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When good rivers turn bad: Extreme flooding
Finding hidden treasure

Try some more images

Finding zones of maximum turbulence in a cyclone

Cyclone
Courtesy of USGS Science for a changing world
http://astrogeology.usgs.gov

Change the colours in the palette

This exercise uses the 'Sharpen' feature of image enhancement. It is a mathematical routine that identifies and slightly darkens edge features. It is used to bring out outline shapes from blurry of fuzzy images but must be used with care. Overuse results in the image becoming granular.

Step 1:
Open the image-processing program. If you installed IrfanView program open it.

Step 2:
Click on the image of the cyclone to open a larger version and save it to your computer (cyclone1.jpg).

Step 3:
Open the saved the image of the cyclone from within the image-processing program.

Step 4:
Sharpen then reduce the colour depth of the image to 16 colours. Within Irfan's menu select a) Image > Sharpen > OK
b) Image > Decrease colour depth > select 16 colours > OK.

Step 5:
Change the colours to see if you can pick up more subtle changes in the cyclone.

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1. Origins of extreme weather | 2. Finding hidden treasure | 3. Streams and mass wasting
4. The Johnstone River, FNQ


The resources contained in this unit are courtesy of Earth Science Australia http://earthsci.org/