Question: Why are 'low volume' masks better than 'high volume' masks?

[mastakebob]

Something I've always been curious about:

In SCUBA diving, why is 'low volume' considered a selling point for masks?

The only benefit I can think of is that they take less air to equalize and/or clear. But the difference between the amount of air needed to equalize a low volume mask and a high volume mask has to be trivial, right? Over the course of a dive, maybe a few seconds of air time? I can see this being crucial in something like free-diving, but not in SCUBA.

I would think that the differences in hydrodynamics of a low volume vs high volume mask is about as trivial as the air consumption differences.

A definite con of the low volume mask is that when you get water in your mask, it is that much closer to your eyes/nostrils, increasing the chances of irritation during the dive.

What am I missing? Is it an optics thing?

Thanks for any insight!

-Kevin

 

[Bubbletrubble]

It's not an equalization issue.
It's possible that the optics are slightly better with less air between one's eyes and the underwater world.

In my opinion, the answer to your question is...
For a completely flooded mask, it simply takes less air to clear a "low volume" mask (vs. a "high volume" one).
It's a convenience thing more than anything else.

 

[driftwood]

Have to agree with the man from Seussville. When you find a mask that fits your face, low vs high volume isn't a big issue until you take a class where you frequently have to clear it.

 

[vladimir]

Having the glass closer to your face gives you a wider angle of view.

In strong current there is less mask "flapping in the breeze." I have seen a diver lose his mask to the current, and I've felt my own vibrate in a strong current.

Water doesn't pool in my mask when I dive; if it does I clear it. So water around the eyes or nostrils isn't an issue.

 

[Damselfish]

It's a bit easier to clear if it takes less air. Not a matter of using more air, but as said convenience.

It's a consideration in strong current. I've been in the occasional ripping current with the vibrating mask thing going on and higher profile would not have been a good thing.

For lenses of the same size - the closer to your eyes the lenses are, the wider your field of view is. You get a wider field of view without wearing a fishbowl on your face.


I don't really see any advantage to high profile. Maybe the same volume of water in a high profile mask won't come up as far, but I think the answer to that is to get a mask that doesn't leak, not to have more room for water!

 

[herman]

I agree with the rest, convience more than anything...and maybe some sale hype as well. On occasion I dive one of the old style oval mask which has a fairly large air space. It's no problem to clear but it does give me a little bit of tunnel vision, a little like looking down a short pipe. In any case, there is not enough difference to swap one over the other if you happen to like the larger volume one.

 

[miketsp]

Having the glass closer to your face gives you a wider angle of view.
..snip..

Except that most very low volume masks, of the type for spearfishing, use very small glass areas and black skirts anyway. So you still only see what is in front of you.

 

[Tortuga68]

Skirt colour isn't relevant

 

[MauiScubaSteve]

As is "de rigueur" if something is better for tech, or even one style tech, it must be better for all diving, no?

When a rebreather pilot without an O2 sensor clears the mask, it changes the O2 percentage of the breathing mixture. This makes the fuzzy math of the "inspired" gas calculation even fuzzier. The low volume mask is best for non 02 sensor rebreather divers who have to clear their mask.

For a free or breath hold diver, the low volume mask allows you to dive deeper, given everything else remains unchanged. The low volume mask is best for deep free diving.

The low volume mask that does not seal is not better for any kind of diving. The low volume mask is not necessarily better for typical recreational diving.

 

[Tortuga68]

The [-]low volume[/-] mask that does not seal is not better for any kind of diving

Fixed that for ya