North Auckland Line [0K]: Volume 1 Progress Update 11

Good evening and here is our latest progress update for Volume 1. We are making good progress on updating our mosaics to ensure they are more accurate which we are achieving by using the centre 40% of each survey image for the NZR station surveys that in Auckland City also cover complete corridors in most of the Auckland suburban area. Previously the system used was to skip every second source image. However, taking the centre part of every source image ensures there is less distortion visible in the ground features and is therefore important in ensuring greater visual accuracy of the historical aerial mosaic tiles in the GIS. This has generally worked well for the station surveys with only one case so far of having to adjust the boundaries of a layer. The 40% figure is about right with the overlaps in most cases being quite small except where a new run comes in for a change of direction, but it may need to be adjusted for station surveys outside Auckland which are generally at a smaller scale, and particularly for corridor surveys which are smaller again and tend to be more spaced out, or highway surveys which are smaller still; we haven’t done any of these yet. Gimp lets us bulk crop a whole lot of source layers together and preview and adjust the crop margins easily.

We have now completed about two thirds of the aerial mosaics for the Auckland suburban area and are pushing on to complete the rest as quickly as possible. Until that is finished, no map drawing will take place. However, once the mosaics are ready, we expect to be able to press on quite rapidly in drawing maps to the Basic+ standard as the historical aerials will not be used to source any content for the diagram form of maps except in three previously defined areas. We will not be revising historical aerial content for outlying rural areas to the new standards except possibly for Whangarei as a larger area that would benefit more from a revision than smaller rural stations that have already been completed and their content captured some time ago.

We had expected greater progress by this point but have had to reschedule due to other demands on time and as these demands are expected to become permanent, it is therefore necessary to ensure that we manage our time on the project more effectively. This therefore is a time to confirm our earlier statements about limiting the volume of additional historical aerial content to be produced for the maps. It will be limited to the areas described in our last update and so far we have not looked in depth into available aerial coverage for any of those areas. We currently plan to push ahead with firstly updating maps for all of the North Auckland Line corridor as far as Waitotira, the junction for the Dargaville Branch, take a look at the Dargaville Branch aerials, then complete that section, continue northward to Otiria, then look at the Okaihau Branch aerials mentioned and complete that section and any other unfinished sections.

Current schedule is to have the Auckland area mosaics finished by about the middle of next week and the drawing of maps for the Auckland suburban area, or basically Westfield to Waimauku and the two branches, completed by the end of next week, so about another week. We have also decided to set a deadline for the entire Volume 1 update to be completed by the end of June. This is quite a bit later than originally planned, but has to be seen as a necessary shift in our schedules due to additional and permanent increased demands on our time from elsewhere.


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