As water drop photography grew popularity, there has been many innovations about making water collide and splash. One such technique is the so called “Shoot From Below” setup. Basically, this technique utilizes pressurized or compressed air to push water jet up and then collide with water drop falling from above, the result can be astonishing.
Here is one example of Shoot From Below technique — yellow jets are shot from below with pressurized air tank and collide with red drops from above
This might sounds very expensive to do, but in actuality, it is not and it is safe, too.
The basic idea of this Shoot From Below technique is to use compressed air or pressurized tank to push liquid out of a container. Since I am a cautious person, I do not like high pressure equipment in my flat, I opted for a much safer one, a pressurized sprayer, commonly found in garden supply shops. These pressurized sprayers are cheap, easily modifiable and easy to use.
This is what I use, but you can use any types as long as it has the features outlined below. A – Inner outlet opening, B – Pump Handle, C – Lever, and D – upward going liquid
The above picture shows the one I am using, and there are a lot of similar devices sold around the world. You can use any pressurized sprayer you like provided that the tube you are going to use can fit tightly. For example, with this particular sprayer, you can unscrew a nozzle and expose its inner fitting. This inner fitting is just about 9mm, thus, using a silicone tube with 8mm inner diameter is perfect. So it is important to know if you can fit a silicone tube onto your pressurized sprayer when you purchase it.
It is also important that you use silicone type of tube because they are very elastic and usually it should have a smaller inner diameter than the sprayer’s fitting so that it will be very tight — this is important as pressure can break the connection easily if not tight enough and you end up a messy floor.
Because the pressurized sprayers are designed for spraying liquid, it is very handy to simply add the liquid you want inside the sprayer and connect its output to a valve which in turn is controlled by water drop controller. Another way to use it is to use it as a air pump and connect it to a water bottle holding the liquid you want to shoot up. Either configuration is fine but the first one is easier. However with second configuration, you can chain up multiple bottles with different colors and use the sprayer as common air pump. Sure it will be complicated, but you would only need one pump for multiple colors.So basically, it looks like the following:
Sprayer -> Silicone Tube -> Inlet of Valve -> Valve -> Outlet of Valve
Another consideration of Shoot From Below technique is the outlet nozzle of jet going up must be very small. Since these pressurized sprayers do not create very high pressure, normally up to about 15psi, it is critical of using a small opening for the jet going up. Otherwise, the jet will not be very tall and sometimes, the jet is not as straight as we would like. Larger opening of output nozzle usually suffer from wiggled jet (i.e. not smooth straight). So, it is recommended to have an opening with about 1mm to 1.5mm in diameter like the one below.
You can also use silicone tube to connect the outlet of valve to a three-way fitting or right angled fitting via yet another silicone tube like this:
Sprayer -> Silicone Tube -> Inset of Valve -> Valve -> Outlet -> Silicone Tube -> SFB nozzle.
This configuration allows you to submerge the final shoot up nozzle in liquid surface. This configuration makes it as if the jet is coming out of catching basin. Here is a picture of the three way fitting.
A – inlet of 3-way fitting, B – outlet of fitting for the smaller opening diameter nozzle, C – nozzle filled with hot glue to block it.
To conclude, here is a video about making a Shoot From Below kit.