When selecting prescription lenses for your underwater excursions, it's essential to ensure that your vision correction is optimized for the unique visual conditions you'll encounter beneath the surface. Our lenses come in increments of 0.5 diopters, which means sometimes we need to make a choice: should we round up or down from your adjusted prescription? Here’s a straightforward guide to help you make the best decision for your underwater needs.

Understanding the Need for Adjustment

Due to the magnifying properties of water, objects underwater will appear closer and larger. This effect means that your land-based prescription needs tweaking to give you the best possible vision underwater. Once we adjust your prescription based on our calculation (including compensations for astigmatism and the underwater environment), we might end up with a value that doesn't neatly fit into the 0.5 diopter increments of our lenses. This is where the decision to round up or down comes into play.

When to Round Down

Pros: Opting for a slightly weaker lens (rounding down) can make for a more comfortable experience, especially for general underwater activities or leisure diving where extreme precision isn't necessary. This option can help reduce the risk of eye strain, making it ideal for prolonged usage.

Ideal For: Divers and snorkelers who prioritize comfort and are engaged in activities where perfect visual acuity for every detail isn't a necessity.

When to Round Up

Pros: Choosing a slightly stronger lens (rounding up) is advisable for situations requiring sharp focus on detail. Whether it's for underwater photography or navigating intricate underwater landscapes, rounding up ensures that distant objects remain clear and well-defined.

Ideal For: Divers involved in activities where clarity and detail are paramount. This option ensures safety and enhances the overall underwater experience by providing the best possible visual acuity.

Making the Best Choice

The right choice often depends on your specific underwater activities and personal comfort. Here’s what we recommend:

General Use and Leisure: For most divers and snorkelers, rounding down might offer a more comfortable and convenient experience, leveraging the natural magnification effect of water to still provide clear vision.

High Precision Required: For tasks that demand sharp focus, consider rounding up to ensure that your vision is as clear as possible, enhancing both your performance and safety underwater.

Consult for Personalized Advice

We understand that everyone's vision and underwater activities are unique. For personalized advice, we recommend consulting with an eye care professional who has experience with underwater optics. They can provide tailored recommendations based on your specific needs and preferences.

Try Before You Dive

If possible, testing your lenses in a controlled underwater environment, like a swimming pool, can offer insights into which adjustment provides the best balance of clarity, comfort, and usability. This step ensures that you make the most informed decision for your underwater adventures.

Choosing the right prescription strength for your underwater lenses is crucial for a safe and enjoyable experience. By understanding the effects of water on vision and considering your specific needs, you can make an informed choice that enhances your underwater exploration. Dive in with clarity and confidence, knowing you've made the best choice for your eyes.