Nikon Z9 teaser #4: Zero blackout viewfinder, fast burst modes and another look at the 100-400mm F4.5-5.6 S lens

Nikon USA has released its fourth and final teaser in its ongoing series to promote its forthcoming Z9 mirrorless camera system. As we've seen with each of the three previous teasers, this one only hints at what we can expect rather than outright telling us. Nikon has also posted a countdown timer for its Z9 online launch event. In the 30-second video, we see a photographer with a Nikon Z9 in hand with the unreleased Nikkor Z 100-400mm F4.5-5.6 S lens attached. As he's shooting we hear what soun...