We have determined extinction corrections for a sample of 441 late-type stars in the inner Galaxy, which we previously searched for SiO maser emission, using the 2MASS near-infrared photometry of the surrounding stars. From this, the near-infrared extinction law is found to be approximated by a power law A_lambda_{prop.to}lambda^-1.9+/-0.1^. Near- and mid-infrared colour-colour properties of known Mira stars are reviewed. From the distribution of the dereddened infrared colours of the SiO target stars we infer mass-loss rates between 10^-7^ and 10^-5^M_{sun}_/yr.

Cone search capability for table J/A+A/435/575/table3 (Interstellar extinction estimates Ak in the direction of SiO targets)