QGIS/C2/Coordinate-Reference-Systems/English
| Visual Cue | Narration |
| Slide Number 1
Title Slide |
Welcome to this tutorial on Coordinate Reference System in QGIS. |
| Slide Number 2
Learning Objectives |
In this tutorial, we will learn to,
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| Slide Number 3
System Requirement |
To record this tutorial I am using,
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| Slide Number 4
Pre-requisites
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To follow this tutorial you should have basic knowledge about GIS.
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| Slide Number 5
Coordinate Reference systems |
About Coordinate Reference Systems,
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| Slide Number 5
Coordinate Reference systems |
Most widely used geographic coordinate system is WGS 84.
Most widely used projected coordinate system is UTM. |
| Click on QGIS icon to open the interface.
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Here I have opened QGIS interface.
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| Slide Number 6
World Map File |
Demonstration on how to download the map and display in QGIS is explained in the prerequisite tutorial.
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| Cursor on layers panel on name of the map file. | On the left-side of the canvas, you will see Layers Panel, with file name of the world map as a layer. |
| Cursor on the canvas. | By default Layers Panel is enabled here.
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| Click on View tool on the Tool bar.
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Click on View menu on the menu bar.
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| Scroll down and select Panels option.
From the sub-menu, click on Layer Panel. |
Sub-menu shows a list of panel names.
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| Drag the boundary with the mouse. | We can adjust the size of the panel by dragging the boundary. |
| Right-click on the layer name in Layers Panel.
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If you wish to change the color of the map, right-click on the layer name in the Layers Panel. |
| Scroll-down the context menu and select Styles option. | Scroll-down the context menu and select Styles option. |
| Rotate the vertex of the color triangle to choose the color.
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Sub-menu shows a color triangle .
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| Click anywhere on the canvas. | Click anywhere on the canvas to close the context menu. |
| Cursor on Coordinate label and text box.
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At the bottom-left corner, on the status bar of QGIS window, you will notice
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| Highlight X and Y coordinates. (Editing stage) | Values of X and Y coordinates for a particular location are shown in this text box. |
| Move the cursor over the map.
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Move the cursor over the map.
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| Cursor on Render option. | By default Render option is checked on the status bar.
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| Point towards EPSG:4326(OTF) on the bottom-right corner of the status bar. | On the status bar, at the bottom-right corner, you will see another label, Current CRS.
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| To determine a layer’s projection, we can look into the metadata. | |
| Right click on the Layers Panel, ne_10m_admin_0_countries | On the Layers Panel, right-click on the layer name. |
| From the context menu, select Properties.
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From the context menu, select Properties.
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| Click on Metadata option in Layer dialog-box.
Scroll down. |
In the dialog-box, on the left-side panel, click on Metadata option.
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| Point to heading, Layer Spatial Reference System.
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At the bottom,
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| Click Ok button | Click on Ok button at the bottom, to close the dialog box. |
| Let us now add layers to the map and change the projection. | |
| Slide Number 7
Data layers |
About data layers.
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| Back to the QGIS interface. | |
| Cursor on the QGIS canvas. | Now let us see how we can change the layer’s projection.
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| On top-right corner of the tool bar >> click on Select features by area or single click tool. | On top-right corner of the tool bar, click on Select features by area or single click tool. |
| Click on the black triangle next to this tool. | Click on the black triangle next to this tool. |
| Drop down >> choose Select features. | From the drop down choose Select features. |
| On the canvas, on the world map, click on United States of America. | On the world map displayed on canvas, click on the United States of America feature to select it.
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| Cursor on the map. | We will now change the projected coordinate system of this layer and save. |
| Right click on ne_10m_admin_0_countries | Right-click on the layer name in the Layers Panel. |
| Click on Save As option | Scroll down, select Save As option. |
| Save Vector Layer as dialog box opens.
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Save Vector Layer as... dialog box opens.
Leave it as such. |
| Click on Browse button. | Click on Browse button next to File name text box. |
| Save layer as... dialog-box opens.
In the name text box, type the layer as USA-1.shp. |
Save layer as... dialog-box opens.
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| Click on Desktop option.
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Find a suitable location to save.
I will save it on Desktop Click on Save button at the bottom. |
| In the Save Vector Layer as... dialog-box.
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In the Save Vector Layer as.... dialog-box, the file path appears in the File name text box. |
| Click select CRS button next to CRS text box.
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We will choose the new projection for this layer.
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| In the Coordinate Reference System Selector dialog box, type North America
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| Click North_America_Albers_Equal_Area_Conic
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| Click on OK button. | Click on OK button at the bottom. |
| In the Save vector layer as... dialog-box, cursor on CRS drop down box. | In the CRS drop down box, the newly selected CRS is shown. |
| In the Save Vector Layer as dialog-box,
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Click on the check box to check Save only selected features option.
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| Cursor on , Add saved file to map. | Here, by default, Add saved file to map option is checked.
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| In the Save Vector Layer as... dialog-box, click on OK button | Click on OK button at the bottom. |
| Point on united states outline.
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The re-projected layer gets loaded, in a different color.
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| untick enable on the fly CRS transformation
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Notice that the new United States layer overlays perfectly on top of the world map layer.
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| At the bottom-right corner, click on EPSG:4326.
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Select United-States layer in the Layers Panel by clicking on it.
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| Cursor on Project Properties CRS dialog-box. | Project Properties CRS dialog-box opens.
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| Uncheck Enable on the fly CRS transformation check box,
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Uncheck Enable on the fly CRS transformation check box, by clicking on it.
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| Cursor on the map. | Back in the main QGIS window, you will see the world map disappear.
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| Right click on USA-1.shp layer.
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The coordinates and scale are different now.
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| Click on EPSG
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Again, click on the Current CRS text to open Project Properties dialog-box.
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| Under the heading Recently used Coordinate Reference Systems, select WGS 84.
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Under the heading Recently used Coordinate Reference Systems, select WGS 84.
At the bottom, click on the OK button.
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| Right-click on USA-1.shp in Layers panel.
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To delete the vector layer from the dataset, right-click on the name in Layers panel. |
| Click on Remove option from the context menu.
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From the context menu, click on Remove option.
Click on OK button. |
| Cursor on the layers panel. | Observe that the layer is removed from the dataset. |
| Slide Number 10
Summary |
Let us summarize,
In this tutorial we have learnt to
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| Slide Number 11
Assignment |
As an Assignment:
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| Show completed assignments. | Your completed assignment should look like this. |
| Slide Number 12
About Spoken Tutorial project |
The video at the following link summarizes the Spoken Tutorial project.
Please download and watch it.
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| Slide Number 13
Spoken Tutorial workshops |
The Spoken Tutorial Project team:
conducts workshops using spoken tutorials and gives certificates on passing online tests. For more details, please write to us. |
| Slide number 14
Forum for specific questions:
•Please visit this site •Choose the minute and second where you have the question •Explain your question briefly •Someone from our team will answer them
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Please post your timed queries on this forum. |
| Slide Number 16:
Acknowledgement |
Spoken Tutorial Project is funded by NMEICT, MHRD, Government of India.
More information on this mission is available at this link. |
| This tutorial is contributed by Prajwal. M from Sahyadri college of Engineering and Snehalatha from IIT Bombay.
Thank you for joining |