Getting Wine Glass Shaped Collision

When I first started water drop photography, I struggled a bit even though I designed my own water drop equipment. After figuring out how to get guaranteed collisions described in Guaranteed Water Drop Collision post, I wanted more. I accidentally stumble upon one shape that looks like wine glass and I liked it a lot.

It was illusive at first, I was not able to repeat it. But eventually, I figured it out.
Here are some wine glass shaped collisions that I can create repeatedly and consistently by following the steps below.

Step 1 — Set number of drops to one. Follow the instruction in Guaranteed Water Drop Collision so that the drop just hit the catching surface.

Step 2 — Adjust drop size to moderate value so that the Worthington jet it forms is very thick, but usually very short as shown in the first image in above picture. There is no need to take a picture, you can actually see the jet. Here is a tip: the larger the drop size, the taller and thinner the Worthington jet until certain point this will not be true.

Step 3 — Adjust Flash Delay value until the Worthington jet is peaking. At the same time, also adjust drop size describe in Step 2.

Step 4 — Set number of drops to two and set drop size of second drop to be about 10% to 15% bigger than the first drop.

Step 5 — Use the method in Guaranteed Water Drop Collision to get a collision. Adjust both Flash Delay and/or delay between the two drops.

Step 6 — Setting larger drop size of the second drop will probably result in “double” chin wine glass shape.

To conclude, essentially, to create a wine glass shaped collision is to use two large drops and short delay (but long enough to have a collision) between them.