Barmaglot

Yes, I've bought stuff from them several times, including an Inon LF800-n torch that flooded on first dive - they replaced it; the replacement also flooded on first dive, then they checked the two remaining units they had in stock, and both flooded immediately. After that I had to wait for Inon to send them a new batch, but once they did, I got a working torch. That is to say, while their customer service is not responsive, they do exist and they do help when needed.

What, specifically, are you looking for? Do you have a preference between fisheye and rectilinear wide? Do you need zoom capability? The most common options with A7R series are: Fisheye - Canon 8-15mm f/4 on a Metabones or MC-11 adapter, optionally with a 1.4x or 2x teleconverter. This will work with a small dome and give you the widest FoV, but at the cost of fisheye distortion, which may or may not be a plus. Rectilinear - Sony 16-35mm or 12-24mm (there are multiple options for either) or, more recently, Tamron 17-28mm. This will keep straight lines straight, but require a larger dome. Mid-range zoom - Sony 20-70mm goes fairly wide on the 20mm end, but still gives you good zoom capability for fish portrait shots from a distance. Wet optics - Sony 28-60mm in a flat port paired with a Nauticam WWL-1 or Weefine WFL09S.

I've carried my rig (housing on a tray with port, camera and lens inside, no arms or strobes) on a shoulder strap as my 'small item' in addition to carry-on. This removed a significant amount of weight from the aforementioned carry-on, and didn't cause any issues.

Weird, they seem to be gone from the main Retra store. DiverVision lists them in stock - https://www.divervision.com/products/retra-neoprene-for-bumpers You will also need the bumpers - https://www.divervision.com/products/retra-bumpers It's possible (and cheaper) to make your own jackets out of some old discarded wetsuit, but without bumpers, they will slide around. I have the original, pre-bumper jackets, and they're a bit annoying that way, although tightening them down with zipties has resolved that issue.

I ordered a pair of white diffusers with my Retra Pros, but ended up using them only as protective covers in transport - I find that bare strobes already have a wide enough beam, even when used with a fisheye, and I prefer to have the extra reserve power for larger scenes. It is, however, a matter of personal preference - I know other Retra users who do shoot with the diffusers on. What I do find very useful are the reflectors - I put them on every macro or blackwater dive. They turn a diffuse beam into a very sharply defined one, allowing fish portrait shots from up to several meters away without much in the way of backscatter. I also have an LSD, but I don't use it as often as I probably should, as taking off the reflector, putting on the LSD, repositioning the strobe above the camera, aiming the snoot, taking the shot, then doing the whole thing in reverse is usually too much of a hassle. Perhaps I should sell it and get a miniflash with snoot to run alongside the Retras.

Thailand has good healthcare in general, but the diving is not as good as Philippines or Indonesia. A combination of decent diving spots and easy access to major hospitals is even harder to come by - the closest thing I can think of would be Phuket; you can dive Kata Beach or day boats there, which is not magnificent but still decent. Khao Lak is also an option - you can do day boats to Richelieu Rock or a short liveaboard. Another option, kind out of of the left field - have you considered blackwater diving in Florida? I haven't been there personally, but I understand that it is one of the world's hotspots for blackwater, and it would obviate all the issues with international travel, healthcare, etc. It's very difficult from your typical muck diving, but it's still macro.

28-60mm is a Sony-specific E-mount lens, originally released as the kit zoom for the A7C compact full-frame mirrorless. As far as I know it does not have a DSLR equivalent. Since it has a shorter flange focal distance, there is no way to adapt it to a DSLR, as the space where its mount sits is occupied by the mirror box.

For what it's worth, here's a series of comparison images taken in a pool. I was using a Sony A6300, so an APS-C sensor, but it should be broadly similar on FF if you adjust for the crop factor. 10mm (15mm-equivalent) behind flat port: nullnull Same behind dome: 16mm (24mm-equivalent) behind flat port: null Same behind dome: null 18mm (27mm-equivalent) behind flat port: Same behind dome: null 30mm (45mm-equivalent) behind flat port: Same behind dome: null You can see the loss of AoV, pincushion distortion, and loss of sharpness caused by a flat port at this medium-to-wide focal lengths. The 10mm and 18mm examples were shot with Sony 10-18mm f/4 lens, 16mm and 30mm were shot with Sony 16-50mm PZ kit lens; housing and ports were from SeaFrogs. Regarding 8-15mm fisheye, it is obviously a very capable setup, but it is also quite expensive. You will need a $650 N100 to N120 adapter, a $650 extension ring, a $1476 dome, a $399 adapter, and a $1249 lens, plus maybe a zoom gear (you can print your own far cheaper than a brand-name one). If you will want to use it as a zoom lens, rather than switching between full circle at 8mm and diagonal coverage at 15mm, you will also need a teleconverter and another extension ring, so figure on spending an additional $1k or so. By comparison, flat port 45 is $518, and 28-60mm lens is $500. To get it shooting wide, a WWL-1B is $1546, and the required M67 to bayonet mount adapter is another $107, so we're talking about a ~$4500-5500 setup vs. a ~$2700 setup.

Without a dome you can't really shoot wide due to increasing levels of pincushion distortion. If you want to stay with a flat port and keep things reasonably inexpensive, consider #37165 N100 Flat Port 45 and Sony 28-60mm f/4-5.6 lens. This will give you a reasonable zoom range to work with for stuff like fish portraits, and later on you can augment it with a WWL-1B for true wide-angle. You can also use it with wet diopters for macro.

If it's that important, you could use solid foam to make float jackets for the strobes? It probably wouldn't work for models with side-mounted controls, such as Ikelite DS160/200/213, or the optical receivers on Marelux Apollo III, but for either Retra or Kraken strobes it shouldn't be an issue. Me, I just mount my floats on the outer arm segments, close to the strobes, and it doesn't seem to be an issue. I haven't seen those size limits on small items enforced nearly as rigorously as carryon weight limits. As long as it fits under the seat in front of you, it should be fine.

My last trip, I just hand-carried my housing, on a tray, with the camera inside, as my 'small item' and it didn't present any issues. The Etihad check-in agent in Bangkok did pooh-pooh my overweight carryon, which contained, among other things, the strobes and the batteries, so next time I'm flying, I'm going to mount the strobes, superchargers attached and batteries inserted, right on the tray handles.

Seems like AOI is branching out from Olympus/OM Systems into Sony now? As I understand it they used to partner with Fantasea, but I haven't seen any new releases from that company in a while now, so maybe it's no more? https://www.aoi-uw.com/products/housings/aoi-uh-a7iv.html Looks very interesting and relatively very affordable - Backscatter already has it listed for $1599, and that includes a vacuum system, and a TTL- and HSS-capable flash trigger, which would typically be quite pricey add-ons. A SeaFrogs A7 IV NG housing lists for $677, but add a ~$300 s-TURTLE, a ~$300 Leak Sentinel, and a ~$100 tray, and gets into the same ballpark. The built-in depth gauge is also a nice feature - not quite the same as mounting a full dive computer on the camera, but still quite handy, especially for blackwater dives. Controls layout looks well thought out. There doesn't seem to be an option for an add-on viewfinder, but there are inexpensive LCD magnifier hoods, including a 90-degree one for macro/muck diving. Cordless flash trigger connection (there is a unit that installs on camera hot shoe with contact pads that mate with contacts in the housing) should save on wear and tear on the famously complicated Sony multi-interface shoe connector, as you don't need to disconnect it every time you remove the camera from the housing. As far as downsides go, the photos and drawings don't show any bulkhead connections, so no option to run it with an external monitor other than maybe a housed phone over WiFi. Also, the only domes offered are 160mm and 220mm acrylics - no option for a fisheye minidome for CFWA; I wonder if Zen will make a DP-100 in AOI's new AX mount. I also don't see any zoom gears yet, but I'm sure those are coming.

Are you sure it was water intrusion from the outside? I've had batteries leak electrolyte inside my strobe - granted, those were NiMH AAs, but Li-Ion cells can do it as well.

I was browsing Divervision looking for something unrelated, when I came across this: https://www.divervision.com/collections/strobes/products/ikelite-ds-200-ttl-strobe-40622 Looks like they're clearing some old stock - Ikelite DS200 is discontinued, heavy, bulky, and only takes electrical sync (although optical adapters are available), but unless the battery packs have degraded beyond usable capacity, $249 for a 200 W/s strobe is still a tremendously good deal.

It doesn't. On my A6700/UWT combination, going above 1/160s automatically engages HSS (the appropriate symbol is shown on screen), which requires the strobes to also be in HSS mode, or they will fire out of sync and not expose the image at all. With a simple SeaFrogs trigger, HSS mode is not engaged, and it syncs at up to 1/250s - the narrow black band on top of the image appears at 1/320s. No tricks are needed to exceed the shutter speed.