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Find a place
- You can type in a place name
- You can enter lat, long, such as N22.62, E31.25. If you do
this, it will zoom in to a scale where you see basically a postage
stamp. You should back up until the image is not fuzzy, and
perhaps a little farther to insure you are seeing the big picture of
what is at that location. If the coordinates have only two
decimals like the ones here, they are only accurate to the nearest
km.
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Choose rendering
- Agriculture (enhanced green which is actually NIR)
- Natural color (plants not as obvious)
- Color infrared (false color, with NIR shown in red, most common
choice to show vegetation health)
- Panchromatic (only on Landat, but has the best spatial
resolution; Sentinel-2 has better spatial resolution in the
principal bands without a pan band)
- Vegetation index (NDVI): (NIR-red)/NIR + Red), where plants will
be > 0.4 or so, and water will be very low
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Time selector
- Pick dates, cloud filter, or season
- Click on the map and get a temporal profile graph
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Time selector, Temporal Profile
- This graph shows the time series, clearly showing when irrigation
and crops arrived.
- By clicking on the points, you can change the map display and see the
change.
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Mask
- Pick Vegetation index (or other)
- Set transparency, so you can see the satellite imagery
poking through
- Adjust the mask value, so all the fields are colored, and not the
surroundings
- Get the area in the upper right of the control window
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Swipe
- Pick two dates
- Move the slider back and forth
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Change detection
- Pick two dates
- For more control, try the difference mask or threshhold mask
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Identify
- Scene information
- Spectral profile, and comparison to common materials
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Identify
- Scatter plot, pick two bands
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Export
- Export creates a TIFF. You want the current render (unless you
intend to use the image in a GIS program), and it might only export the
mask or overaly.
- It might be easiest to use Snip or Print Screen, and then crop to what
you want.
- Export for Sentinel-2 requires ArcGIS Online account ($$$, or
free limited public account)
- Export removes the scalebar and location
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