Underwater camera setup

SafariBob wrote:

i often don’t dive at all or if I do it may be 2-5 dives

so you'd literally spend more time setting up the camera than actually using it on air.

$400 doesn't even get me a macro port, nevermind the macro lens or the housing.

seafrogs?

Someone here suggested their dome ports were not great.  No personal knowledge.  Macro, otoh, is fairly simple: flat piece of glass.  If you're mostly snorkeling, you can probably skip the expense of the focusing knob and the focus gear - I'd be super impressed at the free diver who can linger long enough to actually do a manual focus on a 1-2" object.

Having your body only gets you 20% of the way. Do you have suitable lenses - Sony is not the best player for UW in this regard. Doesn't have a true fisheye, not that many topside shooters would have one, and same is true for that macro.

i have the 16-35 and I am ok with getting the 90mm. May swap the 16-35 for the 12-24 if I can find more use cases for wide angle.

As I alluded to above, macro is a challenge on breathold, esp with a FF sensor.   With my 4/3rds, I was fine with camera focus, though small stuff was still a battle if it were moving, or if there is current.   With the FF, I have made 7 or 8 dives and I had to buy the manual focus implements.  The DoF is just too narrow.  (I'm also still struggling to get the macro setup properly neutral, like my WA setups).

Shooting a rectalinear lens like the 16-35 requires you to go big on the dome - ideally 8 as a minimum.  The 6 can suffice for the 4/3 or the APC.   With the FF I think you'll see issues on the edges.

The fisheye is usually a better lens for WA, lets you/forces you to get within a foot of your primary subject and still show a lot more angle than the 16-35 will.   This can work with a 4.33" dome, which packs better, though it's still fine with the larger dome.

I think your best bet is to just pick a single lens - likely the 16-35 you already own and just stick to it initially.

where can I buy used?

wetpixel, scuba board are the largest sources.   Some action on ebay, though less than they're used to be.  Backscatter used to sell consignment, but don't appear to any more.

could be, but I am willing to take the chance. I am fairly experienced photographer, so I think with enough snorkeling experience I might be able to handle it

most of that experience doesn't translate well.  The control surface is radically different, the weight/buoyancy is very different, and the composition rules and lighting requirements are equally foreign.

it's easy to hold your breathe to take the shot of the cheetah.   But UW, that CO2 reflex is demanding you surface soon.  You can't linger in the shooting position either.   And your LED lights will give away your presence.