Artist who goes under the nickname of “smsilton” captured this amazing image after about two hours of attempts. All in all, he said that it probably took him about 150 shots to get it right.
The hardest part was focusing. In the set up picture you can see a piece of string above the eye dropper. I would let that hang down off the eye dropper and focus on that, then move it and squeeze the dropper and the shutter at almost the same time. I have like 30ish more pictures with the drop clearly in the shot but the sketch behind it isn’t in focus, this was the clearest one I got.”
Personally, I’d think the hardest part was being patient enough to shoot water drops for two hours just to get the one magical shot, but that’s why I’ve never had any interest in being a professional photographer.