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Our MIR observations were obtained using ISOCAM, a 32$\times$32 pixel array [@CesarskyC1996] on board the ISO satellite [@Kessler1996]. Each system was observed with broad band filters ranging from 5 to 18$\mu$m in a 2$\times$2 raster with 6 pixel offsets and a lens producing a pixel field of view (PFOV) of 1.5, resulting in a final image of 57$\times$57. This enabled us to obtain images with a spatial resolution of 3 (at 6$\mu$m) to 4.5 (15$\mu$m) limited by the pixel size at 6$\mu$m and by the full width at half maximum (FWHM) of the point spread function (PSF) at 15$\mu$m. We note the ISOCAM filters by their name and central wavelength. The wavelength range in $\mu m$ covered by each filter was: LW2 (5.0 – 8.5), LW3 (12.0 – 18.0), LW4 (5.5 – 6.5), LW6 (7.0 – 8.5), LW7 (8.5 – 10.7), LW8 (10.7 – 12.0), LW9 (14.0 – 16.0). At subsequent sections in this paper we will refer to the measured flux densities using the various filters as f$_{x\,\mu m}$ where *x* is the central wavelength of each filter in microns.

Spectrophotometric observations were also obtained with the circular variable filter (CVF) for IRAS 23128-5919, the brightest of our 