Monday, 21 May 2018

MSL Lyttelton-Rolleston [5]: Christchurch Station 5

So this has been a lot of work but I now have usable aerial photos of Christchurch, Linwood and Opawa. As I noted previously I chose to extend the limit of the previously drawn maps from Wilsons Road out to the Opawa bridge. This means the total length covered is from just under 9 km, to 11.75 km - a total of nearly 4 km. All the tiles have been rendered (a total of 29, which is a lot considering how long it takes the computer to generate each one), but one needs the mask to be altered and then re-rendered, and I'm looking to add several more around the edges.

With all this work the Otago Central maps have had to wait except for one post about Galloway. Now that I have the Christchurch maps I will be working on them at the same time as carrying on with the Central and working up to the next station at Chatto Creek which shouldn't be a lot of work, and then further onward. In fact this section of the Central maps shouldn't take long to do.

Here is some of the Christchurch stuff that hasn't been published so far.

Waltham Bridge (as it was in 1970), part of the gasworks, E shed and the freight sidings.
The car depot building and carriage sidings. With the demise of many passenger services the sidings to the right made way for the Daily Freightways shed, which is now occupied by Southern Demolition.
Linwood station and part of Loco. The station was removed when passenger trains to Lyttelton ceased, not too many years later.
The main Loco buildings adjacent to Ensors Road crossing.
Opawa station and the bridge. There was a footbridge alongside the railway structure for easy access to the station. This is another passenger-only station that is long gone, and the building through of Brougham St (1990s?) has altered the landscape significantly since then.

Saturday, 19 May 2018

MSL Lyttelton-Rolleston [4]: Christchurch Station 4

So I have finally completed the aerial mosaics that will now cover from the western station limits of Christchurch all the way to Opawa. As usual it has just proved easier to add the images for Linwood and Opawa to the Christchurch ones and so these extra steps have been completed along with Christchurch/Waltham.

In along with that I installed the new version of Gimp (2.10) and one of its features is the unified transform tool which makes it possible to combine the scale and rotation steps. In short, it is much easier to use than the scale tool because you can deform the image as well, which means in effect you can pretty well drag it to the exact proportions you need. I have been using a development edition of Gimp (2.9.7) for some time and this release of 2.10 improves on some issues as it is a production version of the software. 

Here is the Gimp mosaic for Christchurch West-Linwood-Opawa which will now be split into several pieces to allow the production of the map tiles needed to be loaded into Qgis. Mapping will then resume. 


Wednesday, 16 May 2018

MSL Lyttelton-Rolleston [3]: Christchurch Station 3

The past few days have been busy, however I have made a reasonable amount of progress and these images reflect that. I expect to have the mosaic map tiles for the entire area of Christchurch ready by the end of this week. Here are samples.

Right now I just need to add one more aerial photo to complete Christchurch Station and hopefully that one will also cover Linwood at the same time.