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OCAD & Mapping Snippets

1915 Vic Geo Survey Dunolly map extract

OCAD reminders

Some tips that tend to be overlooked.lightbulb

40%, 20% discounts ending

And another tip – the big discounts for updating OCAD 12 or 11 to 2018 finish at the end of next month. If you have been thinking about it, I suggest you either do it or diary it.

Team OCAD edition image4 clubs benefit from Team licences

Four clubs have taken advantage of the opportunity to acquire Team licences. In three of those clubs, some club members transferred their licences to the club. Then the club traded each licence in for two Team licences.

Massive savings, significant flexibility. Check out my recent post Hidden Value in OCAD Team Editions for more info.

GIS file conversions

A conversation that crops up more frequently in the lidar era is how to convert a file from one format to another. The FME Integrations Gallery may have the answer for you.

Conversion categories include CAD, GIS & Mapping, Lidar & Point Clouds. The Cloud version appears reasonably priced for say a state orienteering organisation. There is also possibilities for free versions.

Open source PDFsamDocument

Frustrated at the limitations of Adobe Reader and can’t justify Adobe Acrobat? Then take a look at the open source PDFsam.

PDFsam Basic is free and enables split, merge, extract pages, rotate and mix PDF files.  PDFsam Enhanced comes in 3 flavours giving you even more options at a reasonable price.

QuestaBird

Your kids looking for something more to do while waiting for you to finish the course? Or vice versa? QuestaBird is a mobile based adventure game with a purpose. Use your phone to photograph birds, butterflies and moths,  competing with others to collect the most species and the greatest number of animals in your area.

“Players are not only learning about their environment, they’re collecting data that helps protect it.  In effect they have become citizen scientists without even knowing it.”

Andrew Robinson, co-founder of QuestaGame

Downunder geospatial awareness ratingsgeospatial

Australia is ranked 14th and New Zealand 25th in terms of geospatial industry awareness according to Geospatial Media & Communications.

Criteria are data infrastructure, policy framework, institutional capacity, user adoption levels, industry fabric (whatever that means).

The top 10 starts with USA, and apart from Singapore, China and Canada, comprises European countries.

Your dream mapping career?

If you ski you might have seen his work. Jim Niehues, The Man Behind The Map.


The featured image is a very small segment of the 1915 Victorian Geological Survey County of Gladstone map. The detail, drawing and printing is of the highest quality but unfortunately does not show up on this image.

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A Bit of Latitude Crept into the Datum

Geostationary Satellites

Australia and New Zealand Datums

Thanks to our active tectonic plates, the datums of both countries are becoming rather outdatumed. For example, Australia has had about 1.5m of land mass shift from its 1994 position relative to the earth’s surface.

NZ has implemented its new datum NZGD2000 and projection NZTM2000.

On 1 January 2017, Australia’s first step in a multi-year process is heralded by implementation of GDA2020.  The second stage is in 2023.

In Switzerland we are changing too from CH1903 to LV1995. So the reference system in Switzerland we are using is more than 100 years old and it takes more than 20 years from the new measurement to changing to the new reference system. — from Gian-Reto at OCAD Inc.

Background

The latest Australian official advice re the datum changes is on the ANZLIC Committee on Surveying and Mapping website for GDA2020

Also worth reading is this presentation from RMIT.

NZ Map Grid

For New Zealand datum change see the NZ Land Information website for NZGD2000

OCAD Co-ordinate Systems

The OCAD co-ordinate system combines datum with the country map grid. e.g. GDA94 Zone 55.

OCAD Inc already has in place the new NZ co-ordinate system based on NZGD2000.

When the Australian parameters are available, they will do the same for GDA2020.

Transforming from Old to New

Very simple. Under the Map | Transform menu you select Change Co-ordinate System, then select the new co-ordinate system and it is done.


Geostationary satellite image source Wikipedia

Not entirely unrelated

GPS registers most accurate signal yet. NASA aerospace analysts recently calculated the signal-in-space accuracy of GPS to 38 centimeters. Good news for farmers and auto-drive car developers. Read more and also click the image at top of that reading for GPS info you might not be aware of.

 

 

 

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ELVIS LiDAR data mapped via OCAD

ELVIS LiDAR and OCAD

The ELVIS output format Esri Ascii Grid, can be imported directly into OCAD 12 via the Import Wizard in the DEM menu. So you not only have an easy way of obtaining the data, you also have an easy way of using it. (See my earlier post ELVIS rocks with LiDAR contours on the basics of using ELVIS).

ELVIS LiDAR vs state geospatial vector contours

For a small area of Anglesea used in 2015 for a mountain bike orienteering event, I downloaded ELVIS LiDAR and VicMap vector contours. Then overlaid them in OCAD.

The brown contours are VicMap 10m obtained via download of vector form via Shape file.  25m index contours were also obtained but do not appear in this fragment.

The other 3 colours are from ELVIS LiDAR data;

  • grey is 1m (shown only in second image)
  • green is 5m
  • purple is 25m index contour

At first glance there is a general consistency if we ignore the many minor indentations in the LiDAR lines that could be easily smoothed in OCAD.

LiDAR 5m VicMap overlay

However the 1m LiDAR does indicate the existence of two lower parts of gullies that are shown in the VicMap contours, albeit the eastern displaced. So maybe 1m contours could usefully inform the mapper at draft stage in some map areas.ELVIS LiDAR vs VicMap vector

LiDAR contours smoothed via Karttapullauten

Karttapullauten generates orienteering training maps from LiDAR data.

This is similar to the result when smoothing in OCAD except that Karttapullauten has interpolated 2.5m contours (the dashed lines). Interestingly, this makes the progression of the above mentioned eastern gully much easier to observe.

LiDAR data smoothed in Karttapullauten

Using ELVIS DEM data in OCAD

There are 4 video tutorials on DEM at http://ocad.com/en/support/learn-video. These videos are useful for OCAD 10, 11 and 12 users.

I created a 4 minute video tutorial on the basics of using ELVIS. View it online at www.screencast.com/t/y3MTbMzzO

Following on from that is a  4 minute video showing the import of ELVIS DEM into OCAD via the DEM import wizard. (This is applicable for any DEM data). View it online at www.screencast.com/t/qBqaZrmu

Users of OCAD 10 and 11 don’t have the wizard but should be able to interpret the wizard settings.

And here is an OCAD template file I created to import the DEM data and then in turn it is imported into your OCAD map file with minimal symbology and colours.

TIPS

  1. When you download ELVIS data, it is the .asc file that OCAD DEM import wants,not the Shape file.
  2. If you get nothing showing after import, then check the .asc file content. You can use any text editor to read it. In the header lines there is a value for NODATA. If the file is composed completely of that value then there is no LiDAR data for the area you selected. ELVIS now warns you if there is no data in the selected area.
  3. When you are asked which co-ordinate set you wish to use, unless you have set up your OCAD file to match the location of the imported DEM data, then select the upper set which is that of the DEM data. Else the DEM data will likely be located far beyond the reach of your OCAD map area.
  4. If you expect to frequently use LiDAR data, then importing into a special OCAD file can be a boon, It should be empty and have just essential symbols that don’t clash with standard symbols for when you import that OCAD file into your working file. Such a template is downloadable from the section immediately above.
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ELVIS rocks with LiDAR contours

image Elvis storm 1998

ELVIS delivers 1m, 5m, 25m contours – free!

ELVIS is Geoscience Australia’s new elevation information system. It is free, licenced under Creative Commons and makes public LiDAR data very accessible. Thank you to Russell Rigby, mapping convenor ONSW who made me aware of ELVIS. The LiDAR data available is;

  • SRTM-derived 1 Second Digital Elevation Models Version 1.0
  • DEM SRTM 1 Second Hydrologically Enforced
  • 5 metre Digital Elevation Model (DEM) – this delivers 1m, 5m, 25m contours

I downloaded 5m DEM data covering part of the 2015 Anglesea mtbo map, imported contours into OCAD and overlaid those on the OCAD map file of 5m contours. The correspondence was very close which is a tribute to mapper John Sutcliffe as much as to the ELVIS data.

The Coverage

The 5m resolution coverage, which provides down to 1m contours, is fairly thin. These surveys cover Australia’s populated coastal zone; floodplain surveys within the Murray Darling Basin, and some parts of  major and minor population centres.

Maybe we will see more sand dune coastal area maps akin to those near Hobart,  Auckland, Levin and Invercargill. And perhaps street and park-O where more detailed contours are desired.

Ease of use

The website isn’t yet the friendliest until you get to know it and then it does work well. Here are tips based on my learning;

Symbols of available datasets1m Hydrologically enforced DEM

  • Selecting  a right arrowhead symbol provides a synopsis of that data type.
  • Selecting a download arrow symbol takes you to the selection of data coverage for your project.
  • Selecting the globe symbol, (red when selected) shows on the map at left, the available coverage for that data.
  • Selecting the ‘eye’ symbol (orange when selected) show the extent of  that data coverage.
  • Note the latter two symbols act like check boxes, not radio buttons.
map of ELVIS 5m data coverage, eastern states
ELVIS 5m data coverage, eastern states

 Selecting a 5m dataset5m DEM for Victoria

  • At time of writing, selecting the name of any state 5m dataset gives you identical national information. It also has links at right (when selected) to state mosaic downloads – these are of no relevance to OCAD use.
  • Selecting the download icon frames the 5 metre DEM coverage area for that state.

Download of data

Whichever dataset you choose, the method of selecting data is the same. The download wizard is easy to follow.

  • For Output Format, select Esri ASCII Grid for OCAD import. The file will be a .asc type file.
  • For Coordinate system, select GDA94 for OCAD import.

OCAD import

The easiest method is to use the DEM import wizard available in OCAD 12 (OCAD 10 & 11 users, see the video tutorials link below); http://ocad.com/wiki/ocad12/en/index.php?title=DEM_Import_Wizard. The defaults provided in the wizard are adequate for a first run.

You can select 1m, 5m and 25m Contour Lines and produce background maps of any or all of Slope Gradient, Hill Shading, Hypsometric Map.

Tutorials

There are 4 video tutorials on DEM at http://ocad.com/en/support/learn-video. These videos are useful for OCAD 10, 11 and 12 users.

I created a 4 minute video tutorial on the basics of using ELVIS. View it online at www.screencast.com/t/y3MTbMzzO

And here is a base OCAD file I created to import the DEM data and then in turn it is imported into your OCAD map file with minimal symbology and colours.

ELVIS issues

ELVIS striation issue Wilsons Prom
ELVIS striation Wilsons Prom

Russell Rigby detected an issue that is mainly evident in steeper areas. The contours have a degree of blockiness or striations. Russell has made Geoscience Australia aware of this issue.

This is strongly evident in the steep Wilson’s Promontory contours at right.

It is less evident but still distinguishable as a series of  ‘steps’ in the less steep Preston contours below right.

In many orienteering areas, the issue won’t be much of a problem. For example in the Anglesea contours, I had to inspect closely to detect the striations.

 

ELVIS improvements

ELVIS striation issue Preston
ELVIS striation Preston

Russell Rigby and myself have made contact with ELVIS re suggested improvements and data quality concerns. We each received responses that indicate a will to continue product improvement.

Credits

Russell Rigby, ONSW mapping convenor for his experiences of ELVIS.

Geosciences Australia for releasing an easily accessible pool of LiDAR data.

NASA for the Creative Commons licenced image of 1998 storm Elvis over USA and Atlantic.

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From GPS and Google Maps to Spatial Computing

Curious about spatial computing? Or more than curious?

Course logo
Course logo

This course from the University of Minnesota via Coursera delves into spatial computing for geographic information systems (GIS). Now that might seem heavy going but the course caters for three different goals of participants;

  • Curiosity – learn about one or two spatial concepts of interest to you
  • Concepts – learn about spatial concepts but not get involved in programming or statistics
  • Technical – the lot!

Why might this course interest you?

If, like me, you use data from various sources then you will doubtless have run into issues ranging from data formats to co-ordinate systems to projections to …. So you might want more than a passing knowledge of what you are dealing with.

I am hopeful the Curiosity track will increase my knowledge of co-ordinate systems and projections so I can bother Russell Rigby a little less. And if I can get through at least some of the Concepts track maybe I will further broaden my knowledge of ESRI Shape files and the like as I use them in nearly every map I produce.

This course introduces concepts, algorithms, programming, theory and design of spatial computing technologies such as global positioning systems (GPS), Google Maps, location-based services and geographic information systems. Learn how to collect, analyze, and visualize your own spatial datasets while avoiding common pitfalls and building better location-aware technologies.

Best of all…

It is free unless you specifically want a certificate of attainment.

You will find out that egocentric maps exist but they are not necessarily your maps 🙂 And did you know orienteering maps are allocentric?

Sign up here. But be warned, it does take a fair bit of time and commitment. 8 weeks of 4-10 hours per week. However I understand you have until Christmas to complete it.