The Canon FA-DC58C adapter for the G1X has been criticized for being an expensive piece of plastic that should not even be necessary. That may be but it actually is necessary and therefore competition comes into consideration. Lensmate is a well known and respected third party manufacturer of components for Canon and other cameras.
I received my Lensmate filter adapter today; it is a nice looking, quality piece of machining. I also have the original Canon version. The Lensmate adapter is much more similar than different from the Canon adapter. The most obvious differences are that the Canon adapter is labeled “Canon” in white paint whereas the Lensmate adapter appears to be without a label. Also, the Lensmate adapter has a continuous knurl around the entire circumference whereas the knurl on the Canon adapter is interrupted. The Lensmate adapter is made from Delrin polymer whereas the Canon adapter is said to be made of ABS plastic.
The functionality of the Canon and Lensmate adapters appears to be identical. Both install with a 90 degree twist and both are threaded for 58mm filters. The Canon lens cap works with either the Canon adapter or the Lensmate adapter.
The Lensmate adapter has “LENSMATE FOR G1X” inscribed on the filter side. To install the adapter, position it so this inscription is at the top then twist the adapter clockwise (that is, “tighten”) 90 degrees. I admit to being a little uncomfortable putting a torque on the lens so I’m going to always install or remove the adapter before turning on the camera so that the lens is fully retracted during the process.
Although the Lensmate website appears to have installation instructions, the instructions have actually not been posted at this time. Also, no instructions were included with the product so, cowardly disclaimer:
The above “instructions” are my idea. Proceed at your own risk!.
The Lensmate adapter fits much tighter to the G1X than does the Canon adapter. In fact, at first I was hesitant to tighten the Lensmate adapter but after examining the fit, crossed my fingers (well, I would have, except, you know ...) and gave it a twist. I'm much more confident now and have had the adapter on and off several times. The Lensmate website appears to acknowledge that their adapter fits tighter.
At this point, I don't know which adapter I'm more likely to use -- probably does not matter but the Lensmate looks and feels a little better so I’ll be using it preferentially for now.