The MidOpt DB475_850-40.5 dual bandpass filter has been primarily designed for NDVI imaging applications. When using a single camera, this filter allows reflected near-infrared light (850nm) to be captured in the red channel and reflected blue light (475nm) to be captured in the blue channel (the green channel is not used). Even with an inexpensive consumer camera (that has had its IR-blocking filter removed), this easy separation makes it possible to post-process the red and blue channels for NDVI by performing the calculation: NDVI = (red – blue) / (red + blue). Healthy vegetation will absorb (not reflect) blue light and strongly reflect near-infrared light. Thus, this information can be used to apply a false-color gradient to images to better highlight the contrast between healthy vegetation and areas with stressed/diseased or no vegetation. All MidOpt filters can also be purchased unmounted or in custom dimensions upon request from Machine Vision Direct. Technical Specifications Specifications + Useful Range Min 460 nm Useful Range Max 490 nm Secondary Useful Range Min 830 nm Secondary Useful Range Max 870 nm FWHM 4560 nm Adhesive Backed Yes Tolerance 5 % Peak Transmission ≤ 90 % Surface Quality (Scratch-Dig) 40-20 Substrate Material Clear Glass Filter Diameter M40.5 x P0.5 Product Availability + Standard Lead Time 15 Days Stock Location Built to Order Product Lifecycle Active
