Abstract
It is often stated that there is no point in obtaining mid-infrared data with S/N>20, even in the best of cases, because it is impossible to obtain a calibration to better than 5%, although in many cases 10% or greater is a more accurate reflection of the true quality of calibration. Mid-infrared calibration is difficult because of the lack of measured standards and their generally poor quality and also because of the rapid variability of the atmospheric transparency that requires great care to be taken. The mid-infrared standards that have served for a generation of 3~m class telescopes are found to be inadequate for the new generation of 8--10~m class telescopes as the sensitivity of a telescope in the mid-IR goes as the fourth power of the increase in diameter. We describe our efforts to prepare a new set of mid-infrared standards adapted to the needs of 10~m class telescopes as a part of the photometric, spectrophotometric and polarimetric calibration for the CanariCam project (Martín-Luis et al.~2001).
