The idea behind this outdoor campaign for Notankers is pretty unique, but the effectiveness is kind of questionable.
The reason I say that is, the amount of time you have to grab someones attention as they walk by a poster or sign is about two seconds on average. Linger time isn’t much longer, so your message has to be conveyed quickly and concisely. The end message that is shown after the ink washes away does that, but the time it takes to reveal the message probably won’t get people to stop. Especially if they are walking in the rain.
I like the idea, thinking, and execution here, I’m just not sure about the overall effectiveness, even when the posters are assembled in a long bank like they show in the video. I’d like to see how much traffic to their website actually increased after this campaign was run. I wouldn’t be surprised if the traffic spike occurred a couple of days after the ink had washed off, and the actual editorial message had a chance to sink in with passersby that frequent the area.