NZRM Field Testing 2023-08-05: Volumes vs MapBooks

UPDATE: It has now been decided for various reasons that MapBooks will stick at diagrams only. Full aerial coverage will continue to be available in the existing Volumes and also an A4-based current aerial format that is produced alongside the MapBook pages that users can print out themselves.

Field testing is where the project’s productions get tested in the real world to see how useful they are in various situations. This is the second full day test of NZRM map productions. It was not set out to be that specifically, but that is what it ended up as on the day. The Midland Line maps (Volume 7) from Rolleston to Otira were tested in the Volumes format as recently completed and last updated the day before. Specifically, this included all of the content listed on the Volume 7 page (image based maps and GPX file) used on handheld devices.

The last proper field test was carried out on 2021-02-24 as you can read here and was successful in validating the Volumes image-based maps using just a subset of the available map content and GPX file for the Main North Line whilst traveling on the Coastal Pacific Express. The Volumes map content in its current format is most useful for people traveling by train who want to know about the route they are riding along and the history of each station they pass. Volumes content is very detailed so a subset of the content might be more useful in some contexts, however it is quick and easy to swipe through the images on a phone or tablet and keep up with the journey so it is not too much of an issue and users could choose to subset the content (for example diagrams). The Volumes format will always offer the maximum amount of detail for the complete corridor(s) as it is very simple and cheap to provide the content in this format, currently free of charge. In order to track current position the GPS file loaded into a separate map app or in the case of the 2021 field trial, purely used on a handheld GPS, has been shown to be very straightforward particularly outside cellphone coverage areas. A GPS that has built in street maps would be even better, this not being the case with the low cost GPS units used for the field trial. In this month’s field trial a cellphone with the Osmand app loaded was used with the GPX file for handheld navigation and was aided by the continuous coverage (for OneNZ) all along the SH73 highway corridor.

The Volumes format is less suited for road traversal of corridors because of the breaks in continuity when navigating from station to station (as will typically be the case for a field trip) and for this type of situation, the printed format of maps offers the great advantage of being able to quickly move randomly through content without the issue of attempting to locate station sites from small thumbnails on a device, although one option that is being considered is to place index markers within volume image sets for each station location. A secondary issue that is important for road based trips is the challenge of viewing images outdoors on a hand held device with the inevitability of screen washout due to lighting conditions. For this reason it is felt that the MapBook printed format will be trialed for the next field trip. Here is one of the options looked at so far.

There are still lots of questions to answer and solve before being able to determine the appropriate format for any type of printed volume. A key issue is that the practical limit in size for a printed volume is about 380 pages (190 sheets printed both sides) with a plastic spiral binding. Each volume in NZRM as they are currently formatted covers 500 km. A lot of work will be needed to work out how the full content of a volume can be fitted into 380 pages. The above is 8 A4 pages for one station at a scale of 1:1000. Between stations the scale would be as low as 1:50000. In essence as there is more than 1 km per page, the practical size of each volume will determine things like scale since, for the above examples, Darfield needed 9 pages to display the most useful details. A 380 page volume would cost about $65 for a single issue, but they will be cheaper if printed in multiples. The next step of the trial is to produce the A4 page format as above for the completed sections of the Midland Line to date and see what sort of page count can be averaged over a longer distance. Previous estimations however were that either a larger number of volumes would be needed (the original format of NZRM was for 26 volumes) or else printables were to consist only of diagrams, which is possible within the scale. It may turn out to be the case that for a printable format, it is only practicable to produce two diagrams per A4 page for a volume, with no aerials included. The format shown above is an attempt to abbreviate the highly detailed Volumes image formats, which cover every available generation of aerial photography, into a diagram and most recent aerial, but there is a distinct possibility of there being merit in further combination or abbreviation that will have to be explored.

So the other option likely to be considered will be the following, this time of the old Springfield station. Printed at a slightly smaller scale of 1:1500, it would halve the number of pages needed for a station layout (there are fewer pages in this instance because of the smaller station footprint).

As long as the print quality (in black and white) can meet expectations then that is the acceptable alternative. If print quality is not up to scratch then diagrams are what will have to be taken as the best option for a mapbook format overall.