Oops. I apparently didn't try the simplest thing: raster <- readGDAL(path) # a 1000 x 1000 raster raster$band1 <- array(data = 1, dim = 1000000) writeGDAL(raster, fname = '/tmp/foo.tif', driver = 'GTiff', type = 'Byte', mvFlag = 255) Cheers, Chris -- Christopher Swingley Fairbanks, Alaska http://swingleydev.com/ cswingle at gmail.com