Certain mask manufacturers offer a limited range of replacement ‘corrective’ lenses, which actually fill the entire lens aperture. However, as these come in a limited range of prescriptions, go in half dioptre, as opposed to quarter dioptre, increments and make no correction for astigmatism ( the Cyl. Part of a prescription ), they are only suitable for a small percentage of people.

 

It’s a bit like buying ‘off the peg’ clothes… If you are lucky enough to have a prescription of, for example, +2.50 right eye sphere and -1.00 left eye sphere, there will be dive-shop lenses that ‘fit’ you perfectly.

 

However, if your right prescription contains figures like -2.25 Sph. with -1.25 Cyl. an Axis of 135 and a +2.25 add, you are going to need precise ‘made to measure’ lenses. Moreover, as sight4sport is run by a qualified optometrist, you can be confident that Dive-Vision will give you the best advice and that the prescription is correct and the lenses are set to your optical centres (inter-Pupilliary Distance ), an important factor in giving you optimum underwater vision. We are also able to advise and cater for very high corrections ( above +/-10.00 Sphere and 4.00 Cyl ) and to allow for prism, where applicable.

No reason whatsoever… except, of course, for a little protozoa, called Acanthamoeba. This lives in both salt and freshwater and can cause Acanthamoeba Keratitis, which is an infection of the cornea - the front part of the eye. This is a painful, sometimes permanently damaging condition which can result in a corneal graft… or even the loss of an eye! A contaminated contact lens greatly increases this risk.

Secondly, if your mask floods, there is the risk of a contact lens being displaced… which is inconvenient to say the very least. But this can have an even more serious outcome… The higher osmolarity of seawater, or lower osmolarity of freshwater, when compared to tears, can cause soft contact lenses to adhere to the eyes. To ‘unstick’ them will require irrigation with isotonic saline, something that is not readily available on most beaches or dive sites!

Soft contact lenses can also absorb proprietary ‘de-fogging’ solutions, which can cause eye irritation. Another good reason not to wear them.

Last but not least, some divers who wear hard or gas-permeable contact lenses, can experience blurred vision after diving. This is because gas is under pressure in the mask, causing the tears to absorb nitrogen. When the diver surfaces at a normal rate, the tears and cornea are unable to eliminate the inert gas as quickly as they would without the contact lenses in place, causing bubbles to form between the lenses and cornea, which will affect the surface of the cornea, causing the blurring.

Yes. There is also an effect of the lens in the mask being further from the eye than in your spectacles. Some of these factor enhance and some detract form the effects of the prescription lenses but vary according to water conditions or environmental and the type of prescription.

This is a question we try to avoid answering, purely because the fit and feel of a mask is such a personal thing. All faces are different, all masks are different and one person’s favourite is another person’s pet hate. All the masks we show on our website are good quality, known brands, from reputable companies. We can tell you which ones are ordered most often and we can tell you what other people say about them… but we cannot make a firm recommendation as to which you should buy.

As a general rule, all the masks shown on our website are suitable for the majority of prescriptions. The only exception to this relates to masks described as ‘Low Volume’, which are not recommended for higher prescriptions – especially with plus correction. This is because the thickness of the lenses ( at the centre with plus correction and at the edges with minus prescriptions ), will tend to place the glass too close to the eyelashes, which can prove very aggravating to the user.

Sorry, there are no varifocal lenses available for dive masks, not from us or anyone else. Again, this is simply because there are no flat-fronted, lens blanks made that would enable us to do this.

However, we can supply bifocals… in fact, they probably account for some 50% of all the orders we receive. These look like one single piece of glass, with a small, virtually indiscernible, 28mm reading segment at the bottom. This segment is well out of line of sight when you are swimming ahead, but positioned to be exactly in line of sight when you want to read your computer or gauges, check camera settings or look at anything up close. ( To see what these look like, Click here )

We carefully set the height of the top of the segment depending on the make and model of mask. However, we can vary this for specific applications, such as photography, where we can, for example, provide a much larger read area if required.

The lenses, which are made from high-quality optical glass, are permanently UV bonded to the inside surface of the mask’s original, plain ( plano ) glass faceplates. Unlike the self-adhesive lenses that are available over the counter, our lenses will not come off.

The short answer is 'No'. This isn't a failing on our part, nobody can. There are no flat-fronted, corrective lens blanks made that are large enough to fit the entire lens aperture of any dive mask.

 

If there were, the edge thickness of higher correction minus lenses and the centre thickness of plus lenses, would make the lenses very heavy.

 

We endeavour to make the lenses as thin and light as we possibly can, for any given prescription.

 

Some mask manufacturers do supply replacement, corrective lenses, "off the shelf". These are often for minus corrections only, they make no correction for astigmatism ( Cyl.) and are only available in half, as opposed to quarter dioptre increments. As specialists in 'precise prescription' glazing... exactly the same as the prescription in your everyday glasses or contact lenses, we do not supply 'off the shelf' lenses. Moreover, many masks do not have removable lenses.

We’ll give your friend a 10% discount straight away!

Sure. We’ll give you 15% off your second mask and a further 20%off any other mask you buy from us.

No problem. When we heat the lenses in an oven to extreme temperatures they can be removed and new lenses put into the mask.

There is a charge for the new lens and fitting.

Yes you can and there’s no need to use toothpaste the first time you use your mask as coating will have been removed.

Delivery costs are around $25.00 USD to anywhere in the world and all deliveries are sent by recorded delivery and are insured to the value of the mask.

NEVER! They have been tested through boiling, freezing, immersed in several different chemical substances and they have never come off unless we have wanted to take them off which is a process they will never go through in your hands.
We guarantee them for life.

Normally, it’s the face plate that breaks and not the lens so send us the pieces, we’ll remove the lens, check it and after polishing, we’ll replace it. However, you will have to replace your mask if it is full face plate.

We can glaze any prescription.
Some powers are Standard Range, others fall in to High Prescription (HP) but we have glazed powers from + 20.00 to – 15.00.

From experience we know the best position in all of the popular masks on the market.

1)    Bifocal height is set ergonomically to suit the head position when diving.
2)    Photographers need a high bifocal to read details from the camera.
3)    We have to match the centres of the lenses to the distance between your pupils, for the best vision, to prevent visual discomfort and to produce the most suitable lens thickness. High powered lenses may need higher volume masks.
4)    Call us if you want to send us your own mask and we’ll go through the process with you.

1)    The power of the lenses, from the prescription given to you by your Optometrist/Eye Doctor/Optician.
2)    The distance between your pupils. This helps us set up the lenses to give you the best vision and prevent any unwanted effects on the power.
3)    If you have any particular special needs when diving e.g. Photography, interest in small marine life etc. We can make adjustments to the prescription.
4)    If you are over 45 you may need a reading only segment or bifocals to clearly see your gauges or computer, as the muscles in your eyes make near vision more difficult………`your arms aren`t long enough!

Most people have a degree of astigmatism and this can’t be corrected with an `off the shelf` lens. It means that your eye has 2 curves which need correcting (like a rugby ball shape) rather than one curve (like a soccer ball). The curves are at a particular angle (`axis` in your prescription) and this is individually set when glazing your mask.

You can have a full distance prescription, a small reading segment in the lower portion of the face plate, or bifocals. There are no varifocal lenses available for fitting to dive masks.

YES! We can put any prescription in any mask. Just choose one of the masks from our site, let us know your exact prescription and we’ll get it done for you.

Or you can even send us your own dive mask and we’ll put your prescription in it although this will take a little longer because of having to post your mask to us.

They come in a very limited range of + and powers and most people require an astigmatic correction and `off the shelf cannot correct this, so the quality of your vision through the mask is reduced.

There is a great risk of infection and you are quite likely to displace a lens when diving, causing discomfort and visual problems.

You will see as well as you do with your glasses, making you more aware and able to enjoy a safer, more environmentally friendly dive.