Athena Extension Ring 60 with Focus Knob (Sea&Sea DX/NX Mount)

Athena Extension Ring 60 with Focus Knob, provides manual focus for compatible zoom lenses.

Compatible Housings:

• MDX series housings.

Compatible Lenses:

• Canon EF 16-35mm F2.8L ll USM (Optional Athena FG/16-35c-A focus gear required)
• Canon EF17-40mm F4L USM (Optional Athena FG/17-40c-A focus gear required)
• Nikon AF-S Zoom-Nikkor 14-24mm f/2.8G ED (Optional Athena FG/14-24n-A focus gear required)

* Compatible focus gear required for manual focusing (can be used in conjunction with a compatible zoom gear).

* Until now, auto focus has been the only option available when using a zoom gear. With the Extension Ring 60 with Focus Knob, you can now manually focus a compatible zoom lens. When your camera's AF frames do not cover your subject, you can manually focus a compatible lens without changing composition.
* This product is the ideal solution when you shoot fast-moving subjects (which even the latest auto focus may not follow) or when you shoot in dark environments and when there are lots of particles suspended in the water; all situations where auto focus will