through the Nikon F-Mount - Nikon SG-3IR - an inexpensive but very helpful accessory
D90 - light reflected with any sync speed below and including 1/200 in commander mode: Nikon DX SLR (D40-D90, D3000-D7500) Talk Forum: Digital Photography Review
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Nikon Filter Attachment SG-3IR - Foto Erhardt
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