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We propose deep CAM imaging of two high density cores in the archetypal quiescent cloud TMC-1. Such imaging will yield the actual density distribution of the cloud cores and the possible presence of first- protostars. Our recent experience with deep CAM imaging at 7 microns in the L183 dark cloud has shown that it is possible to detect absorption (see Fig. 1) by the very high density protostellar core regions, n_H2 10^6 cm-3, where CAM dust absorption is the ONLY reliable density tracer. What we observe in L183 may represent a very early shortlived phase in the birth of a star. These results motivated us to apply for discretionary time for a high sensitivity study of TMC-1, which is the most thoroughly observed and modelled dense molecular cloud to date and contains two dense cores which may be in a similar/later stage of star formation. TMC-1 is also a well observed cloud with ISO. It is part of a large ISOCAM guaranteed time mapping programme by LNORDH et al. (SURVEY_2), however their sensitivity is far too low to detect any absorption such as we have seen in L183, and to detect low-luminosity so-called "class -I" (Boss & Yorke 1995) first-protostars which lie between precollapse clouds and the class 0 protostars. We propose deep rasters of much smaller regions using microscanning and will approach the highest sensitivity achievable with ISO, up to a factor of 10 better than that achievable in the project of Nordh et al. Since TMC-1 is the prime testing object for astrochemical models, such a deep investigation is highly warranted. Deep high resolution dust absorption maps of the two cores at 7 microns in CAM LW2 would give a direct and independent estimate of the density distribution in this cloud. In addition we want to investigate if TMC-1 is truly quiescent by observing it at 15 microns in CAM LW3 which is sensitive to cold low-luminosity protostars. Due to the proximity of TMC-1 and the excellent sensitivity of ISO, we should be able to detect any point-like object for which the luminosity is higher than 10^-5 Lsun with ISOCAM. In case of a detection, this will be the first observation of a true protostar.