The Formatt Hot Mirror/Neutral Density Infrared (IR) 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 photography, the sensitivity of imaging sensors to IR has become a challenge for both photographers, videographers and manufacturers.
Unlike many photographic films, the CCD or CMOS of a digital camera is inherently susceptible to infrared contamination, even when the manufacturer attempts to reduce this problem by adding an infrared absorbing filter on top of the image sensor. 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.
While minor infrared contamination does not normally cause much of a problem for visible images, when using conventional neutral density filters especially denser grades, this issue is multiplied by the filter factor.
High quality filter to prevent the color shift caused by the sensitivity of today's digital sensors
All Formatt filters are manufactured using Water White Schott optical glass that is precision polished and ground to ensure absolute optical flatness and optimum performance
Absorbing Cell Technology
The secret to Formatt's consistency in filter design lies in its unique "Absorbing Cell Technology" (A.C.T.); This unique process allows color correct dyes to be applied to optically pure, wafer thin absorbing cells and offers a controllability that ensures the smoothest grad lines and consistent color across the whole filter surface.
This process is revolutionary compared with conventional filter dying techniques by eliminating the need to directly coat the glass surface itself; The repeatable performance gained through A.C.T. ensures that at any time you have to swap like filters for like filters mid shoot you can do so with confidence with no discernable differences in color or density.
Each filter is guaranteed flatness to a maximum 2-wave value and comes with an individual reading from a laser interferometer; Every filter is carefully verified with a densitometer and spectrophotometer to ensure consistent and accurate transmission, before leaving the factory - the result is an absolute purity of image that eliminates any unwanted colorcast caused by conventional greenish soda-lime glass.
In the Box
Formatt Hitech 4 x 5.65" x3mm Hot Mirror/Neutral Density (ND) 0.9 Infrared (IR) Filter