InfraTec offers a wide range of special spectral filters for thermographic measurement of the most different materials and applications. Those filters can also be customized. Both the infared camera systems of the ImageIR ® series as well as the long-wave uncooled VarioCAM ® hr head cameras provide facilities for a mounting close to the detector within a filter wheel or a filter slider. The filter wheel of the ImageIR ® models is especially convenient as filters can be changed remotely controlled and motorized. Warm aperture effects caused by a filter position in front of the lens and resulting in possibly big measurement errors can be avoided by such positioning close to the detector being possible in infrared camera systems of InfraTec.