Mask and corrective lenses. Pls help

[blues_diver]

Hi

I have been searching the Board but seems to be getting conflicting answers on the use of corrective lenses for near-sightedness (myopia). Assuming that I have a negative diopter -5.0 for my glasses, there seems to be 2 different suggestions on the strength of corrective lenses for the mask:

1. Use lenses that are 10% stronger that is -5.5

2. Use lenses that are weaker due to magnifying effect when underwater.

Please help on which is correct suggestion. Getting confused after reading so many threads

Thanks!!!

 

[fdog]

I am nearsighted and wear my contacts under my mask; no corrective lenses built into the mask.

No issues and very convenient for me. Aviods the hassle of figuring out the scrip for my mask.

All the best, James

 

[Marek K]

I understand your confusion. I'm not going to advise you, just tell you about my experience.

I've got -9.5 diopter spherical correction lenses in both sides of my mask, even though I have a fair bit of astigmatism too. That's about 1/4 diopter weaker than my theoretical correction, but just about the same as my actual prescription for glasses (except for the astigmatism).
In the air, I can definitely see the lack of astigmatism correction. Underwater, I can't -- everything looks perfect.

My conclusion is that vision correction underwater is a lot more forgiving than in the air. Since off-the-shelf lenses are in 0.5-diopter steps, that's probably a good thing.

The dive shop where I got my off-the-shelf lenses promised to exchange them for free if they weren't right, after I tried them once in the pool... the 9.0's I got at first were noticeably too weak, and sure enough they exchanged them for the -9.5's.
--Marek

 

[diverberr]

The lenses in my mask are the same as my prescription: -4.25 in my left eye, -3.75 in the right. My lenses aren't the ones you can buy at the LDS, I had them done by my optician.

Al.

 

[Web Monkey]

I wear soft contacts for diving. They're cheap, work great and you can use any mask you want.

I tried getting lenses bonded to my mask, but ended up with tunnelvision.

Terry

Hi

I have been searching the Board but seems to be getting conflicting answers on the use of corrective lenses for near-sightedness (myopia). Assuming that I have a negative diopter -5.0 for my glasses, there seems to be 2 different suggestions on the strength of corrective lenses for the mask:


Thanks!!!

 

[blues_diver]

Thanks All for the prompt reply. Incredible SBoarders!

Unfortunately, I am one of those which cannot wear a contact lense and since I am still new, I don't want to spend too much on a "tailor-made" prescription mask....hence the off-the-self corrective lens route.

For your information, I have a -3.25 on my right eye and -2.75 on my left eye. Both eyes have minimal astigmatism (-0.50) and as Marek mentioned, this should not be problem when underwater.

As the mask I use, the corrective lenses come in increment of 0.5 diopter, I am now totally loss on whether to get a stronger one i.e. -3.5 and -3.0; or -3.00 and -2.50.

Any other comments/help will be appreciated.

Thanks!

 

[scubapro50]

I have always had bad eye sight and never found a "prescription" mask that I liked or had the required corrections needed for my vision. I buy a mask that really fits well that I like and have it sent off with a copy of my prescription to have lens made and then bonded to the inside of the faceplate. Your dive store should have of list of places that offer this service.

 

[Marek K]

For your information, I have a -3.25 on my right eye and -2.75 on my left eye. Both eyes have minimal astigmatism (-0.50) and as Marek mentioned, this should not be problem when underwater.

As the mask I use, the corrective lenses come in increment of 0.5 diopter, I am now totally loss on whether to get a stronger one i.e. -3.5 and -3.0; or -3.00 and -2.50.

Any other comments/help will be appreciated.

Thanks!

OK, since you insist on advice...

You're right, your astigmatism is so small that spherical lenses should work just fine.

In your correction, finding off-the-shelf lenses should be no problem. It becomes much more of a problem in high corrections, like mine.

You're lucky that off-the-shelf lenses are available for the mask you have. With four divers in our family, all needing corrective lenses, we haven't always had that luck.

In the case of your correction, a 1/4-diopter difference doesn't make much significant difference even in the air. I would round down, to -3.0 and -2.5.

--Marek

 

[Web Monkey]

Thanks All for the prompt reply. Incredible SBoarders!

Unfortunately, I am one of those which cannot wear a contact lense and since I am still new,
Thanks!

Still new what?

It doesn't take anything special to dive with a soft contact lens. It's only a little thicker than a piece of plastic wrap, and your optician usually has some free samples you can try.

Terry

 

[Marek K]

Still new what?

It doesn't take anything special to dive with a soft contact lens. It's only a little thicker than a piece of plastic wrap, and your optician usually has some free samples you can try.

Terry

There are people that can't wear contact lenses, or don't want to for whatever reason. Like if lenses -- even soft extended-wear ones -- don't let through enough oxygen for their eyes. Or if they're susceptible to infections. Or if they have such astigmatism that they can't get fitted right, like my wife. Or if they need bifocal correction, and don't want to use mono-vision, like me. Or, or, or.

And by saying he's "new," I think blues diver meant that he wasn't ready yet to invest in more-expensive prescription mask lenses that would perfectly correct his astigmatism. Which is good, because he doesn't have much astigmatism.

--Marek