 |
|||
 |
|||
 |
|
|
|
 |
||
|
|
|
 |
||
|
|
|
DSLR
Subal Port System
SUBAL complement their housings with an extensive
range of ports to suit different lenses. The line up includes
dome ports, flat ports and dedicated ports for Nikon micro
lenses. Currently, lenses from full frame fisheyes through
to 180mm macro lenses and many zooms can all be
accommodated. The exceptionally wide choice of lenses
available to Subal owners when combined with the facility
to control focus modes, including switching between
manual and AF functions, focus lock and manual focus
with zoom makes the Subal system the most professional
and versatile available.
Subal ports all feature optical glass lenses for the highest
possible image quality and for ease of cleaning. Most
ports feature delrin bodies to reduce weight. They mount
to the housing via a bayonet which ensures quick and
easy port changes and is very secure.
SUBAL complement their housings with an extensive range of ports to suit different lenses. The line up includes dome ports, flat ports and dedicated ports for Nikon micro lenses. Currently, lenses from full frame fisheyes through to 180mm macro lenses and many zooms can all be accommodated. The exceptionally wide choice of lenses available to Subal owners when combined with the facility to control focus modes, including switching between manual and AF functions, focus lock and manual focus with zoom makes the Subal system the most professional and versatile available.
Subal ports all feature optical glass lenses for the highest possible image quality and for ease of cleaning. Most ports feature delrin bodies to reduce weight. They mount to the housing via a bayonet which ensures quick and easy port changes and is very secure.
Dome ports
DOME ports are recommended for use with lenses wider than 35mm. They provide several benefits. Firstly, they improve sharpness and colour saturation with wide angle lenses. Secondly, they eliminate refraction so that the focal length of a lens virtually does not alter underwater. This means, for example, that a 24mm lens does not become a 28mm which would force you further back reducing image quality and colour saturation by making you shoot through more water. When shooting split level photographs you also avoid the subject changing size at the air/water interface which can be very disturbing with a human subject for example.
Choosing a dome
SUBAL offer three styles of dome port. The fisheye dome is the largest in the system. This works well with all lenses from a full frame fisheye to a standard 50mm including many zooms. If you use or plan to use fisheye lenses you will need this port. Other ports will cause vignetting with fisheyes. This port is also an excellent choice for split level photography because of the large and more easily controlled waterline.
The universal dome is a little smaller. It will not work with fisheyes but accepts lenses as wide as 18mm. It works very well with lenses through to a standard 50mm and with most zooms. This port also is a good choice for split level photography.
For lenses from 20mm through to 35mm and for many zooms, more compact domes are available. They usually restrict the user to a specific lens choice and are less easy to use for split level photography because the waterline is small.
Before choosing a dome it is worth thinking through how your photography may change and how that might affect your choice of lenses.
Correctors
DOME ports act like a lens underwater. In effect they produce a virtual image which is so close to the dome surface that most lenses cannot focus on it.To correct for this a +4 dioptre close up lens must be screwed onto the front of your lens. The only exception are full frame fisheyes