Using FME i want to reproject an ECW image to EPSG:3857 from EPSG:28354.

I intend to sit this image(and many more) over a large mosiac.

Using CSMapReprojector this re-projects with a boarder. I've read other discussions about how to clip and set the nodata value but none seem to work.

Can anyone please suggest the right method for this

Example below is something i've tried (also with the RasterNoDataSetter but to no success). I think it has something

I think i'm failing due to the varying RGB values in the black collar area as below