glueing reading lenses in mask

[dave4868]

Dave, there's a problem here. Magnifiers depend on the difference between the refractive index of air and the glass. If you wear them outside of your mask they're strength is greatly reduced because of the refractive index of the water that they're in contact with. They work much better if worn inside the mask.

Wes Pratt, a shark biologist I worked with some years ago spent a great deal of time designing and building a working underwater magnifying glass.

People have been glueing reading glass lenses into masks for many, many, years and that works well, as do the little gauge readers.

Thanks! That would explain why the "350" strength seems to be about right for me under water, when I would normally use "225" in air.

With the 350's on the outside of my mask, I can see my gauges clearly about 18 inches away. Without them, my arm isn't long enough.

It is kinda nice having them out of view until needed, another plus for flipping them up.

They're inexpensive, too. (Yep, cheap counts with me.)

By the way, do you remember any of the details of the underwater magnifying glass design? Anything interesting?

Dave C

 

[CMAN]

I use these http://www.walgreens.com/brandstore...ME=Optx-20/20&navAction=jump&selectedBrand=19 in my mask (Cressi Horizon) and they work great. You do have to wash the mask lens real good and let it dry overnight before applying the lens with water. They stick to the inside of the mask and stay on even when using "no fog". Mine usually last about 20-30 dives before I have to peel it off (I only us one lens for reading gauges or camera) and re-do it.

 

[dlndavid]

Somebody here on SB gave me this company awhile ago...if you order 10 or more pairs they are less than eight dollars a pair, which means who cares if you lose one once in awhile!

free shipping on orders of 100 dollars or more...you can use them in masks too.

http://order.store.yahoo.net/cgi-bi..._lToXthOz6nv6KpWhu9CPjLFDf3z4HK0bmkOStvTnPQ--

I put them in about six pairs of sunglasses, one of which are usually on my head, and I don't have to fuss with reading glasses, they are always handy! It has made my life much easier.

Catherine, we have stores out here called Dollar Tree, they sell the reading glasses for $1, want me to send you some?

And Lynne, Silicone at the base of the lens is what I want to try

 

[cmalinowski]

I use these http://www.walgreens.com/brandstore...ME=Optx-20/20&navAction=jump&selectedBrand=19 in my mask (Cressi Horizon) and they work great. You do have to wash the mask lens real good and let it dry overnight before applying the lens with water. They stick to the inside of the mask and stay on even when using "no fog". Mine usually last about 20-30 dives before I have to peel it off (I only us one lens for reading gauges or camera) and re-do it.

Link didn't work for me.
Chris

 

[dlndavid]

me neither, tryed some searches couldn't find what he was reffering to

 

[jimbo2006]

I searched Walgreens for "stick on magnifying lens" and found what others had mentioend. Paste this link into your browser if it doesn't work within this reply.

http://www.walgreens.com/store/product.jsp?CATID=305415&navAction=jump&navCount=0&id=prod1442732

The product name is apparently "Optx-20/20 Stick-On Magnifying Lenses

 

[cmalinowski]

I searched Walgreens for "stick on magnifying lens" and found what others had mentioend. Paste this link into your browser if it doesn't work within this reply.

http://www.walgreens.com/store/product.jsp?CATID=305415&navAction=jump&navCount=0&id=prod1442732

The product name is apparently "Optx-20/20 Stick-On Magnifying Lenses

worked. thanks.

 

[divad]

Walgreens, that's the ticket.

 

[CMAN]

try this link http://www.walgreens.com/search/search_results.jsp?_dyncharset=ASCII&term=stick-on lens

 

[dlndavid]

sweet, I'll try these out, great information, thanks