The optional Wide Angle Port M67 for Panasonic ZS100 TZ100 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.