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Category: NZ Tekonverse -> NZ Rail Maps Technical

DreamHost vs GoDaddy vs local… webhost pros and cons

Well this time around I am going to write about the choice of webhost platform. Web hosting these days can be a lot cheaper than it might have been in the past as there is a lot of competition. In New Zealand you can get quite reasonable web hosting with 150 GB of disk space…

2020-12-11
NZ Rail Maps: Using Gimp To Georeference Retrolens Aerial Photos [7]: Extracting Mosaic Tiles

So I have been trialling the alternative overlay method with more files and have decided to redo all the mosaics for Auckland so far. This is a few days’ work but as there are already some issues with accuracy in some of the more hilly areas or where the embankment is raised, it is going…

2020-06-02
NZ Rail Maps: Using Gimp To Georeference Retrolens Aerial Photos [6]: Alternate Overlaying Technique

Today I am going to look at an alternative way of stitching together the source layers. I have to do a set of mosaics for the station of Kamo, which is the northernmost part of Whangarei. From a rail perspective there were two stations there. Just a little south of Kamo there was a coal…

2020-05-25
NZ Rail Maps: Using Gimp To Georeference Retrolens Aerial Photos [5]: Overlaying Multiple Layers

So in my last post I showed how to get started in georeferencing with the first overlay. In that post I put the second layer in to show how it would join onto the first layer. The aim of this part is to show how to add additional overlays and how to deal with the…

2020-05-24
NZ Rail Maps: Using Gimp To Georeference Retrolens Aerial Photos [4]: Getting Started With Overlaying

So now we can look at how we actually do the georeferencing. This happens as a multi part process, and explaining the steps gives you an understanding of how it all works. The basic of georeferencing a historic aerial photo, is that by aligning it to a current aerial photo, of which we know the…

2020-05-24