SRTM_Mask
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Now we are finally ready to wipe out the ocean and make it totally white. This procedure will complete eliminate the remainder of the noise from our mask.
Switch to the "Magic Wand Tool" on the floating toolbar.
Set the "Tolerance" to "1" and make sure "Contiguous" is selected.
"Tolerance" defines how closely a pixel can be associated to the pixel we inevitably click on with the "Magic Wand Tool" that will be the deciding factor as to whether it is included in the selection set or not.
"Contiguous" defines whether the final selection incorporates all pixels associated with the values of the pixel we inevitably click on across the entire image, or simply one continuous block of pixels within a localized region around the one eventually selected, falling within the range of the "Tolerance" value of course.
Setting "Contiguous" to off, would select ALL the black pixels on the entire image, including the noise. We only want to select the land areas within the boundary that we have spent all this time defining.
Navigate to the menu option "Select->Inverse" or press "Shift+Ctrl+I" on the keyboard.
The selection will invert itself.
Check again to make sure the secondary color in the floating toolbar is pure white, not pure black.
Press "Del" on your keyboard. The noise should vanish and be replaced by white. If the entire ocean area is replaced by black, then you didn't do what I just said in the line above. -> Check again to make sure the secondary color in the floating toolbar is pure white, not pure black.
Once you've made a mistake it's easy to fix.
Jump to the Fixing mistakes page.
Click on the image for a larger view.
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