Combined optical approaches. There are actually several proprietary optical smoke measurement devices like the 'nephelometer' or even the 'aethalometer' which use many various optical methods, which includes more than one wavelength of light, within an individual instrument and use an algorithm to give an excellent estimate of smoke. )[eighteen] https://edgardrfre.activablog.com/32807121/a-simple-key-for-tabacco-unveiled