Anyone using or used a 12-40 f2.8 pro lens UW?

[Furnari]

I used to shoot the 12-40 with the flat port and a swing away diopter gadget for small stuff, but switched to a 170mm dome; while I lost some magnification on the long end, the improved quality at the wide end was pretty significant.

 

[Ardy]

Well I bought the lens and now I need to decide which port to go on my Oly PT-EP13 housing for the Em5 mk2.
It is a beautiful lens and has pushed me to make an offer on a 40-150 pro not for UW of course.

 

[Furnari]

Ardy- AOI now sells an OMD to PEN adapter, so you can use bigger ports with that housing (it takes PEN ports, as I recall). You'll also need the AOI zoom gear, which mounts differently than the Olympus gears. I could be wrong, and it might be possible to use the generic flat port, but IMO you really want a dome with this lens. The only other option is something I found while while researching and waiting for AOI to release their port adapter- Divervision sells a PEN dome from Athena that they say works with the 12-40, but I never found anything about it as far as user experience, so I was reluctant to go that route.

Sharing to highlight how great this lens is underwater...I recently got back from a trip to British Columbia. I have an M1mkIII in the AOI housing, and hoped to use the Olympus 8-25 for wider stuff but it doesn't play nice with my Inon 170mm dome. I ordered an AOI 8" dome but it didn't arrive until after I left so ended up doing all my UW stuff with the 12-40 in the Inon dome. Here's some samples to show the range; as I said above it's kinda wide, and kinda long. I don't feel I that missed any opportunities by not having wider glass or by switching to macro.

 

[Ardy]

That's pretty bloody good. I expected some distortion (due to the 4" dome) around the edges but it is sharp across the whole shot.
I'm off to bali in March and I'll definitely take it.
Do you have issues using the dome with a macro lens? Any photo's would be great!
P.S. I bought a 4" AOI dome.

 

[Furnari]

Thanks It's actually a 170mm dome originally intended for the old 4/3 system:

https://www.divervision.com/ports-gears/olympus-e-mount/inon-dome-port-olympus-with-protector-ii-set-for-zuiko-digital-ed-8mm-f3.5-fisheye-456212143338.html

​

You'll need the Olympus PAD-EP08 4/3 to OMD port adapter for that, and then the AOI OMD to PEN adapter:

AOI ER-PN_OD-37 | AOI LTD.

<table border="0" cellpadding="0" cellspacing="0" style="width: 100%;"><colgroup><col /><col /></colgroup> <tbody> <tr style="background-color: #f5f5f5;"> <td style="text-align: center;">Model</td> <td style="text-align: center;">AOI ER-PN_OD-37</td>

www.aoi-uw.com

Yes, it's very kludge but it worked just fine with my AOI housing that takes PEN ports just like your Oly housing. However, my AOI housing has a vacuum system so there's some level of risk for you; that's a lot of o-rings to watch. This set up does have minor distortion at the edges wide open at 12mm, but you can crop or stop down- you'll probably want to stop down from f2.8 anyways for wide stuff.

As far as using this dome with the macro, I tested it with the 60mm just to make sure it works. It focuses fine, but you do lose some close focus ability just due to the size of the dome. I never tried this combo with the Oly 30mm (my preferred macro lens), just because I knew it would vignette and be counter productive. When I used these lenses with my M1mkI in the Olympus housing, I would switch to the Oly macro port. Since I'm already spending your money by recommending a dome, I would suggest one of the AOI flat ports- this one for the 30mm is pretty reasonable, all things considered:

AOI FLP-04 - LENS PORTS - PRODUCTS | AOI LTD.

<table border="0" cellpadding="0" cellspacing="0" style="width: 100%;"><colgroup> <col /> <col /></colgroup> <tbody> <tr style="background-color: #f5f5f5;"> <td style="text-align: center;">Model</td> <td style="text-align: center;">AOI FLP-04</td> </

www.aoi-uw.com

...and you can get an extension ring to use it with the 60mm.

 

[Ardy]

I could just take the Oly flat port and use that for 30/60 macro but I was more interested in if I can just use one port (the AOI 4") and avoiding changing ports.

 

[Furnari]

Ah- got it. Sorry, I have no experience with 4" domes and the 12-40. My guess- and it's a total guess- is that a 4" dome wouldn't work very well, just due to the field of view.

 

[Ardy]

You could be right but it does take the 9-18mm lens. I suspect the size of the 12-40 might be the problem.
Just checked it and it will need an extension piece to fit.

 

[Caolino]

I utilize the Olympus 12-40 f2.8 Pro behind an Olympus PPO-E02 flat port. I concur the lens works well for fish portraits and in a pinch usable for smaller objects.

can you share some pictures on how it performs with a flat port?
thanks