I have a Sony A7Riii on pre-order and am trying to nail down everything I'll need for my underwater setup. I've been shooting an RX100v1 for the last few years. It's served me very well, but I'm finding myself more and more frustrated with soft corners in wide angle, as well as really slow strobe recycle time. Watching your subject swim away while you mash the shutter and curse at the lack of strobe power settings in the camera is getting really old.
Last year I rented an A7Rii setup with the 90mm macro, and the 28mm prime with fisheye adapter for a one week liveaboard in the Caymans. I really liked the system. The flash trigger is AMAZING! Compared to the internal flash on my RX100 getting a few frames/sec out of this was a huge improvement. It also takes incredible hi res pictures that were very sharp. Almost too high res, I ended up with nearly 200GB of photos in one week of shooting. I had to do some serious culling when I got home.
There were a few things holding me back from getting one of my own. Battery life was my number one issue, especially shooting macro. After a single dive, I would come back with 50-60% battery depending on what focusing mode I was using. I could probably get two dives out of a battery, but I ended up swapping it out most dives just in case something great happened on the next dive. Focusing was also not as fast as I wanted. It was definitely an improvement over my compact camera, but for the kind of investment I was looking at, it didn't seem like enough.
Enter the A7Riii. Based on the pre-release hype, it looks like Sony has improved on my two biggest complaints. The new camera looks really great, and I think I'm finally ready to pull the trigger. I realize that the housings for this haven't even been officially announced yet, but I'm daydreaming about it, and want to be sure I'm ready to get the right gear once it becomes available.
I already picked up the 90mm macro lens, and have some wet diopters that I'll use with it. I'm happy with the great image quality this lens delivers, and am hoping that the improved focus of the A7Riii will reduce the occasional hunting that I saw with this lens on my rental.
I'm not so sure about my wide angle options though. I've searched the forums, but it seems like most of the posts are from near the A7Rii release, and there are a few more lenses on the market now. The 28mm prime with fisheye adapter worked fine on my rental and I missed the ability to zoom a lot less than I expected, but it looks like there are better options out there now. Looking at the Nauticam port charts for the A9, it looks like if I wanted to use the 12-24mm fisheye, I would need to go with the 230mm dome port. It looks like I can use the 230mm port with both Sony 16-35 lenses as well, but if I rule out the 12-24 fisheye I could get away with a smaller port. The 28mm lens with WWL-1 wet lens looks like an interesting choice too for a small, travel friendly option.
I'm leaning towards just grabbing the 12-24mm fisheye and larger dome and being done with it. I'm looking for maximum corner sharpness, and my understanding is the bigger the dome the better. I'm also leaning towards the wider lens as with 42mp on the new camera I should be able to crop as needed if things end up too wide. Does anyone have the weight difference between the two domes? I'm seeing 2.63kg for the larger one, but not finding consistent answers for the smaller.
Any idea of the real world difference between the 12-24 vs either of the 16-35 lenses underwater? Any reason to pick the expensive F2.8 16-35 over the F4? Do I really need the F2.8 if I'm going to be shooting F8 or higher all the time anyways with the dome port? Will the 16-35 lenses perform well under the larger dome, or with them not being fisheye lenses will they work better with the smaller one? Any thoughts on using adapted Canon lenses? As I'm new to ILCs I don't have any old glass to try and adapt. I'm guessing I'd be better off sticking with Sony. Any reason to consider the WWL-1 option other than cost/weight savings?
The WACP from Nauticam also looks pretty impressive. Looking at preliminary pricing, unsure about availability, and the fact that no one seems to have tried it with Sony cameras yet is keeping it out of the running. Maybe next year. Any other must have accessories? I'm already in for the flash trigger and vacuum valve, but maybe there's something else that would improve my experience with Nauticam that I haven't considered?
I realize that neither the camera, or the housing are out yet. Hopefully someone will have some input based on their A7Rii or A9 experience. Sorry for the wall of text... I was actually quite surprised to not see any mention of the new camera here already. Maybe it's just me that's excited? I used the RX100 for nearly five years, and expect to get a similar amount of time out of this setup so I want to be sure I get it right. Hopefully with some advice I can start collecting parts.