The Formatt Hitech 3 x 3" Combination Hot Mirror/IRND 2.4 Filter - Color shift is a critical factor in digital photography/videography and is directly affected by the infrared spectrum. This is particularly evident when using standard neutral density filters that absorb visible light but pass infrared.
Specifically, in high definition (HD) photography, the sensitivity of imaging sensors to IR has become a challenge for both photographers, videographers and manufacturers.
Digital cameras with their CCD or CMOS sensors are inherently susceptible to infrared contamination, even when the manufacturer attempts to reduce this problem by adding an infrared absorbing filter. Because these filters do not have a sharp cutoff at the infrared wavelengths there has to be a compromise in order not to exclude visible red wavelengths. This results in some infrared wavelengths being allowed to pass.
Denser grades of neutral density filters are more susceptible to this infrared contamination than milder grades and the effect is multiplied by the filter factor.