I have been using a Seacam modified Nikonos R-UW 13mm with my D850 for about three years running now. So far, I have not found any wide-angle lens behind a dome port underwater to be anywhere close to its equal. Having looked at both Nauticam new FCP as well as their WACP C water contact lenses, they strike me as neither that compact, nor lightweight enough to make them as ideal for travel as my RS 13 setup.
That said, one of the primary setbacks with the Nikonos R-UW 13 is that the autofocus is driven by the earlier Nikon F screw drive system used in AF-D Type lenses up to 1987.
Back in November 2023, MonsterAdapter announced that it was developing a new LA-FE2 Nikon F mount to Sony E mount electronic lens adapter with both aperture and autofocus capability built in through a new dual motor that would also drive traditional Nikkor AF-D lenses. The new MonsterAdapter LA-FE2 was expected to be launched with price and more detailed information at the end of 2023, but as yet (Jan 22, 2024) it has yet to be seen.
My question is, if it had come be, would it have worked on my R-UW 13?
One the things that I have found with lenses modified by Seacam (perhaps my case only) is that the lens will not properly interface with my D850 with when I attempted to use it with the Kenko TELEPLUS HD Pro 1.4x DGX Teleconverter which is rated for Nikon AF-D types lens. Autofocus works, but nothing else. Just Error for Aperture, metering, and shutter.
Fortunately, I found no need to rush into the mirrorless camp as I see little outside of video capability providing any great advantage for shooting stills.
If I were to make the change to mirrorless, the most logical option at the moment for migrating that lens over would be to have the optics retro fitted into a Sony 50mm E mount mirrorless lens. This of course would be contingent on the modification would provide full functionality (correct aperture control and auto focus) with a E to Z adaptor on a Nikon Z8.
