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Some Very Cool Data

This post reviews LiDAR data available for the southern continent and the Dry Valleys in particular. From the raw data we derive a high resolution DEM. I hate to say this, but some data are cooler than others (Ed. What a geeky thing to say…) and LiDAR data certainly fit into that category. We’ve talked about LiDAR earlier –…

Save your marriage – use layer files

Layer files are a useful way to recreate legends and get consistent symbology. This post outlines what they are and how to use them. Geology…who doesn’t love geology? And who doesn’t love geology maps especially? (Ed. – Only heathens…) The image below shows one of the 1:250,000 scale geology maps that cover the country, produced…

Another Point on the Map (Part 3)

Quality assurance is crucial when creating new data, especially with geocoding. We cover some of the frustrations of this process and some useful tips (definition queries and label scale ranges) to make it a bit easier. I can safely say that over the past few days I have been almost everywhere in New Zealand: from…

A Humble Table Join Saves the Day

Table joins are an easy and convenient way to link data in spreadsheeets to spatial layers. Here we cover a good example of one simple table join deciphering some codes in a soils layer. Those familiar with the J: drive will know that we hold many national scale datasets, from soils to land use to…

Finding Yourself in Bali

The Balinese have a unique way of locating themselves. “North” is not always “up”, unless it’s uphill to the volcano. My daughters tell me that I’m at risk of flexing here, but bear with me. We were lucky enough to spend some time in Bali recently and while there are heaps of things I’d love…

An ArcGlobe Tutorial

In this post we look at how to use ArcGlobe for 3D visualisations of large areas. One benefit of using GIS is the creation of 3D visualisations using geographic data. Often we can use ArcScene to do this, but it doesn’t take long to butt up against its limitations (speed, quality of display, fiddle-iness…), so…

Tired of those boxy maps?

In this post we look at alternative shapes for data frames to create more professional maps. It was with great pleasure that I learned how to do something new with ArcMap the other day. It’s increasingly impossible to know everything there is to know about GIS so knowing how to do new things is always…

Flow Diagrams That Work

We cover executable flow diagrams using ModelBuilder in this post. In a previous post we covered a straightforward example of a quick GIS job that involved Merging and Dissolving 43 input contour shapefiles, then selecting and exporting a subset. At the end, I flippantly included a flow diagram, reproduced by the magic of science below:…

An Embarrassment of Contours

This post discusses how a large collection of contour shapefiles were merged together, dissolved and then a subset of contours were selected and exported. Here’s an example of a relatively quick and easy GIS job that frequently comes across my desktop. Woody from SOLA contacted me with a question about some data he had. It…

Where This Is No Elevation

This post covers how elevations for dragonfly observation points data for Vanuatu were sourced from a space shuttle mission in 2000. For creatures that weigh way less than a gram, dragonflies have certainly kept me busy over the years. We’ve already seen how my colleague, Milen, used some offline maps on his phone to collect…