Increase image quality for plotted satellite data

I have plotted some satellite data on a worldmap using

surfacem(lat, long, data)

When I save the figure as .EPS the quality is not as good as I expect and alot of data pixels get lost. Does anyone know the underlying reason, and how I can get the figure into a tex-document with the same sharpness as in the .fig image?

The image looks like:

Thanks in advance Johan