The optional Wide Angle Port M67 for Isotta housing Canon G5X can be
used in place of the housing's standard port for use of 67mm threaded
external wide angle lenses. This port is as close to the camera's lens
as possible for the best image quality and very little vignetting (dark
shadows in the corners of the image) with external wet lenses. Vignetting can be eliminated by cropping the photo in post-production.
The INON UWL-H100 exhibits the least vignetting and best clarity with
this model among popular wet lenses currently available on the market.
The standard lens port is removed and the Wide Angle Port M67 simply
threads into the front of the housing for quick and easy installation.
The camera's focal length must be pre-set to 25mm whenever this port is
attached and cannot be zoomed underwater behind this port.