Another option might be to export the high-res imagery from Google Earth Pro and do the digitizing in a desktop GIS program. Although you can't export georeferenced imagery, people have developed quick workarounds (see for example, http://gis.yohman.com/up206a/how-tos/how-to-add-a-google-earth-satellite-image-into-arcmap/). This method works well for small areas. Cheers! Susan On Thu, Mar 2, 2017 at 10:00 AM, David Hodnefield <[log in to unmask] > wrote: > Hello Phillip. > > > > The National Archives and Records Administration may have additional > coverage of Chile. Someone has to research the coverage and then digitize > the film. I believe that NARA will do the research for you, though I am > not certain and it may take a long time. Someone would still need to > request and digitize the film. If visiting NARA II in College Park, MD > isn’t convenient, there are a number of companies that can do that work, > including mine. We all charge fees however. > > > > Good luck. > ------------------------------ > > [image: Description: cid:image001.png@01CD70F3.D84978F0] *limiting > liability with relevant environmental** research* > > > > *David Hodnefield, President* > > *Historical Information Gatherers* > > > > *[log in to unmask] <[log in to unmask]>* > > 952-253-2004 ext 111 <(952)%20253-2004> > > www.historicalinfo.com > > > > -----Original Message----- > From: Maps-L: Map Librarians, etc. [mailto:[log in to unmask]] On > Behalf Of Philip White > Sent: Wednesday, March 01, 2017 6:51 PM > To: [log in to unmask] > Subject: Aerial/Satellite Imagery of Chile > > > > Greetings, > > > > I am assisting a PhD student who is working on a GIS project quantifying > the amount of built structures within certain high risk zones in several > small municipalities in Chile. Neither he nor I have found building > footprint data (OSM has some, but very incomplete coverage in these areas), > and now he’s looking at heads up digitizing –which seems feasible because > most of his zones are rather small and not densely developed… a test of a > zone ended up having <1% human-made structures… Others could have up to 15% > maybe. > > > > At any rate, the snag is finding imagery at high enough resolution to > accurately digitize. I have searched USGS offerings on Earth Explorer, but > these are not current enough nor at high enough resolution. SPOT has 1.5 m > resolution imagery of the study area from this month, but it is $440 per > image. My institution has some sort of partnership with DigitalGlobe that > I’m trying to dig up more information on, but I think access is limited to > certain people. > > > > So, would anyone happen to know of alternatives for high-res imagery in > that part of the world? Is there a source I'm forgetting? Perhaps there is > a source of aerial photographs in Chile that I’m not aware of? > > > > Another idea is to just use Google Earth Pro, which could be used for the > heads up digitizing, and it has SPOT imagery for the study area dated > within the past 6 months –it looks pretty good. Google says people can use > Google Earth for non-commercial purposes. Does anyone have experience using > imagery from Google Earth for research purposes? On the other hand, drawing > polygons in Google Earth is not optimal: when you add a new individual > polygon it is a separate layer. The end result would be exporting a bunch > of single building footprints as individual KML files and merging them all > into one layer in Arc or QGIS –doable but suboptimal. > > > > Along those lines, the imagery available as a basemap layer in ArcMap is > dated (DigitalGlobe from 2010). We found new structures in the study areas > that had been built since then. > > > > Or maybe heads up digitizing is not the best option… I’m open to > suggestions. > > > > Thanks, > > > > Phil White > > > > _____________________ > > > > Philip B. White > > Earth Sciences and Environment Librarian, Assistant Professor Jerry Crail > Johnson Earth Sciences & Map Library University Libraries > > > > University of Colorado Boulder > > 184 UCB > > Boulder, CO 80309 > > > > 303-735-8278 <(303)%20735-8278> > -- Susan Powell GIS & Map Librarian UC Berkeley 510.643.2684 [log in to unmask]