WorldView 2 image Marmion Marine Park, Western Australia
June 2nd 2012, 11800*12500, 2 m ground resolution, 24.6 km * 25 km
 
image from Digital Globe
"(c) DigitalGlobe, Inc. All Rights Reserved"
"Includes copyrighted material of DigitalGlobe, Inc., All Rights Reserved"
work done in 2013
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Now, using the Panchro channel
and a suitable coverage of deep waters areas and of land areas


bands 1, 2, 3, Panchro, 4, 5, 6, 7 and 8       
become      
bands 1, 2, 3, 4, 5, 6, 7, 8 and 9
Following several attempts using a limited WV2 MULTI and PAN
coverage of Marmion Marine park provided by Simon Allen, CSIRO,

DigitalGlobe provided me on Dec_12th_2012 with this new MULTI+PAN dataset,

which covers 65000 lines at 2 m ground resolution

to provide a good coverage of optically deep water areas and of land areas:

 

It is comprised of 22 tiles over two adjacent full segments

  • MULTI is comprised of

    • 12JUN02025337-M3XS_R01C1-052870327010_01_P001, tiles RO1C1 to R11C1

    • 12JUN02025403-M3XS_R01C1-052870327010_01_P001, tiles R01C1 to R11C1

  • PANCHROMATIC is comprised of
    • 12JUN02025337-P3XS_R01C1-052870327010_01_P001, tiles R01C1 to R11C1
    • 12JUN02025403-P3XS_R01C1-052870327010_01_P001, tiles R01C1 to R11C1
    •  
 

perth-mosaic-data
perth-mosaic-pan
perth-mosaic-calibration
perth-mosaic-results

This below is the mosaic of
tiles 2 and 3 of twin stripes, 11800x12500, 24.6 km x 25 km

Panchro band
4x4_sum_aggregated to 2 m ground resolution
 
  • The extent of Marmion Marine Park is shown
  • Please note the plume of industrial smoke
  • Pan band does not exhibit bottom detection away from park limit
  • Black areas are below deep water radiance: this is negative bottom contrast
Green band

 
  • Profile_red is shown (see below)
  • Profile_yellow is shown
  • Green band exhibits bottom detection up to 6 km away from park limit along Red profile

Blue band
  • Blue band appears to exhibit bottom detection up to 10 km away from park limit along Red profile

 
Purple band
  • Purple band does not exhibit bottom detection beyond park limit along Red profile
  • Note the bad striping which affects shallow areas where very dark
  • Bad luck: most of the shallow areas are quite deep and most bottoms are quite dark, consequently,
    • vast areas in Marmion Park are at deep water radiance: no result may be obtained
    • some areas are below deep water radiance: quite tricky/risky to process
  • Bad system noise
  • Bad timing: add to it that this image was acquired in june: an image acquired in december or january would be much brighter:
    • more photons collected result in improved performances of shallow water work!
    • is there such an image in DG's archive?









 
Date of multibeam survey?
  • This image was acquired June 2nd 2012
  • When was the multibeam survey conducted?
  • Can the bottom topography have changed significantly since that survey?
    • probably not because the sedimentary cover is said to be "a thin (< 1m), spatially variable veneer of unconsolidated calcareous sediment"
Profile Red shows raw data
  • negative bottom contrast: note that a few sections exhibit slightly negative bottom contrast in bands Purple, Blue and Panchro, but not in the Green band
  • PAN: note that, apart for the striping, the PAN sum_aggregated band has 16 times less noise
  • Red band is erratic
 



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