Elevation Transformation using QGIS
Steps for Converting Elevation Values from Meters to Feet in QGIS
Step 1: Check Raster Values
First, make sure the raster values are in meters. You can do this by:
1. Right-clicking your elevation raster layer in the Layers panel.
2. Selecting Properties and going to the Information tab to verify the data units and value range.
Step 2: Open Raster Calculator with Correct Formula
1. Go to Raster go to Raster Calculator.
2. In the Raster Calculator dialog, type the conversion expression carefully:
"elevation_raster@1" * 3.28084
Note that @1 is often necessary in QGIS if you're using the first band of the raster. Ensure you double-click the layer from the Raster bands list on the left side, so it appears exactly as shown in the formula above.
Step 3: Set Output File and CRS
1. Choose a location and file name for the Output layer.
2. Ensure that the Output CRS (coordinate reference system) is set correctly. Sometimes, a mismatch in CRS may cause issues with scaling.
Step 4: Run and Verify the Output
Click OK to run the calculation, and check the result:
• Use the Identify Tool to inspect pixel values.
• Confirm they reflect the conversion from meters to feet (e.g., a pixel originally at 1000 meters should now read around 3280.84 feet).