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Geomatics Acronyms and Abbreviations

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Geomatics has become a pretty common term in Canada lately and includes many different disciplines such as geographic information systems (GIS), remote sensing, cartography, land surveying, global navigation satellite systems (GNSS), photogrammetry, geography and other related forms of spatial mapping.

Using acronyms and abbreviations is commonly practiced in the Geomatics industry and most of the time people just assume that everybody else knows what every acronyms and abbreviation stands for. Well that is obviously not the case most of the time and over the years I have created myself a little digital cheat-sheet of geomatics acronyms and abbreviations that I use with my work in my writing.

Here is a large collection of common acronyms and abbreviations related to the Canadian Geomatics industry: http://canadiangis.com/geomatics-acronyms-and-abbreviations.php

Converting between UTM, MTM and LAT/LONG

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Canadian using a UTM map

Geographic coordinate systems enable us to spatially locate features on the Earth using specified set of two dimensional numbers. The coordinates of each feature represent the horizontal position (and sometimes vertical position when elevation is available) of it and one of the most commonly used coordinates is Geographic with values of latitude, longitude. However many different coordinate systems can be used to map the same area depending on various factors such as map extent, scale, end user etc. Therefore we often find in Geomatics that we can have data from different coordinate systems that we need to use together spatially in one reference system.

I am sure that most of us have run into times when we have features that have defined coordinates of one system that we need to use with a different one. (E.g. your map is in UTM (Universal Transverse Mercator) but you have been given GPS points in Lat/Long).

If you ever find yourself in need of quickly getting values converted from Geographic to UTM / MTM (Modified Traverse Mercator) or UTM / MTM to Geographic then here is a a free online geographic coordinate convertor tool that I often use provided by Canadian Spatial Reference System

CanadianGIS

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CanadianGIS.com is an extension of my web site that I started back in 2005 after I noticed that there was a real need to have somewhere on the web to help find Canadian GIS resources. And although there were a few other websites starting around that time related to GIS, nobody else was really dedicating a site to Canadian GIS topics.

CanadianGIS.com logoThe site has evolved slightly since then with a few functions or sections being added to it or removed as time went on but it has always been primarily used to promote the Canadian GIS & Geomatics Industry and to share information with other Canadians that also have an interest in GIS. It also went well together with GISjobs.ca, another GIS site that I created to help Geomatics students find Canadian GIS & Geomatics related jobs much easier. GISjobs.ca turned out to be a real success and eventually led to the creation of GoGeomatics, another Canadian Geomatics job board site that allowed people to post GIS jobs for free (now is fully fee based).

CanadianGIS.com helps provide people with resources about Canadian GIS & Geomatics related data, basic information about Canadian companies that provide geomatics services, locations of Canadian data and maps, information about GIS conference & events, places to find Canadian GIS employment and education info and many other great resources. Content for the site been created by me and a few volunteers, with some also being supplied by various GIS companies and academic institutions.

If you have not yet checked the site out then I encourage you to go and see for your self, and if you discover that there is information related to Canadian GIS resources that I have missed then please do let me know. – Join the Canadian GIS LinkedIn Group (2200+ members) or the Canadian GIS FaceBook Group (2100+ members but mostly different from the LinkedIn group)

regards,

Ted MacKinnon -Geomatics Specialist

tmackinnon.com

Contact Me: email

Twitter: @tedmackinnon or @CanadianGIS

LinkedIn: tedmackinnon

FaceBook: ted.mackinnon

[page originally published in Jan. 2009]

Real Time Kinematic (RTK) Surveying Guidelines

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Real Time Kinematic (RTK) surveying with Global Navigation Satellite Systems (GNSS) Over the past decade Real Time Kinematic (RTK) surveying with Global Navigation Satellite Systems (GNSS) has become common practice in geomatics. RTK surveying can allow people to achieve relative positioning with centimetre (cm) precision, however there are several important factors that need to be considered and thus a need for a good guide of best practices (equipment calibration, errors, multipath, geometry, etc.). Therefore Natural Resources Canada (NRCan) put together a new set of guidelines for Real Time Kinematic (RTK) Surveying.

You can download the 29 page PDF document with the following link

http://webapp.geod.nrcan.gc.ca/geod/publications/pdf/Canada%20RTK_UserGuide_v1%201_EN.pdf

[Find more info on RTK surveying my other website]

Color Shaded Relief Models

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Traditional images in geomatics are often two dimensional, meaning that all data in the image can be referenced by X and Y coordinates.
Three dimensional color shaded relief (CSR) perspective view of high resolution LIDAR

Three dimensional images (3D) incorporate a third dimension (the Z component) which represents the elevation or depth aspect of the data. To incorporate it into an image requires creating special geomatics value added products that allow users to perceive the presence of the third dimension into a traditional two dimensional setting (because most paper and computer screens are flat or two dimensional).

A color shaded relief (CSR) utilizes chromo stereoscopic techniques to help emphasize the depth of the Z dimension from traditional shaded relief models that already portray the presence of an elevation difference. Using carefully edited RGB (red, green, blue) pseudo colors and then encoding them into the shaded relief image provides the user with an even more enhanced feeling that they can perceive a third dimension from a two-dimensional medium (also helping to quickly decipher between high and low elevated regions). When a feature of the same color in the image is shaded darker than the shade of its background, then the background color will predominate in determining its perceived depth position in the image.

Color shaded reliefs utilize chromo stereoscopic techniques to help emphasize the depth of the Z dimension from traditional DEMs

There are several different software packages that can be used to create CSR models, but I have found that Geomatica software by PCI Geomatics has proven to produce some of the better results in CSR models generated from DEMs. ChromaDepth 3-D glasses can often be used to further enhance the three dimensional feeling as well. These glasses use sophisticated micro-optics technology to transform color images into stereo 3-D. If you do not currently have PCI Geomatica then you can obtain a trial copy of it from their web site; then follow the steps outlined in the following CSR tutorial.

Here are some more Examples of some of the many color shaded relief (CSR) models that I have created

Orthophoto & LIDAR CSR for New Brunswick

Color Shaded Relief related documents:

 

House of Cards Music Video

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Always cool to see Geomatics technology used for non traditional geomatics uses!

Here Radiohead’s new music video was not created with any traditional video cameras but instead they used 3D LIDAR scanning technology.

Actual Radiohead Music Video:

Making the Music Video:

Remote Sensing

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Remote sensing is merely the science of acquiring information about a surface without physically being in contact with it. It involves the use of technical instruments or sensors to record reflected or emitted energy and then processing, analyzing, and applying that information to determine the spectral and spatial relations of distance objects and materials.

Remote SensingThis is possible due to the fact that the examined objects (such as vegetation, buildings, water, air masses etc.) reflect or emit radiation in different wavelengths and intensities according to their current condition. Modern remote sensing typically involves digital processes but can also be done with non-digital methods.

Probably the most common example of remote sensing is an aerial photograph but there are probably hundreds of applications related to remote sensing ranging from space-borne satellites to under-ground geophysical systems. It has become a major component in the evolving Geomatics industry. In order to generate maps for GIS, most remote sensing systems expect to convert a photograph or other data item to actual measurable distance on the surface. However, this almost always depends on the precision of the instrument that is being used to capture the data. For example, distortion in an aerial photographic lens can cause severe distortions when photographs are used to measure ground distances. Using sophisticated software like PCI OrthoEngine can convert the photograph into an ortho photo which can be used to measure ground distances.

In order to coordinate a series of observations, most sensing systems need to know where they are, what time it is, and the rotation and orientation of the instrument. High-end instruments now often use positional information from satellite navigation systems. The rotation and orientation is often provided within a degree or two with electronic compasses.

The resolution determines how many pixels are available in measurement, but more importantly, higher resolutions are more informative, giving more data about more points. However, large amounts of high resolution data can clog a storage or transmission system with useless data, when a few low resolution images might be a better use of the system.

Like I mentioned earlier examples of remote sensing are very numerous. I have over the past decade and have used the many projects that I have been involved with along with actual examples of my work to help illustrate the principals of the various topics covered on the web site. I have included basic overviews for each along with images, presentations, papers and links to other related resources.

Examples of Remote Sensing

Remote Sensing Links

Color Shaded Relief Models – Cap Pele, New Brunswick

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Color Shaded Relief Models of Cap Pele, New Brunswick Color Shaded Relief Models of Cap Pele, New Brunswick

The two images above represent artificial three dimensional perspective views perspective views from different points of origin featuring color shaded relief models that were created from high resolution LIDAR digital surface models as part of a LIDAR flood modeling graduate research project.

The study area for the project consisted of the coastal Gulf Shore region of southeastern New Brunswick from Kouchibouguac National Park south to Jourimain Island (location of the Confederation Bridge). The coastal zone of New Brunswick is a picturesque fishing region that boasts several kilometers of sandy beaches with some of the warmest salt water temperatures north of Virginia.

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