Inon 170mm dome for Olympus lenses

As noted in a thread on CFWA, the Inon dome is a good option for those wishing to shoot the Oly Pro lenses;I'd like to share my experience in case anyone is curious. The dome was originally meant for the 4/3 evolt system and the old 7-14 and 8mm fisheye- the PPO-E04 dome that Olympus shows on their latest E-M1 port chart was also meant for these lenses. I bought my dome from Divervision for about 575, which makes it pretty cheap compared to other 170mm domes, even after the you get the OMD port adapter and 2" extension (this is for the Oly housing, and I believe- but I'm not sure- that you can also adapt 4/3 ports to the Nauticam system).

With the 2" extension, this dome works well with the 12-40 Pro lens- I now have several dives with that combination, and I'm happy with it. Center sharpness is great, and I can crop pretty tightly on small critters at 40mm and end up with nice results. Corner sharpness is better than with the flat port- meh wide open, acceptable stopped down a bit.

I have just one dive with the dome and the 7-14 Pro- conditions were great for cold water divers, but not conducive to really show off the equipment. I didn't end up with any keepers, as it was a fairly short, deep dark dive. The lens focused quickly through the dome, and center sharpness at both 7 and 14 mm was excellent. Corners were mushy wide open, but at f7.1 are pretty darn good- check out my buddy's deflator hose in the picture (OOC jpeg, nothing done in post). While testing it out, I was able to lock focus on objects less than 3" from the front of the dome, but as Interceptor noted in the CFWA thread, rectilinear lenses aren't the best for shooting that close. I'm perfectly willing to stop this lens down for most stuff underwater, however; the wider aperture, weather sealing, etc. are features that I'll take advantage of topside. As expected, this lens requires the same 2" extension that the 12-40 takes.

I also have the 8mm f1.8- unfortunately, it's a shorter lens than the other Pros so you have to remove the 2" extension to make it work. Doing that's kind of a pain, but nothing is easy in underwater photography, right? In testing, it seemed to lock focus on objects as little as an inch away from the front of the dome. I have not dove with this lens yet, but will try it out next month in Bonaire.

I also tried the 60mm macro lens behind this dome with the 2" extension- it works fine, so you can always make this a one port solution if you're that limited on space. For my purposes, I'll use 2 ports- the Inon dome and the Oly flat port with a swing away macro adapter.

Awesome, thanks for the quick review. I really want to work my way to all three of these Pro lenses eventually and knowing there is a one port call for all of these is a massive wallet saver...and space saver.

This may sound silly but is there an adapter to PEN housings? I would love to assume so.

Also is there an acrylic alternative?

Been eyeing another port for a while as it seems to also house both 12-40 and 7-14 lenses - Athena WZ7-14II. Most of the literature about it is in Japanese so its not easy to find out much about tbh. Found it on divervision.com, it looks like its also a 170mm dome. Anybody seen this before or used it?

Working closely with Americans and for Americans for a few year now, still love the term 'dove' where us Brits would say 'dived'. Please, I mean no harm just an observation haha

Interesting- I guess conversationally we use dove and dived interchangeably, and at least in my case I default to dove when typing. I like those kind of differences As far as PEN housings, I believe that the 12-40 is too wide. The 7-14 is even bigger, so I'm guessing it's a no go as well. I'm not aware of an acrylic dome for the those two lenses, either.