Chris Ross

I would suggest you try polishing with cerium oxide others have reported it works, you would just need to sure the materials used when polishing have no grit in them- you need to get optical grade material, this link talks about it: Polishing vs Regular Grade Cerium Oxide: How To Choose?Discover the essential guide to choosing the right grade of cerium oxide for your polishing needs. Learn the differences between Polishing and Regular Grade cerium oxide, including insights on purity,

My concern would be the rushed decision. You are coming from Ikelite so nothing will carry over. Do you want to go with Nauticam? Isotta will be somewhat cheaper but you would have to wait for the A7RVI to appear, in particular their ports and extension rings are quite a bit cheaper. To use a WACP-C based on prices from UW camera store the housing zoom ring and adapter come to 3873 euro with Isotta and 4550 euro in Nauticam. You would need to add the WACP port, lens, camera etc to that total The Isotta housing will be more compact and uses B120 ports while the Nauticam is N100 and requires the pricey N100-N120 adapter for many lens combinations. Isotta have published a port chart for using Nauticam wet lenses on their housings here: https://www.backscatter.com/images/article/content/Port-Charts/Isotta-port-chart-Nauticam-Lenses.pdf Your other option in this regard might be a WWL with the 28-60, somewhat cheaper to purchase and reported to have very similar optical quality. You could do this in Isotta as well.

No port system, it's a fixed port and it allows you use the 16-50 kit lens or apparently the 50mm macro fits, but it has pretty short working distance. If it were me, I wouldný want to use the CMC to get just 0.9x with little to no working distance. You can take decent pics, but it's a kludge solution compared to a real macro lens.

I haven't used them but I find the idea of the Nauticam systems using only a kit lens with either a diopter or WWL somewhat limiting. In general the the WWL is sharp and provides good to great images by all reports, however the width of the frame is about that of a 14mm rectilinear lens, the barrel distortion gives a 130° diagonal, which seems like a 10mm lens, but with barrel distortion the corners are stretched the consequence being is the horizon frame field is about that of 13-14mm rectilinear. Macro is another story, you can add diopters and get near macro magnification but working distance is very limited. the 16-50 with CMC-1 gives you 0.9x at 45mm working distance. Compare that to the 105mm Z lens which gives 1:1 with about 120-130mm working distance. The 16-50/CMC-1 only focuses between 45 and 75mm from the front of the diopter so only gives quite a limited magnification range. I'd estimate 0.9x - 0.4x approximately. It seems there is an adapter available for Sealux to Isotta (looks like a custom order so a bit of a wait), I'd be strongly tempted to go that way if macro is important to you. https://www.uwcamerastore.com/isotta-adaptor-ring-for-sealux-1p

The compact port extension is #18520, to check this just search for Nauticam 18520. The compact port system is an old system and as far as I can tell has to be used with the compact port base. You are talking about using N100 and N120 systems. Looking more closely Nauticam don't make a N100 20mm extension, so your only option is an N120 20mm extension. I understand about not wanting to spend big up front, but the 20mm extension may become an expensive paperweight, depending upon which lens you eventually switch to. At Backscatter the N120 20mm extension is $660 longer extensions are $700 plus. I'd suggest understanding better which lens you hope to use and match it to your photography goals - buy right - buy once. The obvious solution it seems might be a 16-35 lens, but other solutions are significantly more popular UW wide angle photography - fisheyes and wet optics specifically. The right choice for you will really depend upon what you want to shoot. To get you started on 14mm lenses see this thread: There are other threads on various Sony wide angle lens options if you use the search function.

The only reason I think that might give you trouble is if the lens is too wide through the N100 part of the extension. Obviously the bottom part will but this is a fairly fat lens that only gets narrower right at the bottom, but I expect it's probably OK. You can test to see if the lens fits through the N100-N120 you already have. The question you haven't asked is if you really want to use this lens UW? Wide rectilinears have their uses of course, but the 180mm dome geometry requires the lens to be positioned with the entrance pupil forward of the optimum point at the dome centre of curvature to avoid vignetting, meaning the lens won't perform as well as it would properly positioned. You will see that the port chart shows the 250mm dome with an " * " meaning that is the optimum dome to use. The 180mm dome will certainly work and the images produced will be usable but other lenses may well do better particularly in the corners, There are other Sony lenses which may work better with the 180mm dome. I would suggest asking for experience using the Sony 180mm dome with the 14mm f1.8G lens, to see if you would want to do that. Apparently some of the new 16-35 lenses work quite well with the 180mm and I think there have been some tests published on this site from memory. The other question is what sort of photos are you thinking you might like to take and is a 14mm rectilinear the best option for this?

Be interesting to test it out, the test case would probably be shooting into the light, like a sunball or something.

Nice, I'm yet to dive from up there, it's on the list though

There is good reason they are locked, so that people don't change their post in the event of a dispute. I do agree a mark as sold button would be worthwhile, but not sure if forum software allows this. We can check.

You can download the manual which will include how to setup the strobes - just go to the S&S website. They have a few procedures to customise the strobe to work with various cameras.

It's been a long time coming interesting to see if it was worth the wait, so far I can only find pre-order with some basic pics on the two sites mentioned.

expect you're right, I couldn't see the connector which is why I mentioned it.

You should also probably remove the trigger as well - is it an UWT trigger or some other type? What are the cables attached to?

They could be different types of glass, there are many different types of optical glass around. BK7 is one of the most common. The procedure is straight forward - on a dive boat either keep the lens wet or apply the wet neoprene lens cover and keep it cool. Soak the lens for a period in fresh water. Then remove it and dry it straight away. I have a battery duster that I use, you could also use a blower attachment on a scuba tank or a compressed ir hose, depending on what you have available. Then dry with a microfibre cloth.

Perhaps, but in general higher concentrations of salts are more corrosive, in any case you can't dissolve these markings, maybe they have etched the glass, maybe the compounds have chemically combined with components in the glass. Apparently BK7 glass (a common optical glass) only has moderate chemical resistance. This topic has been raised many times and reports are dissolving the spots doesn't work and they require polish to remove. Whatever the mechanism, the cause is still allowing water to evaporate on the glass and the prevention is blowing off or wiping dry so evaporation doesn't occur. Apparently cerium oxide is slightly softer than BK7 glass and can polish without causing micro scratches.