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Saturday, 18 April 2015

Creating an 'Atlas' using ArcGIS and QGIS

Usually when I produce maps, I produce a single map based on single theme. However, back in my uni days and work training, I have learnt an important cartographic component in ArcGIS and QGIS.

A sample Local Government Area map of New South
Wales built on ArcGIS
It was about building an 'Atlas' in GIS. Multiple maps stored in one PDF and ready for print. This knowledge was put to the test when one of my Account Manager said he wants a map of all his clients (October 2014). His clients are spread over one state and he had a list of them in Excel. Good thing was they were Local Governments only.

In April 2015, another Account Manager approached me and asked me to produce a map of local governments and water authorities in New South Wales. You may think why do we need an Atlas style product for these two instances?

In this discussion, I will be discussing the challenges behind making these two 'atlases' and some comparisons between QGIS and ArcGIS.

Challenges/Issues to Consider 

  • Data - In Australia, they have free data for Local Government Areas. However, the free data they had for the road network and localities are nearly 10 years old (Sourced from Geoscience Australia).
  • Intended Audience - Account Managers use these maps as rough guides where their clients and prospective ones are found. Sometimes they may use for rough planning when they traveling around to see multiple clients. Hence, just showing the local government areas (LGAs) is not enough. I cannot expect my audience to know every LGA by name and location. Due to that, I incorporated roads and localities to give good geographical insight
  • Level of Information Displayed - This becomes an issue on how many towns and cities the map should contain. If you refer to the first figure above, I classified the localities strictly to towns and cities. My Account Managers doesn't need to know every town or populated area in LGA. They need to know LGA name, the main town (s) and some roads connecting between towns.
  • Scale - The most difficult issue I faced. New South Wales has over hundred LGAs of varying size and it is impossible to have clean map with all names of LGA. That is why the concept of mapbook was used in these two instances. ArcGIS and QGIS uses one shapefile to break down the mapbook into regions. I used Tourist Regions to divide the various states in Australia to produce multiple maps. However, in the context of New South Wales, I felt Tourist Region is very general division. I chose Statistical regional divisions to show more zoomed-in views of Sydney area. Sydney has many smaller size (only area we talking about) LGAs. 
  • Text Layout - Text is necessary evil. I have ZERO intention of using any other graphic software to beautify the map. I am producing the map on the go and would like to deliver fast to my Account Managers. I fully capitalized Maplex Label Engine (in ArcGIS) to position text at best. 
  • Software - I have used mapbook approach twice (in real life situation) so far in my cartographic career. The first instance, I was motivated to use QGIS to produce mapbooks for many states. The second instance, I used ArcGIS as I have not used Data-Driven pages before.Both instances they were learning curves for me.

ArcGIS/QGIS

I was very much grounded to ArcGIS (the only GIS software I knew at university). I came to know QGIS through my current work and learned further through QGIS training. Some opinions:
  • In both GIS software, the final layout and content to be displayed are nearly the same. You can change the paper size, adjust the legends and placing inset maps in ArcGIS and QGIS
  • From my experience, time consumed from the collecting data to final output are nearly the same for both software.
  • However, the KEY difference between ArcGIS and QGIS I have noticed is the cartographic presentation. In ArcGIS, they have more in-built colour schemes than QGIS. Hence, I spend less time in determining on one of the fundamentals of maps. In text labeling, I was pleased both in performance by ArcGIS and QGIS
If you ask my stance, I tilt to ArcGIS due to my longer exposure comparatively to QGIS. However, the essence of this blog post is not about which software is better than other. In these two instances which used two different software, it is principles of mapping that played a big factor:
  • Who is my Audience?
  • How much information my Audience needs to see?
  • Is the datasets needed for the map readily available?
  • What scale level should I utilize? Should it be fixed or dynamic
  • What is the best position for the labels
  • Is the overall map layout conveys the right information the Audience needs to know?
Resources I used for building the map books using QGIS and ArcGIS

Atlas Generation in QGIS  and map book in ArcGIS: 
















3 comments:

  1. great comparison, nice n honest.. great to see QGIS is holding its own.. currently a stay at home parent with loads of experience in ArcMap, but only access to QGIS now I'm off the grid. I'm with you, dont go to a second piece of software when the GIS most often has so much potential we havent even tapped into yet, or dont expect them to have. I'm off to have a play with QGIS again.. thanks for the motivation

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  2. Melissa, I just want to clarify that in this context, there was no need to use graphics software. The maps were meant for non-artistic or grand purposes. I produce maps using ArcGIS and use Adobe Illustrator to beautify. I agree with you fully that GIS has so much untapped potential - I only know some and tend to use GIS for cartographic purposes. The rest is an unknown world.

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    1. absolutely, I firmly believe that we should work with the final product in mind, and that there is rarely one 'right' route to that end. ArcGIS and AI/PS work wonderfully together especially creating custom scalable vector point symbols etc via EMF.., but I'm now venturing into the possibly equally as stunning partnership of QGIS and Inkscape/GIMP !

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