In the use of carbon thin films as. a technological material, accurate information on the microstructural and,chemical composition is crucial. Despite great advances in the analytical capabilities of advanced instruments, few techniques give more information than electron energy loss spectroscopy (EELS). When EELS is coupled with a transmission electron microscope, sub-nanometre resolved chemical and structural information can be obtained about the properties of the thin film. In this paper we discuss the information that is available on the bond hybridisation, and ways in which to improve the accuracy of the experimentally determined pi to sigma ratio in carbon films. We use the line focussing properties Associated with the quadrupoles of a Galan Imaging Filter in a Transmission Electron Microscope to characterise the electronic and materials properties across a nano-heterojunction. This technique, when fully developed, would allow for a larger research community to have access to a relatively cheap non-contact methodology for the characterisation of the electronic properties of nano-heterojunctions. We demonstrate the technique by investigating WS2-coated multi-walled carbon nanotubes at the interface between the coating and the nanotube, as a function of the coating's thickness. This is done by examining the relative change in the effects on the plasmon resonance due to the hollow geometry and the anisotropic electronic structure of the coated nanotubes, with changing coating thickness. We also examine the properties of diamond-like carbon thin films on a nanometre scale, in order to explore the possibility of fabricating amorphous carbon based superlattices for electronic applications. (c) 2005 Elsevier B.V. All rights reserved.