Aerial Service FAQ
Aerial Photography Service FAQ
Where did the photos come from?
The MAP Library began building its aerial photography collection under Ed Thatcher, the original UO MAP Librarian, but developed the collection most strongly under Peter Stark in the late 1980s through the end of the 1990s. The original intent was, and still is, to support the teaching and research programs of the University of Oregon. The images were mostly gifts from the Oregon offices of federal agencies, as well as state, county, and municipal agencies. Some photographs were also purchased from commercial vendors.
Where did the topographic and nautical maps come from?
The UO Map Library has an extensive collection of historic topographic maps of Oregon as well as Oregon nautical charts which we have collected and preserved over the years. We are now able to provide digital copies for both academic and public users for urban areas in in the Willamette Valley. We are able to implement this service as we have designed a model for acquiring and storing historical materials once analog. In addition to the 15 minute topographic series, users can request research and duplication of topographic maps from the 30 minute and the 1 degree series as well. See our topographic web pages for the collection holdings.
Why can't I use the collection directly?
The Air Photo collection contains more than 600,000 individual frames of imagery from more than 1000 individual flights. Most of these images are irreplaceable. Due to the complex structure and historic nature of the collection, we must restrict access to staff only.
Why does it sometimes take 3-4 days to fill a request?
As an academic institution whose primary purpose is to serve students and faculty, we always give priority to academic requests. In some cases, this may cause a delay in the typical 3 day turn around. While we process the requests in the order that they are received, we have to adjust our time based on the availability of research assistants, the amount of ongoing academic research, and other library-related work. We would never be able to fill each request as it comes in. While we strive to return requests in 3 business days, as the volume of requests waxes and wanes, we may occasionally require that extra day.
Why can't I give you a tax lot number?
This information certainly helps, but tax lot boundaries, in addition to not being visible on a photo, vary widely through time. When you request a photo, your site is identified on a contemporary map, which is then matched to the historic indexes, which is then matched to individual photos. Looking up tax lots and PLSS coordinates would greatly increase the time it takes to identify a site and therefore increase your costs.
For some sites, we can accept geographic coordinates instead of a map. They should be of the format: XX.xxxx YY.yyyy. Contact us for details.
What's the best kind of map to provide with my request?
A USGS 1:24,000 topographic map or an image from an online map service such as MapQuest works best. We have an online guide to creating a simple map in Google Maps and some other sample maps. Please make sure to provide us with some context around your site. Sometimes it is helpful if you send maps at 2 different zoom levels. If you send a portion of a USGS Quad, please make sure to tell us the name of the sheet in case we need to look at our copy.
What's a 'Phase 1' request?
Many of our customers are working on environmental assessment reports for land purchases or development permits. We have adopted this terminology from them. A Phase 1 request yields historic aerial images with maximum 10 year intervals between photos, or as close to 10 year intervals as our collection allows. If you have more specific year requirements or or intervals required between photos, you can indicate that in the Special Instructions area of the request form, or contact us to consult on your request. The following terms describe the different patterns of years we routinely provide:
- Phase 1: 1 photo per decade
- Phase 2: about 2 per decade or 5-7 year intervals
- Phase 3: all available imagery (excluding same year photos)
Why do most Phase 1 requests (1 photo per decade) cost the same?
A typical Phase 1 request is $110, and a Phase 2 is $140, but this figure will vary based on the number of photographs retrieved. Detailed information about the service, along with links to more information, is on the Map and Aerial Photography Research Service homepage. These amounts have been calculated based on how much it costs us to provide the service each year. We are obligated by Oregon law to recover our operating costs. We must recover the time it takes to: initiate a research request, find the photographs, scan each photo, refiles photos, and maintain the collection.
Why might a Phase 1 request cost more?
Phase 1 requests most often cost more due to large areas of interest or increased scanning resolution. Large area requests will sometimes require multiple frames to cover the entire site, and we charge per item (including per frame) for scanning. Anything that complicates a request will add time to it, and ultimately we are charging for the time of our labor. Indeed, we are required to do so. Incomplete request forms, hard to read maps, and changes to requests mid-stream are all issues that may result in our imposing our hourly research fee.
What happens to the money?
Because 90% of this scholarly resource's use comes from non-academic users, we must recover the costs associated with these requests. Fees cover a portion of staff salaries, supplies for storing and maintaining the collection, and computer equipment used to scan and deliver the photos. We do not profit or subsidize other library services with the service fees. Because of the non-profit nature of the operation, our fees are considerably less than commercial air photo providers.
Can you give me more information about a photo?
Standard requests come with the year embedded in the file name. The standard file name format is as follows:
[Year]_[Project Code]_[Roll #]-[Frame #]
Here is an example of a file name for an image produced by the USGS:
Exact dates and scales are sometimes not available, but whatever information we have can be obtained upon request. If this additional information is needed, you may indicate that in the Special Instructions area of the request form. Typically there is no charge for providing basic additional information such as scale, exact date, and agency. If a great deal of information is needed, requiring extensive research, the hourly research rate might apply.
What can I do with my photos?
- You may store your images indefinitely, derive new data from them, and give the photos to your own clients. We understand that copies of the photos are included in environmental assessment reports and other research products. We do not consider this to be 'publishing' the photos.
- If you would like publish a photo in a book or online, please contact the MAP Librarian to negotiate a publication license for our imagery.
- While the photographs are yours to do with as you please, the University maintains copyright over the electronic versions and some of the source imagery. We never sell copies of photographs to which we do not hold the rights to do so.
Digitization of photos -- Scanning Resolution and ground pixel dimension
When we scan aerial photos from the collection the resulting pixel ground dimension (the equivalent size/volume of the pixel on the ground) varies because of the differing scales of the photos in the collection. Below is a table that provides pixel ground dimension for the most common scales and the most common scanning resolutions we provide.
Formula for ground pixel dimension
Scale of photography ÷ 12 inches ÷ dpi resolution = ground distance per pixel
Pixel Size (Ground Dimension --in feet --of a pixel)
Scale of Photo