Entering the underwater world for the first time… what to expect.
So there you are at the dive centre ready to do your very first ocean dive. You have practically bathed in sunscreen and stand clutching your mask, snorkel and fins like a kid clutching his lunch box on the first day of school. You are excited, you are nervous, you feel like you are just about to BURST from anticipation because all night you have been dreaming about what it would be like once you get down there. Rest assured, we are here to give you a little sneak peek.
Oh, what big eyes you have…
Underwater objects that are near to you will seem 33% larger and 25% closer to you than they actually are. Keep this in mind next time when you are trying to reach for the buoy line. This might also make you believe that you are closer to your buddy than you actually are.
Because of how light gets absorbed and scattered by water you will probably lose some of the finer details, especially of objects further away. This also tend to make those objects in the distance look like they are even further away than they are.
What you see is not what you get
Perhaps you fell in love with the beautiful, vibrantly coloured coral that you saw on a documentary and you want to see it in real life. New divers are often disappointed when they see a coral reef for the first time, thinking that it would be as colourful as they saw on television. As you go deeper colours start to fade until everything looks blue/green. This is called the Tyndall effect. Camera equipment have special settings and light filters (often red) to compensate for the change in light and colour.
With time you will learn the colour spectrum as you see it underwater and be able to identify different colour coral based on their subtle difference. Some divers dive with a flashlight on every dive to see the colour of the coral as you would see colour on land.
Everything isn’t always crystal clear
Once you get used to the feeling of your mask on your face you tend to forget about it and it becomes an extension of your body. That is, until either water leaks in or your mask keeps fogging up.
It is all around
Once you enter the water you will soon realise that things can occur all over, not only can you have your buddy in front, next to or behind you but they can also be underneath or above you. Spotting marine life becomes a bit of a treasure hunt as they often hide in crevices, under rocks or coral and can even pass directly above you!
Because you spend most of your dive horizontal in a space with less gravity than on land you might find that things are not where you would expect them to be. The power inflator hose for you BCD might be floating by your left year for example (if you didn’t strap it down).
When looking and feeling becomes touching
In an environment where touching is discouraged we often use our eyes as a substitute to touch. We can see when something might feel soft and squishy (like bubble coral or sea cucumbers) or hard and spikey (like stag horn coral or sea urchins).
Besides touching with your hands, your body comes into contact with many different stimuli, you become aware of the change in water temperature and pressure, the wetsuit on the skin it covers and the movement of water against your exposed skin, and even the salt water that might sting your eyes.
Eventually divers become so accustom to touching through seeing that it feels almost alien when they do touch something (like accidentally drifting into a rock or your buddy).
Increased pressure
When you are underwater you feel free and weightless. This is because water is denser than air and thus it supports your weight more than air does. As the water ‘holds’ you it enables you to move freely in all directions.
The other effect that this increased density has on your body has to do with the pressure that it exerts on your body and airspaces. Unlike on land, divers experience pressure changes constantly. Moving only a meter deeper or shallower will influence how much pressure is around you and whether you will need to equalise or adjust your BCD. With experience you will learn to adjust your position in the water by making small adjustments to the volume of your lungs.
Hearing
Sound waves travel much faster under water than in air. This results in sound seeming to be coming from nowhere or everywhere. It can often confuse and disorientate you as you cannot tell where it is coming from.
As external sounds drift to the background you become more aware of the noises your body makes. Breathing in-and-out through your regulator makes you sound a bit like Darth Vader blowing bubbles in his milk. You no longer hear your bodily sounds through the air but rather through vibrations in your bones. You might become aware of the sound you make when you swallow and the slight ticking that occurs when you equalise your ears.
Now you know a little more about what to expect from your environment, go and blow some bubbles and enjoy looking at those fish you little mermaid, you!
*This post was first published at www.scubadiverlife.com
