The Deep Black and White filter (850nm) The 850nm infrared conversion is good for a dedicated black and white IR. The camera and will produce bright whites and pronounced darks. With a custom white balance in camera, the picture is close to pure B+W without any processing. Equivalent to the Wratten 87c.
When to get this infrared conversion: This filter is the best for the highest contrast B+W, closest resembling traditional B+W IR film. Also good for forensics and other applications where the deep IR wavelengths are helpful.