Mask that doesn't magnify things underwater?

[fuzzybabybunny]

Are there any masks with lenses that undo the effects of index of refraction such that things look their natural size underwater rather than larger?

 

[caruso]

No because it's not the mask, its the difference in the index of refraction between water and air that makes objects seem larger. It would theoretically be possible to design a lens with minus power such as for nearsighted people however if you didn't need that vision correction things would be blurred and you'd probably get a massive headache after using it.

The way I see it (pun intended) I'd rather things seem bigger anyway. It's more exciting.

 

[runsongas]

hydrooptix is negative diopter and you use contact lenses if you are 20/20 to basically make you nearsighted and then the mask corrects on top of that.

 

[caruso]

hydrooptix is negative diopter and you use contact lenses if you are 20/20 to basically make you nearsighted and then the mask corrects on top of that.

You almost have it. The no longer manufactured hydroptix mask has built in minus power or negative diopers, so a diver will effectively become farsighted while wearing it if they are emmetropic (no refractive error). A diver in the low end of the nearsightness range will probably need no further correction when wearing this lens to see clearly and not experience the headaches and near vision blur due to the minus power of the lens, other divers will need to wear contact lenses that correct farsightedness (positive diopters) to offset the negative power of the mask especially divers who are 40 years of age and older and obviously divers who are farsighted to begin with.