The Science Behind GDome Dome Ports

Geometric functions of the GDOME PDS Dome Housings

With the expansion of underwater photography by both professional and amateur photographers it has increased the demand for a wide range of technical dive housing applications.

Demand has increased through the advancement of camera technology, diving apparatus and the availability of diving centres and submersibles. With the expansion of underwater exposure the expansion for underwater photography equipment and knowledge has been dramatic. Then underwater camera footage which was only accessible to professionals, in turn, is now available to recreational and amateur users.

The last few decades have pushed technology and development of underwater housings to new heights. Access to all the functionality of a camera used to differentiate professional equipment vs the amateur, today with the development of over the counter camera software has closed this gap considerably.

With market leaders GoPro leading the way with their product offering GDome saw the opportunity to bring a domed lens to the market at an affordable rate.

2015 was the start of our journey exploring the various housings offered and after months of product development we released our first dome housing. Why a dome housing and not a flat lens port? Here is why:

Refraction effects of light

Operating in a foreign environment has its challenges. When light hits water it causes its direction to change. The angle at which light hits water also has an impact. Both of these will determine the amount at which the light bends. Thus shooting in deep water or even the shallows, the changing environment affects the reflections of light, its absorptions levels and turbidity.

When light travels from air into water, it slows down, causing it to change direction slightly. This change of direction is called refraction. When light enters a more dense substance (higher refractive index), it ‘bends’ more towards the normal line.

As water is a different medium to shoot in, the following various considerations need to be taken:

1. Density of water is not as consistent through depth
2. Seawater is 800 times denser than air

Thus varying depths and conditions affect the optics of a camera and need to be altered and set up accordingly.

Flat lens / port

Today’s markets are flooded with a flat lens housings setup. From rigid to soft setups each have their pros and cons. Soft housings are subject to movement between the flat optic lens and the camera lens which may cause optical mishaps. Many rigid housings lack the functionality needed to adjust for the change in optics required when shooting in varying conditions.  Flat lenses have dominated the market because of the lesser cost of manufacture.

The field of view has also been a sore point as light has the chance to reflect even further between the optics lenses which struggle to handle the curving of light.

Characterizations of a dome port

To avoid the shortcomings of a flat lens dome lenses have been adopted. Thanks to the likes of GDome and other manufacturers this technology it solves the shortcomings of a flat lens.

Field of view and focal length of the camera's optics are preserved especially when dealing with wide angle lenses. The camera lens system attached to the dome port will focus on the virtual image produced by the dome port itself and not on the real image which is at a smaller distance than the object.

Taking all of this into consideration

From considering all of the information we researched and from our field testing the dome housings created for action cameras seemed to tick all of the boxes we intended on achieving. We were able to bring a market leading product to market at an affordable rate and ease of use anybody can use.

Result and developments

From releasing our first dome in 2015 we have made many advancements our customers have been very happy with. Our integrated seals, screws and backplate have made the GDOME unique. We have a passionate team who are geared at providing all of our dome users with the best dome and best customer experience.

After thorough testing of various lens sizes, heights and diameters, our PDS Dome Port Lenses are now a 6.1-inch diameter, which solves all of our points of consideration.

We found that by increasing the dome size radius from the industry standard of 4 – 5 inches to 6.1 inches offers:

1. A wider field of view
2. Better colour sharpness of images captured
3. Far less chromatic aberration (colour fringing)
4. Transferability of a standard lens across a wider camera range

Source: https://www.sciencelearn.org.nz/images/49-refraction-of-light-in-water