So I masked out an area of an image in Erdas a long time ago and these areas successfully display as 'NoData' (using the Identify tool) and are blacked out.
Today I masked out another area of the same image using SetNull so this area too is 'NoData'. However, my two areas of 'NoData' display differently and I was wondering why this is?!
When I change the colour of 'NoData' under symbology only one area changes whilst first area remains black.
Any ideas would be great.