Grok say's about the ZB3 UV-IR filter. ZB3 UV-VIS Bandpass Filter – Designed for UV Precision & Stunning Full-Spectrum Photography. What the ZB3 Was Designed For. Unlike standard UV/IR cut filters, this bandpass filter selectively allows UV and specific visible light to pass while blocking infrared and most other visible wavelengths, giving it a “nearly black” appearance.
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