A high volume mask is like a parasite to the freediver, sapping precious, life-giving air every time it needs equalized on descent. The primary feature divers look for in a mask is low volume. Low volume is to a mask what 4G is to the cell phone, what moist and chewy is to the cookie. It is an integral feature of a good mask. In fact, it's so important, I say let's go off the deep end (I wish I named my podcast that- "off the deep end"), and say "Why stop at low volume? Why not... no volume!"
How can you achieve "no volume?" How do you eliminate that parasitic airspace required for sight? The fluid goggle, that's how.
Fluid goggles use special lenses that allow you to flood the airspaces with water and still focus. Bye bye mask equalization, and as a side benefit, you can wear a nose clip, allowing for hands free equalization of your sinuses. Before we get too carried away, I should offer the disclaimer that you do sacrifice some clarity of vision. You can't see nearly as well as you could with a standard mask. But make no mistake, they're still awesome.
So where has this treasure been hiding all your life? Well, you could buy them online from LiquiVision or Martin Stepanek. I'm sure these are fine products, but what I would recommend is that you simply make your own.
You will need a pair of goggles, of course, and the lenses. The lenses you need should be 20mm focal length. The ones I got are medical grade 20x20 lenses from Anchor Optics. They are part number 23086.
Then you just need to mount them in the goggles. Put on your goggles and have someone mark where your pupils (use dry erase or a grease pencil) are centered so you know where to place the lens. I epoxied some acrylic tubing with 20mm ID onto the goggles and slid the lens right in. I used a pair of goggles I already had, but they eye pieces were a little small and I wasn't able to center the lenses, but they still work pretty well... at all depths without equalization!
