Sunday, 15 July 2018

Wairarapa Line [5]: Haywards-Silverstream

Haywards to Silverstream is interesting because of various route changes. Haywards was originally reached from the first route of the Wairarapa Line up the western side of the Hutt Valley via Lower Hutt, Melling and Belmont. In February 1954 the Wairarapa Line was deviated to the eastern side of the valley so that Haywards (Manor Park as it became) was a junction until the old route was fully closed. The present Manor Park station is slightly to the south of the old one. 

Manor Park has recently had an overbridge built replacing pedestrian level crossings.

The next location of interest is Haywards Junction. This name signifies the location where the new double track line and the old single track line to Silverstream crossed over. Whether there was actually a connection like a set of points is unclear. There may have been a connection at the Silverstream end as this part was used as a siding for some years and in fact was where the Fell engines were put in for scrapping. If this was the case it seems odd there would need to be connections at both ends over such a short section. The main value would have been if Railways had built the new bridge themselves and used their own track mounted cranes from both ends at once.

"Haywards Junction" showing the difference in routes between the original single track and the present day double track.

The old Silverstream Bridge showing how the double track embankment cuts through the single track route. This made a junction at "Haywards Junction" as shown in the previous map unlikely unless "Haywards Junction was actually at the point shown above. Note I am relying on the Quail Atlas's suggestion that Haywards Junction was actually this location and not back at Haywards where the eastern and western lines joined. Silverstream Bridge actually had two separate wooden bridges in different eras, upper quadrant signals at the west end, and a ballast pit.

The original railway between Haywards Junction and Silverstream was closed in November 1954 with the opening of the double track deviation to the north. It was then abandoned until 1977 when the Silver Stream Railway heritage group moved in to establish there. The bridge had been demolished soon after closure, so the part available which is operated today consists of the formation from the east side of the bridge up to Silverstream station. 

The SSR has a main entrance off Reynolds Bach Drive near the old bridge and their main depot is located there. The old 1536/1537 signals gantry and signals have been replicated on the heritage site.

The Silver Stream Railway took a few years to be developed but in 1984 they were ready to move their rolling stock into their site by temporarily connecting to the NZR network at the new Silverstream station. They had to lay a few hundred metres of track and bridge a stream to make this happen. After the move was completed the temporary track was all taken up as there is no permanent or semi-permanent connection to the site (unlike the situation at Ferrymead where the connecting track was left in place and used a number of times over a period of years until the eventual permanent switchlock was installed).

 1941 view of Silverstream across the single track station in its original location.
 1984 with the temporary connection to the SSR site going in.
2017, the "North End" of the SSR has been developed with several rolling stock sheds, one of which is used by NZRLS for their ex-WMR carriages.

Saturday, 14 July 2018

Otago Central Railway [63L]: Ranfurly-Alexandra 12 (Lauder-Auripo 1)

Here we have a 1951 diagram of Auripo. It looks like the proposed extension of the loop was constructed.

Auripo was one of the smallest and most remote stations on the Otago Central branch. It had just a small shelter, loading bank, one loop and a stockyards. There were no extra sidings or goods shed so it was very minimally equipped. There was a small rural population in the general area but the nearest township was some distance away.

I can't publish this actual diagram in the official maps without ANZ permission which I can't be bothered getting, so the reason for having this diagram is just to check positions of key structures and the track.

I have a few plans of Auripo but there isn't really any more detail than is in this plan. But the aerial photography I had hoped would be available hasn't come online yet, so I don't expect to be able to show anything better than the low res 1976 stuff I have been working with up till now.

Friday, 13 July 2018

Wairarapa Line [4]: Hutt Valley Line 2

So now I have the complete set of aerial coverage for the Hutt Valley route here are some samples showing what these locations looked like in 1939/41.

Whilst continuing with some stuff around the Wellington area I need to shift my focus back to the South Island so there won't be much more along this theme for a while except for completing the Johnsonville-Tawa stuff in the next few days.

Wednesday, 11 July 2018

Wairarapa Line [3]: Hutt Valley line

Well we have been relatively quiet over the past week as I have thrown a lot of resources into the Hutt Valley line, which looked very different in 1939. The line was opened to Waterloo in 1927, but was not further extended to Haywards until the mid 1950s, when it took over as the main line, with the line via Lower Hutt and Melling closed beyond the latter station. This means that the route between Waterloo and Haywards was just an empty corridor, and I have been busy creating mosaics for that section over the past few days and generating tiles to go in the maps.

Waterloo seen in 1939. The original island platform is visible albeit with track only one side of it, and an overbridge access. The subways seem not to have been provided at this time.
Waterloo in its present form. It was rebuilt in 1988 as a transport exchange for the area and this entailed re-adapting the island platform to its original format with track only on one side (Down Main) and another single sided platform for the Up Main. The subway on the south side still exists but it appears the one on the north side, which can be seen in a 1960 aerial photo, may have been filled in, or else there is access to it from within the station these days instead of externally. Subways do not appear to have been installed in 1927 as an overbridge was provided for passenger access off the north side.

Friday, 6 July 2018

Wairarapa Line [2]: Gracefield Branch 2

Well the last couple of days have been work in downloading the aerial photography needed to do the Gracefield Branch. This is split up into three sections: Woburn station, Hutt Park station and Gracefield station.

At the moment I have completed a mosaic for Hutt Park and am working on the mosaics for Woburn and Gracefield. Normally when creating a mosaic you have to overlap to the adjacent mosaics on all sides in order to ensure the tiles all line up properly when you bring them into the GIS. So I have to create a part of Woburn using the aerial imagery that is then used to overlap onto the Hutt Park aerial imagery, which in its turn overlaps onto the Gracefield aerial imagery. Hence the Gimp project has started with a large grid of 28 LDS tiles (4x7) covering the entire section from Woburn to Gracefield, which has now been split into three pieces. The Woburn piece will be further expanded with extra tiles and imagery because it only covers a part of the station, just the part that was in the first aerial image, which has been cropped to the edge of the tile boundary between Woburn and Hutt Park. The Hutt Park piece will be used to align the Gracefield imagery before it gets cut up into Hutt Park and Gracefield tile sections.

The mosaic for Hutt Park has now been extended with 1978 coverage which was such a high resolution that two images are needed to cover the area. The full set of images for 1939, 1978 and 2017 are below.


Wednesday, 4 July 2018

Wairarapa Line [1]: Gracefield Branch 1

Since I did a bit of Wellington station last month I have shifted my interest to Lower Hutt and various areas to be covered there. One of the first will be the Gracefield Branch and Hutt Workshops and right now I am downloading background aerial photography at high resolution of Lower Hutt and Upper Hutt (and also Porirua City for the NIMT). 

Here are a couple of aerial shots of interest in the Lower Hutt area.

Lower Hutt railway station as seen in 1939. The line that passed this station was then the main line from Wellington to Woodville over the Rimutaka Incline. In the lower right corner of this photo the "Hutt Valley" line branching at Petone can be seen as it approaches Ava station. At the time, Waterloo was the terminus of this "branch". The Hutt Valley branch eventually became the main line and the Lower Hutt route was terminated at Melling and has since then only been used by suburban electric units.

Hutt Workshops, also in 1938. The Shops is still a large site although some buildings have been knocked down and small parts of the site converted to residential or commercial subdivisions. The Gracefield Branch now only runs as far as the workshops, Gracefield having closed around 2000.

Otago Central Railway [63K]: Ranfurly-Alexandra 11 (Omakau-Lauder 4)

Here are the final maps for Lauder. Aerial photography alignment was pretty difficult for this set of maps and what you can see reflects the best outcome I could achieve.

The maps use the newest style that I am rolling out across all different map types for making them easier to use.

Next station down the line is Auripo.

Handheld Navigation

Last week I touched on the subject of how to use the maps "in the field" and the challenges faced.

Here is a map from the volume of the Napier-Gisborne line. I travelled from Wellington to Gisborne on the 22nd of June and returned to Wellington on the 24th.

From there with a bit of quick work we have got to this type of map as a picture.

Our trip out of Wellington happened to take us along this very route via SH1 which reuses the former NIMT rail corridor from Johnsonville to Tawa. 

Essentially on a handheld device you have to lock the rotation because when the map doesn't orientate exactly to the direction you are going in, you have to physically rotate the tablet to suit.

The main improvements are:
  • Creating the maps in a Google photo album. Actually this has always been the way I intended to distribute the maps, but many of them have not been published yet. So I plan to move ahead and quickly republish many of the partly completed ones in the new layout shown above.
  • Downloading the Google photo album to a handheld device lets you use it offline, outside a coverage area, or if you haven't got a lot of cellular data. 
  • Putting the navigational markers on the top of each map. This lets you know which direction to swipe in to get the next map for the direction you are travelling in.
Generally I would recommend if you are travelling by road you will probably want a second set of maps of some sort for keeping on the right road. Whilst I publish roads and other landmarks on the map as much as I can, it's impractical to show all the roads where they aren't close to a railway so road navigation is not what the maps are best at.

Tuesday, 3 July 2018

PNGL Maps Update {2A]

Following on from the last post I have updated one of the images in the collection (the one that covers Ormondville). The address again (this time spelt out for those reading this post syndicated to FB):

Basically I have added two points to every font size on the map. The result is much more readable than the earlier ones. The nav labels and arrows have also been improved.

I think within reason this is an acceptable compromise for handheld devices, a phone is still not going to be optimum but it is too difficult to cover every single base, as the font sizes are set in the map project, not in the layout template, so they are global for every single map that is produced from that project. If I wanted to vary font sizes I would either have to have a different project, or use the scale based font sizing which is an interesting feature I haven't really looked at before, and which could still be a little tricky to set up.

Monday, 2 July 2018

PNGL Maps Update [2]

The first set of samples for handheld navigation have been produced for testing. I have tested these with a phone (Nexus 5X) and with a 8" Samsung Galaxy Tab A tablet.

The collection for Volume 5 is located here

Here is the first of the maps in the collection.

Whilst the maps look good on a desktop it is different on the small screen of a handheld device. On the Galaxy Tab A (8") the text was a little small but still readable.

On the Nexus 5X phone the text was really too small to read easily and the top and bottom borders were masked out by the status bar and navigation bar for the phone.

It's not easy to cover all bases with the map templates. The intention with these diagrams has been to have them usable for a computer screen rather than a small handheld device. I will have a play to see if the text size can be bumped up a couple of points without having too much impact on the layout, so that the text is easier to read on a handheld device.

The navigational labels give a good indication of which way to swipe but the text needs to be more visible (darker) than the grey seen above. The arrows are OK but perhaps they should also be darker.

Overall I would think these diagrams will be straightforward to use for field navigation with a few tweaks and more testing will be undertaken in the coming weeks before spitting out a full set of PNGL diagrams.

Saturday, 30 June 2018

Otago Central Railway [63J]: Ranfurly-Alexandra 10 (Omakau-Lauder 3)

Due to being busy with a few other things there hasn't been much done on the Otago Central rail maps lately. I'm working on Lauder again but the mosaic still needs some work before I can actually use it. The interim version of Lauder is below.

As you can see there is improved image quality in this 1965 aerial photo which has been the main goal of reworking the aerial mosaics.

But as I noted above this mosaic has to be done again because of misalignment of the tracks. There is always going to be some kind of alignment issue because of the inherent nature of aerial photography, but the tracks on the ground have to line up, because flat features on the ground over a short distance with minimal altitude change are the least affected by variances in un-orthorectified imagery, and so it's reasonable to use these features as the alignment baseline.

As a result I need a few hours (probably early next week) to correct the mosaic and then bring in new map tiles to the GIS, realign the map features, and then produce the final versions of the maps. So there will be one more post about Lauder when those maps are completed.

And then the next station to be looked at is Auripo. It will be interesting to see if LGGA have scanned the only available survey of a good resolution, Survey 112, yet. If they haven't, I have some ANZ track diagrams I can put into a mosaic to trace off, and then some other low resolution aerials to use in the mosaics for the final maps.

Thursday, 28 June 2018

PNGL Maps Update

As I have mentioned on other posts recently I am working towards re-issuing the existing map diagrams for a number of areas where they were available in the past, but have not been online since changing over to Google Photos as a display system.One of the map sections which I am looking to re-issue in the near future is the Palmerston North Gisborne Line. Since part of the closed section is being re-opened it is time to update the maps for Napier-Wairoa. There was a published part volume for the Napier-Gisborne section which is not being updated or republished at this stage, since volumes like this are part of the full production process that incorporates the overall revision of map data using aerial photography, and there is no immediate timetable for the total revision of the Volume 5 content or the publication of rail maps for the section.

So there will soon be a new set of map diagrams for the entire PNGL using the updated template mentioned in the previous posts and designed to facilitate being downloaded and used offline with an electronic device such as when used in the field.

The map project for the PNGL beyond 82 km, which is the boundary between Wairarapa and Hawkes Bay, is being updated to the latest data standards. All of the map data shapefiles have been converted into the new GeoPackage data format. All of the terrain GeoTiffs have been reprojected as EPSG:3857 so that there is no need to have on the fly reprojection of any older EPSG:4326 layers. The data tables for all relevant layers are having the generational fields (yearIns, yearDel) and other useful fields (comment, customFlag) added to them as has been already undertaken with most of the other map projects to date. The layout template for 16:9 format maps will be updated to add the navigational markers for use when swiping between maps on an electronic device as mentioned previously.

Expect to see some output either from this project or some other aspect of maps in the next few days but things have slowed down in the last week or two due to family matters and other considerations.

Tuesday, 26 June 2018

Map production update

People who have been following this project for a while know that we did issue map collections for a considerable portion of New Zealand when we were using Flickr to store these collections. As a result of the reorganisation of NZ Rail Maps resources when the website was set up, the Flickr collections were taken down and replaced by Google Photos albums.

Since that was carried out, the previously generated map collections have, for the greater part, not been republished in Google Photos to date. We are now planning to re-issue the previous maps (diagrams as we now call them) for as many lines as they are currently completed for. These will be published to the latest template standard but the map data in them will be largely unchanged. However where addition of new data has been partly completed a decision will be made on whether to republish as is or complete the addition of new data before republishing.

The current project for updating the maps is largely focused in two areas:
  • Tracing over current Linz aerial photography, and using that as a map background
  • Adding additional content to the maps from historical aerial photos and using these photos as map background.
This work will be ongoing. The first step is relatively straightforward in mapping but does require significant preparation in downloading and selecting the aerial photos needed as a background for a particular volume of map production. The second step is more time consuming as georeferenced mosaics have to be created for a particular location of a route (such as a station, yard or depot) and then traced over with the additional detail added in a way that makes it possible to publish multi generational maps for the specific location. Hence the update aspect of the project is slower in terms of the publishing of content.

Map volumes will be published for each volume as the aerial photo based maps are completed for the entire volume. There are twelve volumes whose content is listed on the home page of our website. Some of these volumes have been published over the last four years, mostly as diagrams. The Nelson volume which has been published more recently uses aerial photo backgrounds as an experiment. 

There are two main types of published content for the maps. These are:
  • Rail Maps - these show the map data published over a background of current and historical aerial photography. They are most suitable for use with electronic devices where the full colour of the aerial photographs can be viewed without limitations.
  • Map Diagrams - these show the map data with a plain white background. Diagrams are ideal for use where there is a need to have a physical format such as by printing individual maps that are downloaded off the web or by printing out one of the map volumes that are produced for a particular group of routes.
As noted above we have experimented with using both formats in map volumes. However, the intention when producing map volumes has historically been geared towards a printed solution for those users that wish to have a physical variant of the maps. The aerial photo background used in the recent Nelson volume is really only of use when viewing it on an electronic device and the volume format in a PDF file is sub-optimal for field navigation because of the layout of individual pages that frequently contain multiple maps for efficient use of space. The use of colour content in the maps is also contrarian to easy and cheap printing as the colours will not always reproduce well in black and white printing or copying, and colour printing is often too expensive for many people. Hence, we expect that map volumes produced in future will all be based on diagrams.

Rail maps are currently published using Google Photos. We have discovered that it is possible to download a complete Google Photos album as a zip file to a device. For field use, this is the optimal solution and the photos in each album will be named in a numerical series that makes it easy for them to be browsed using a picture viewer that relies on alphanumeric sorting of the images. As previously described in the last post about field testing, the banner that has been added to the top of the more recently produced maps will have directional labels added to it to make it easier to navigate with a collection of maps on an electronic device, whether online or offline.

Monday, 25 June 2018

Field testing maps

This week we've had a bit of a field test of the maps just to evaluate some of the different ways they potentially could be used. Having been both on and off net over the course of a 2000 km trip, and travelling by road most of the time, we've had a bit of a think about some of the practical aspects of using maps.

These days with electronic handheld devices, one of which is being used to write this post, there is a great deal of inbuilt adaptability and convenience. Online platforms have transformed navigation for travel, but require a large and expensive web based infrastructure to provide the user interface for the platform. 

This project works on the assumption that people can still print maps out onto paper and carry a physical volume or medium along with them. As we all know the online platforms have little usefulness when out of mobile coverage areas, as is the case in significant areas of New Zealand.

Whilst retaining the focus on a format that is designed with physical media in mind, some effort will be expended on seeing if we can find ways to make the maps easier to use on a handheld device such as a tablet. The main issue is making the switching from page to page easy and intuitive to the greatest possible extent, given that rotation of a physical device is possible to orient the map the correct way up - just as with a physical map - and that there is then a desirability to have indications of which way to swipe between pages.

Tuesday, 19 June 2018

North Island Main Trunk [5]: Wellington Station 2

These three views are the same area of Wellington station yard. From 1900, 1938 and 2014. The turntable nearer Thorndon Quay was the one used by the WMR at its depot site.

Monday, 18 June 2018

Otago Central Railway [63I]: Ranfurly-Alexandra 9 (Omakau-Lauder 2)

As I wrote in my last post I am currently updating the map of Lauder station. 

These two images are respectively 1938 and 1965 images of Lauder. There is no apparent change in the layout of Lauder between these two periods.

At this stage there are no plans to extend the masking as I am unaware of any additional area that would benefit from being displayed in a part tile export.

The main improvement in this map will be the sharper 1965 aerial imagery due to having reduced the number of transform steps to the historical layer to one.

Saturday, 16 June 2018

North Island Main Trunk [4]: Wellington Station History

While I am at this very moment creating the map tiles (and will have them finished tonight) for the Tawa end of Johnsonville-Tawa, here is some detail of the history of Wellington Station as depicted on a map. (The tiles for J-T at the Tawa end have taken longer to create not because of the usual size problems with the mosaic, but because of having to work around a bug that crashed Gimp repeatedly until I figured out how to work around it. This lost me about a day. By contrast when it has taken so many hours to export tiles out of the mosaic, this part is proceeding extremely quickly, so much so that the tiles will be finished in a matter of hours rather than days. I may even be able to reconsider having to have a computer with 32 GB of RAM to process the mosaics because 16 GB may prove to be sufficient. I have to do some more testing to try to determine exactly where the resource constraint issues are occurring in Gimp because it seems that is the issue, not the images I am working with.

So WCC has on the Koordinates website some maps of Wellington Central from 1900 made by someone called Thomas Ward and they have a lot of detail about what Wellington used to look like because they have the tracks and structures in the old Wellington railway yard. So this has given me the detail I needed to place the old Thorndon and Lambton railway stations as well as some other detail that will be drawn into the maps in due course as I work my way through the current and historic layouts of the yard.

Here are some renders from the current and historic imagery of Wellington railway yards.

The main part of the modern passenger station and the historic Lambton station which was the NZR passenger station for trains going through the Wairarapa and over the Rimutaka Incline to join the NIMT such as it then was at Palmerston North (prior to 1908). Lambton ceased to exist after the new Wellington station opened in 1937 and this was at the same time as the Tawa Flat deviation came into operation bypassing the old WMR / NIMT line over the hills via Johnsonville.

The main line (NIMT) heading north out of Wellington in 1900 (it was still the WMR then) took quite a different route from the main lines now. Part of the reason for this was that the WMR had its own railway yards which the NZR main line had to clear.

WMR had its own separate station called Thorndon for their trains and after this was taken over by the government the station was used for trains on the NIMT via Johnsonville. The 1900 maps don't show the full layout of the WMR yards so I won't at this time be able to add the full detail, however aerial photos of Wellington yard from 1938 should make it possible to show some of the detail but this of course is post-WMR and as such the yard at that time was not a separate operation. Thorndon Esplanade as a roadway is interesting as it has all disappeared today under the railway and Aotea Quay.

The last two maps show how the main line as it then was headed north out of Wellington. I have had to trace the route shown on the last map and therefore have to assume for now that there really was that incredibly sharp curve just past what is now the motorway bridge to meet the existing alignment of the Johnsonville Branch as this was the WMR/NIMT.