- The first stage is to obtain the Linz aerial photography for a volume and then align the railway routes within that volume to the actual rail lines displayed on that aerial photography. For Volumes 1 to 11, these volumes are each based upon one existing main line rail corridor, so the alignment is being done for that main line. For closed branch lines and other rail routes in a volume, we are drawing upon all existing knowledge we have obtained elsewhere about the routes, which may be aided by visible features remaining on the ground that are visible in aerial photography.
- The second stage is to traverse the same routes in the opposite direction and mark in all useful features such as bridges, tunnels, stations and yards. These are all traced off the aerial photography. Our original plan for Basic level has been expanded to make use of Retrolens historical aerial photography for a station site as a reference source to mark in some features that may not be readily visible on current aerial photography. So in this stage the historical aerial photos will help to pinpoint the exact location of individual stations, many of which are closed today.
Once the information is all in place within the maps, they are ready to be produced (published).
Right now we are completing Volume 5 to a Basic level and have been working continuously on it for the past few days (of which more in another post shortly). So it looks like a week or two is what it would take to complete each volume to a Basic level. This will vary a lot as some volumes have already been completed at a Basic level, and others have been only partly completed. A lot of volumes were put together before we were able to get the use of the current Linz aerials and of course well before Retrolens came along, other volumes have Intermediate and Comprehensive level content that have been put into them as well. But for now, Basic level is what is happening first.
The maps in general (across all levels) are designed to be highly usable across a range
of different formats. The key assumption we have designed them to at the
very lowest level is that they will be adaptable both to modern
electronic devices and to hardcopy printed formats. For a handheld
device such as a tablet or phone, maps will be published
online in a photo album with navigational indications that enable
intuitive scrolling between tiles. We don’t have the means to publish
the maps in a digital globe format that can be hosted by a tile server,
so the tiles are put into a photo album and statically scrolled and
displayed one at a time. They appear at a variety of scales depending on
how much detail needs to be shown, so you will see a small scale where
there isn’t much information, zooming in to a large scale where there is
a lot of information such as a yard or siding layout that needs to be