. >> the planning department has three that are as of yet unconserved. >> what does that mean. >> we have not had the time or resources to digitize them. they're very large. more than this book here. they're about 32 inches square and cover the whole city in 1948 to 1950, somewhere in the mid 50s or 60's. >> to go on the resources that are available to us there's aerial photography that goes back to the -- actually pre first world war and they're amazing and held by pacific ariel survey off,,hagen burger road by the airport. what they did in the early era is they had a large format cameras that they went with the originals over the city and did long exposure photos with very high resolution lenses so when you want to find something in the archives, they'll give you aqua drant go to and a loop and you can't see much resolution but they will blow it up for you and the resolution will be so high you will be able to determine the make of many of the autos you see on the street. in the teens and 20s. >> so let's go back to learning history of your building to find out when was your buildi