Seeing Red at 40 Meters (130 Feet)

One of my favorite dives was the last dive of my Deep Diving course. There wasn’t a wall at the dive site, so we swam out from the beach and headed straight out until we reached a depth of 40 meters.

Then I saw the color red.

As you can see above, this is what the color red looks like at 40 meters with a flashlight.

However, I did not have a flashlight with me.

Therefore, as you can see in the unlit image above, there is no way I saw the color red at a depth of 40 meters. That wavelength of light is absorbed by the water. Notwithstanding the impossibility of my observation, I nonetheless saw the color red at 40 meters.

I didn’t bring a camera on that dive, because I knew the available cameras would shut off at that depth. I also thought to show my instructor, but she was narced up and drifting away from me. I had no way to get her attention without sprinting over to her, which would’ve consumed alot of gas at that depth.

When we surfaced later, the first thing I told my instructor was that I had been so narced up I saw the color red at 40 meters. We both really enjoyed that dive actually. I then took the written test and completed my Deep Diving specialty.

Underwater Magic Trick

From left to right, these colors are red, orange, yellow, green, blue, and purple. Don’t believe me? Shine a light on it!

Isn’t that incredible?

This was taken at almost 40 meters to show how much color we lose at that depth. Even with great visibility, we see so little without flashlights.

For readers who are unaware, colors (wavelengths of light) are absorbed by the water (I’m oversimplifying). Without flashlights, we lose the color red very quickly. The deeper we go, the more color we lose. Eventually everything seems greenish and bluish, and eventually everything seems only bluish.

This is why so many photos online and on social media are so greenish and bluish. The colors have to be added back in with lighting, camera filters, or computer software.

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