Issues creating a mosaic

Discussion created by barneyharris on Feb 12, 2014

I've had various problems creating my mosaic of landsat imagery obtained from USGS

Ive had got many various images as I wish to investigate the whole state of Maranhao and thus have many images to mosaic together.

When I initially mosaiced the black outline was still there on every image so I have removed this by displaying no data as no colour yet now it has been left with areas of dull patches where the black backgrounds once where. Should I have clipped all the images prior to mosaicing?

The reason I am using this is to ***** forest cover change and so ultimately will need to classify the image and thus don't want this dull area causing issues in not assigning correct land.

Finally I was wondering if masking would be my best option for clipping my polygon so I just have the state of marnahao showing, as I have tinkered with a few methods but as of yet am struggling due to the awkward shape.

Any help or advice will be greatly received