Dry lens for underwater use

I have tested and used this for some time

http://www.ebay.com/itm/XPRO-F500-67mm-Close-Up-Lens-Macro-lens-Super-Macro-Conversion-Lens-/280874520769?pt=Camera_Filters&hash=item41656d10c1

mostly using the 49mm on my Nex camera lenses.

Images:

http://images5.fotop.net/albums7/herbridge/Sipadan_2013/DSC2238.jpg

I wonder if this can be used underwater

I don't know if it will fit in the housing, but if it does then it will work pretty much the same UW as on land. If you mean putting it on the outside of the housing then you will get much less magnification with it if it is wet.

Bill

Did you try this dry diopter underwater? As a wet lens? I would think it being a achromatic double lens, water seeping into places becomes an issue, especially between the space between the lenses. I would think a single lens, even with its inferior image quality, would last longer as a wet lens.