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	Figure 1: Transmission curves of the Spitzer and ISO filters used to survey the Lockman Hole on the M 82 SED (dotted lines) put at the redshift of z=0., 0.5, 1, and 1.5. The LW3 data remain unique also after the Spitzer observations since the most important PAH features pass through the LW3 filter in the redshift range z=0-1.5.
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In the text

Figure 3: Four examples of reduction of part of one pixel data with the Lari et al. (2001, on the left) and the PRETI ( on the right) methods. Vertical lines separate the readouts for each pointing of the camera. Raw data, model, and reconstructed signal are marked with thin, thick and dotted lines, respectively. In these four cases the PRETI method fails to detect the sources close to glitches or in negative parts of the signal.

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In the text

	Figure 5: The ratio between measured and predicted fluxes for 21 stars detected at 14.3 m in the Lockman Hole shallow survey. Errorbars take into account the error on the photometry and the error in the predicted fluxes. The median of the points is 1.0.
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In the text

Figure 6: Number of glitches per frame versus exposure time per sky pixel for the ISOCAM deep surveys (LHD and LHS, Lockman Hole Deep and Shallow, HDFN and HDFS, Hubble Deep Field North and South, MD, Marano Deep, UD1 and UD2, Ultra-deep fields in the Marano field). The number of glitches in the signal due to cosmic ray hits are computed for glitches which are 5 times bigger than the rms of the signal for each pixel. The surveys with the longest scans (LHS and MD) have the lowest number of glitches.

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In the text

	Figure 7: Fraction of simulated sources detected as a function of the input flux. Bars correspond to the 1- Poissonian errors. The survey is 50% complete at 0.6 mJy
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In the text

Figure 8: Astrometric accuracy versus SNR for simulated sources (empty circles) and real sources (filled triangles) compared to their optical counterparts. The points correspond to 1, i.e. the distance inside which one finds 68% of the counterparts. The lower and upper limits (errorbars for the real sources and shaded area for the simulated ones) correspond to the distances inside which one finds 50% and 80% of the points, respectively. The distances of the simulated points have been quadratically added to the pointing accuracy.

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In the text

	Figure 9: Difference in position between the infrared sources and their optical counterparts. The diameter of the external circle corresponds to the LW3 beam (4.7 ), while the internal circle contains 68% of the points (2 ). The stars are indicated with filled dots.
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In the text

	Figure 10: Distribution of fluxes of detected sources with respect to the input flux of the simulated sources. Gaussian curves have parameters computed by means of a biweight estimator.
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In the text

	Figure 11: Comparison of flux estimates for sources detected in both the shallow and deep Lockman Hole surveys. The caustics represent the 1 photometric errors. Below the 20% completeness limit, we detect an increasing number of faint sources enhanced by positive oscillations of the noise.
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In the text

Figure 12: Comparison between sources detected in the central region of the field by the shallow and deep surveys. Top panel: black dots are sources detected in the two surveys while empty triangles only in the shallow one. Bottom panel: total number of sources in the shallow survey (solid line) and shallow detection not present in the deep survey (shaded histogram). Sources brighter than 0.45 mJy have a high degree of reliability.

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In the text

Figure 13: Four optical counterparts of 14.3 m sources. SNR levels of 5, 7, and 10 have been overlapped to the r' image. The two images on the top have a field of 2 2, the two on the bottom of 20 20 . In the top left corner the only IRAS source in the field, NGC 3440, which is resolved in two components. At the top right and bottom left, two examples of interacting galaxies. At the bottom right, faint optical counterpart of a strong mid-IR source.

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In the text

	Figure 14: Cumulative counts for sources, galaxies, stars and blank fields are marked with dashed, solid, dotted and dash-dotted lines, respectively. For fluxes greater than 0.6 mJy (50% completeness limit), 21% of the sources are stars and less than 2% are blank fields in our r' image.
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In the text

	Figure 2: Coverage map of the Lockman Hole shallow survey. Dark regions correspond to the overlapping of raster scans (350 s of exposure time), while the typical coverage of grey regions is 200 s. Arrows indicate the in-scan (IS) and cross-scan (CS) directions.
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In the text

	Figure 4: SNR image of the total field observed by ISOCAM in the direction of the Lockman Hole. The 21 stars used to check the calibration flux factor are marked with circles.
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In the text