Sunday, 17 May 2015

Otago Central Railway maps revision

At the moment I am revising these maps and the Flickr album which currently only contains the Cromwell Gorge maps will be revised to include all the maps. Previously a map volume was also produced which is available for download in the Google Drive section of the NZ Railmaps.

Look for “NZRM Vol17 Otago Central. The 71 page PDF is dated from January 2013 or about two years ago. It contains about as much tabulated data as I was able to find about the different features of the line to date and is somewhat more comprehensive particularly in bridges than Over the Garden Wall, but omits the descriptions for obvious copyright reasons.

I am now enquiring for aerial photography, starting with the Cromwell Gorge and possibly extending to the rest of the line in due course, but this will be very dependent on the cost and may well be limited to specific areas such as the stations. The first survey from the Cromwell Gorge appears to date from February 1962 and probably informed the first NZMS1 map production of c.1970. Also it’s unlikely the higher resolution topomaps (1 inch to half a mile) would have been completed for this area. The aerials for 1962 were taken at a scale of 1:8800 and their usefulness naturally depends on how sharp the footage was therefore how big it can be resolved to. The description from the LINZ website reads:

Note: LINZ and Opus International have recently agreed a contract for the maintenance of the Crown aerial imagery archive, following the liquidation of New Zealand Aerial Mapping in September 2014.

The following Information on product sales has been updated to reflect this.

This layer has been provided to enable potential users to identify the coverage of photography for Mainland NZ flown on behalf of the Crown between 1936 and 2005. Areas flown outside of Mainland NZ will be added later. The layer shows the extent of each photograph taken. The 'NZ Aerial Survey Footprints 1936-2005 poly' layer shows the extent of each survey undertaken.

The Collection exists as photographic negatives (most are not in digital form) so the images are not downloadable from the LDS.

The Crown Aerial Film Negative Collection is managed for LINZ by Opus International.

You can are order images from the Collection from Opus International in a number of formats, including:
- contact prints
- enlargements
- digital files
- precision scans for photogrammetric production
- orthophotos

You will need to tell Opus International the survey, run and photo number (values in the ‘SURVEY’ 'RUN_NO' and 'PHOTO_NO' attributes) covering your area of interest.

Opus International will be able to provide information about the cost of providing images in the various formats. Contact them at: or 0800 680 690

There are a small number of images held in the Collection that have not been referenced in the LDS layers due to incomplete metadata. LINZ is currently investigating ways this can be remedied. Opus International will be able to let you know if additional photographs are available in your area of interest.

There are also a large number of images which previously belonged to New Zealand Aerial Mapping and which are now are available for public use. The extents of these may be added to the LDS in future. You can order these images by contacting Opus International.