum,
projection, and coordinate system for all your data layers. Check the on-line documentation
for guidance with this.
From the Geographer's Craft
web site: 'Map projections are attempts to portray the surface of the earth or a portion of
the earth on a flat surface. Some distortions of conformality, distance, direction, scale,
and area always result from this process. Some projections minimize distortions in some of
these properties at the expense of maximizing errors in others. Some projections are attempts
to only moderately distort all of these properties.' This site has a lot of information on
projections, as well as the closely associated topic of
coordinate systems.
Arc/Info-specific stuff
- TIP => The first step each time you launch Arc/Info should be connecting to a workspace.
A workspace is a directory containing geographic data sets and the associated INFO files for use
with Arc/Info. Connecting to a workspace tells the program where to look for the INFO files and
update the geographic data. Follow these steps to connect to a working directory in workstation
Arc/Info:
* launch ArcCatalog
* click the right-pointing arrow
* navigate to the appropriate directory on the left
- Q: What is an arc interchange file (.e00)?
Arc/Info interchange files (.e00) have become the de facto standard format for the transport of
Arc/Info files.
Because "coverages" are are actually bundles of files, Arc interchange files are used to transfer
coverages, INFO data files, text files such as AML macros, and other Arc/Info files between various
machines as a single entity with all the files included. Arc interchange files can easily be
converted back to coverages in Arc/Info by launching ArcToolbox then navigating to Conversion
Tools => Import to Coverage => Import from Interchange File and entering the approrpiate file.
remote sensing
- Q: How can I obtain and import public satellite imagery data?
MODIS Acquisition and Import Instructions | Landsat Acquisition and Import Instructions | ASTER Acquisition and Import Instructions
- Q: What remote sensing software does the ESALab have?
Remote sensing software has considerably more capability for working with raster data files than
do GIS software packages. If you are working with images consider using one or more of the
following software packages: ERDAS Imagine 8.6 Professional
(only available to the SNRE ESA Lab),
PCI Geomatica 8.0 (available to install campus-wide, see http://gis.umich.edu), and Idrisi 32 (available to install campus-wide, see
http://gis.umich.edu).
TIP: The vector module in ERDAS Imagine is the same as the ARC/INFO vector module, so ARC/INFO
vector files are compatible with ERDAS Imagine.
NOTE: Workshops are held for the SNRE community that give a brief introduction to ERDAS Imagine.
Also, Remote Sensing of the Environment (NRE 441) is a good introductory course in remote sensing
using ERDAS Imagine software.
- Q: Is there an affordable remote sensing software package?
Yes, Idrisi has an education package
that is reasonably priced. The program functions much like ERDAS Imagine and is similar in terms
of capabilities.
- Q: Where can I acquire public data?
Following are some good resources for public remote sensing data:
Michigan air photos =>
MI Geographic Data Library
U.S. air photos (high altitude; relatively inexpensive) => U.S. Geological Survey (USGS)
satellite imagery => Landsat 7 imagery
NOTE: Landsat 7 data cost approximately $600 per scene and some planning is required to acquire the
appropriate scene at the right time, depending on your study needs. Prices vary for older Landsat data;
these can be found using the EarthExplorer
or searching the University of Maryland Global
Land Cover Facility's (GLCF) database. The GLCF has some data available for approximately $380 + shipping
and also maintains a library of Landsat scenes available for free download.
- Q: What is HDF format and how do I import an HDF-format file into Erdas Imagine?
HDF is a physical file format that allows storage of many different types of scientific data, including images, multidimensional data arrays, record oriented data, and point data. Follow this link to a step-by-step guide on HDF data import (e.g., Landsat ETM+). Note: Always check the most recent version of the software you are using, because software updates often include support for new file formats.
other technology Qs
- Q: How do I access and install spatial analysis software?
The spatial analysis software packages available for installation reside on the Center for Statistical Consultation and Research (CSCAR) server. They operate a web site that details the procedure.
- Q: Where can I get more information on University of Michigan technology?
A good site for University of Michigan-specific information is operated by the university
Information Technology Division (ITD).
- Q: How do I restore a file that was on the SNRE network and was accidentally deleted or corrupted?
Depending on how long ago the file was there, the SNRE IT consultants may be able to help you. Go to
http://www.snre.umich.edu/help and look under "Network Services | Data backups and restorations" for more info.
- Q: What options exist for accessing the SNRE network data server?
Go to
http://www.snre.umich.edu/help and click on "Accessing files on SNRE5" for details. Also see the question regarding
mounting the SNRE data server under UNIX above.
