Materials and construction
The favoured material for most modern masks is silicone, a non-allergenic material which resists deterioration. Frames and buckles are usually made from a hard plastic, which is lighter, less costly and offers longer mask life than using metal components. Many masks now come with a double-flanged face seal. This is a second sealing surface that increases the air and watertight properties of the mask.
Most manufacturers label their masks to indicate suitability for small, medium or large faces. Larger masks are especially suitable for fitting over beards, while masks designed for smaller faces are especially suitable for women.You will also see reference to the ‘volume’ of a mask. Low-volume masks are designed to place the lenses closer to your eyes, making low-volume masks ideal for those who enjoy underwater photography, as it places the view-finder closer to the eye. Low-volume masks also give better peripheral vision, decreased distortion and enhanced light transmission and the decreased bulk also gives less resistance through the water. However, prescriptions with higher plus (+) or minus (-) values ( see About eyesight or About lenses ) can mean that low-volume masks are unsuitable, as the lens thickness will position the lenses too close to the eyes or facial features. DiveVision makes every effort to indicate the size and suitability of every mask as accurately as possible.
Field of vision
Virtually all modern masks give a good field of view. Masks with ‘side windows’ give improved horizontal view out of the water and the image size through the front and side plates will be similar. However, the refractive effect under water can give problems, as the image through the corrective front lenses and plain side lenses will appear very different, both in terms of size and position... Choose your mask carefully. If you are unhappy with your purchase, we will take it back and refund the cost of the mask, but we cannot reimburse you for the cost of glazing as the lenses we fit will be to your specific, personal prescription and the mask cannot be offered for resale with these lenses fitted. ( See Conditions of Sale )