Prescription Mask Off Focus Underwater

[lcollar]

I'm about to ditch my third prescription dive mask in six years and try contact lenses for underwater use. There have been 3 separate sets of prescription inserts professionally glued into 3 different quality masks. Two of these have come from an extremely popular/highly rated shop in Southern California. I see perfectly with these prescription masks above water so it isn't the shop or OD's fault. It has something to do with my eyes and the refractive power of sea water.

For some reason when submerged, the prescription is not correct and distant objects are not in clear focus. to complicate things even worse, I'm an older diver that is near-sighted so the prescription inserts have bifocals on the bottom of each lens so I can read my gauges.

My Optometrist is suggesting I try contact lenses or yet another reduced power (reduce by 2/3) prescription lens inserts to see if that will clear up my underwater image. I have chosen to try the contact lens but because of my extreme near-sightedness and the limitations of current contact lenses for bifocal use and lack of correction for astigmatism, I am essentially no better off in terms of visual correction - at least above water. By that I mean my distance vision is not as good as it should be and I suspect I'll have a hard time reading my gauge.

Here is my current presciption:

Sph Cyl Axis Add
OD -3.50 -1.00 02 +2.50
OS -2.00 -4.00 91 +2.50

Does anybody (preferably OD's) have an idea why this happens to me and what I should try next?

 

[MRadke]

I think the problem is squeeze.

I dive a fairly strong prescription mask. Mine is the Tilos Flex frameless with the optics ground for me and cemented in. What I have noticed is that unless I have the mask completely equalized, the vision isn't as perfect as it could be. I've not found a good defogger that doesn't fry my eyes, so I often tip a little water in the top of the mask, swish it around, and blow it out the bottom. The side benefit is that there is no squeeze effecting my vision.

Hope this helps.

 

[Doubler]

I see perfectly with these prescription masks above water so it isn't the shop or OD's fault. It has something to do with my eyes and the refractive power of sea water.

I believe the problem you are having is the prescription mask. Mine was made by Seavision out of Florida. I can't see a damn thing on the surface with mine but it is perfect underwater. Mine has the full glass prescription and not the Mr. Magoo glue in's. Seavision adjusts your prescription for the refraction. Give them a look or call them on the phone to discuss.

 

[Matt S.]

I got my RX mask direct from Atomic. I tried on Atomic masks in my LDS, found one I liked, and the shop sent my RX to the factory.

Vision out of the water is a little odd I guess, but it works fine when under. I'm pretty happy with it and would probably do the same thing again if I lost it.

Also, it was an eligible expense for my FSA, which was cool!

 

[H2Odyssey Rep]

Hello there! Looking at your RX you have a very high Astigmatism in your Left eye ( os) with such a high degree of Astigmatism or cyl things are not going to be "sharp" as they would be without it...Add to the fact that you need to compensate for light refraction (see an article I found for you, link: ) The Physics of Diving: Light and Vision I am not surprised you are having a tough time... I would take your Optometrist's advice, in your OS it is not the -2.0 that you would need to compensate 100 percent for it is the add that is more important, by dropping your RX by 2/3 this will give you the little "push" if you will to go along with what water naturally does and this should compensate enough while diving, keeping your ADD and CYL in your contact diving RX should help.. I would first experiment a little... Get in a pool, swim around with your left eye closed, see how your eye see's objects, is it fairly clear and can you read your gauges? Repeat the same with you Left eye right eye closed, what I would guess is that you are going to see that your right eye is better at seeing the "fuzzy" than your left; this is mostly due to your really high Astigmatism... Diving with contacts is extremely easy, just make sure to follow your Dr's care instructions and please get used to them really well before attempting to dive...You may find your above vision with them is not as good as your underwater, this would be because he has bumped your RX by 2/3 to compensate for the underwater world.... Hope this helps!

 

[SubMariner]

I see perfectly with these prescription masks above water so it isn't the shop or OD's fault. It has something to do with my eyes and the refractive power of sea water.

I believe the problem you are having is the prescription mask. Mine was made by Seavision out of Florida. I can't see a damn thing on the surface with mine but it is perfect underwater. Mine has the full glass prescription and not the Mr. Magoo glue in's. Seavision adjusts your prescription for the refraction. Give them a look or call them on the phone to discuss.

I would tend to agree. This is my 3rd prescription (bifocal no less!) from Seavision & I can't fault their lenses for u/w acuity.

Frankly, I don't know why anyone would opt to have lenses glued inside a mask when you can have properly ground optics that are corrected for use u/w.

JMHO,

 

[lcollar]

Thank you all for your comments and suggestions. I really appreciate the feedback and information source. I had the opportunity to try contact lenses for the first time underwater on Sunday. For those optical types out there the lens was an Air Optics. Right lens power was -3.50 with a +2.50 add so it was bifocal.

As the title above indicates, it was better at distance than any of my previous prescription masks but unfortunately it was horribly worse at distances less than 3 feet. 3 feet and out was good considering the vis on most of my dives this last weekend were 30' or less. After the second dive I popped the contacts out and put my old prescription mask back on. The close up vision with mask was hugely improved - enough for me to finally figure out what my camera was trying to tell me.

If I stick it out with contacts I'm thinking of going for a full power lens with astigmatism correction and put readers in my mask and have a pair handy on the deck when I get out. Does that sound like a viable option for me?

 

[H2Odyssey Rep]

The dr decided to keep you at full power? hummm...Try a trial pair where he drops the Add all together just going with your regular RX, if in a pool you can see sharply at a distance and cannot read your gauges then you will know for sure you can do full RX strength and just have gauge readers put in a mask...Again this is going to be fairly tough as your astigmatism is high...Try to never do glue in lenses as there will always be a pocket of air between the Rx and the mask from which will cause a bit of distortion to those that are sensitive such as your self... Lots of patience and trial and error is what it will take

 

[Doubler]

Cal Seavision! You'll be happier.

 

[lcollar]

Thanks again for all your posts on this subject. I did as you suggested and tried a full power trial pair of contacts in the pool last night without the add. I could see perfectly up to about 4 feet and less. Unfortunately I could only just make out the analog pressure gauge but nothing on my digital computer. I could focus my camera and that is a big part of why I set out on this journey to begin with.

Standing in the shallow end of the pool grousing about how badly I could see up close and watching the dive master on the pool deck trying to slip his size XXXL body into an XL dry-suit, he looked up and said, "you know we sell gauge readers?"

After trying on 4 different powers of these stick on readers, I finally found one that worked perfectly! Now I can see both near and far which is something I have been looking forward to for some time. The reader that worked best above water did not work well when I was submerged. The one that works best for me underwater is 1/2 a diopter stronger than my out of water prescription. I know there have been plenty of posts regarding these stick-on readers both pro and con. It certainly is a cheaper alternative to having yet another prescription mask made that may or may not work for me. Certainly worth trying and hopefully will give a framework for a more permanent solution.

We go to Monterey this weekend and hopefully the pool test will prove out in the ocean also.

I've learned a lot from those of you willing to chime in. Thanks again for all your own experiences and suggestions.