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troporobo

Recommend a lens/port for CFWA on m4/3?

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I've really been enjoying the Olympus 60mm macro and Subsee diopters for super close up shots. Now I want to branch out to close focus wide angle / wide angle macro with some of the same subjects I regularly encounter.

 

My criteria in priority order are (1) closest focus distance, (2) widest FOV, (3) rectilinear, and (4) also excellent for landscapes above water. An added bonus would be a reasonably sized dome, say 150-170mm. For those reason I am drawn to the Olympus 7-14 f2.8 Pro. The Panasonic 7-4mm f4.0 would be next on the list. The Nauticam WWL-1 would be a distant third due to reason #4 but if it saved having to buy a port I could have it *and* a land-only lens. I am not interested in a fisheye lens, I simply don't like the effect regardless of subject.

 

There are a few things I don't quite understand though. I have not searched exhaustively but haven't found closest focus distances for these lenses behind a dome. I also don't appreciate why the usual recommendation for CFWA is for a fisheye lens, unless it is closer focusing distances and/or smaller ports.

 

BTW, I am using an OM-D E-M5 in a Nauticam housing. I'm planning to upgrade to the E-M1 in about a year, hoping that the Mk II that is rumored will have an improved focus capabilities, and if it doesn't, hoping to snaffle the original E-M1 with a price drop after the announcement.

 

I'd love to hear some recommendations!

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I just shot the Olympus 7-14 behind an Inon 170mm dome on a dive a couple of days ago. The viz wasn't the best for that kind of shooting, but I could get the dome as close to the subject as I wanted and still get focus. No real keepers from that distance, but that's on me- not the lens. It was quick to focus, and corner sharpness was...acceptable- better than the 9-18 and mini dome I used to shoot, but not as good as I hoped. I downloaded the pics to my computer but haven't done anything with them in Lightroom yet- maybe my opinion will change.

 

For the rest of the dives on the trip, I shot the 12-40 either behind the same dome or with a flat port and diopter. The 12-40 is much more flexible, and as I've been shooting it longer, I have a higher comfort level than with the 7-14. I plan on using the wider lens more next month in Bonaire, along with the 8mm Pro fisheye.

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I just shot the Olympus 7-14 behind an Inon 170mm dome on a dive a couple of days ago. The viz wasn't the best for that kind of shooting, but I could get the dome as close to the subject as I wanted and still get focus. No real keepers from that distance, but that's on me- not the lens. It was quick to focus, and corner sharpness was...acceptable- better than the 9-18 and mini dome I used to shoot, but not as good as I hoped. I downloaded the pics to my computer but haven't done anything with them in Lightroom yet- maybe my opinion will change.

 

For the rest of the dives on the trip, I shot the 12-40 either behind the same dome or with a flat port and diopter. The 12-40 is much more flexible, and as I've been shooting it longer, I have a higher comfort level than with the 7-14. I plan on using the wider lens more next month in Bonaire, along with the 8mm Pro fisheye.

 

Im very interested in this dome if it works well with both 12-40 and 7-14. These are hopefully my next two glass purchases. My previous research has indicated that they would not work with this dome, although I have no idea why. If anyone has any idea why they 'should not' work I would love to know.

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I can confirm that the Inon dome works great with the 12-40, although I note corner unsharpness at 12mm wide open, particularly in the lower left corner. That kind of makes me wonder if it's my copy of the lens that's the problem. The only reason I can think of why you would have heard that the Inon dome wouldn't work with these lenses is the fact that you need a 2" extension (and Oly EP08 adapter). Once all that's in place, it's pretty similar to the Oly 170mm dome.

 

Rather than clog up the OP's thread, I'll try to start a new one with more info about the dome as I think it's a great port option. I will add a pic here for an example of CFWA for proof of concept (not artistic merit). It was shot last weekend in very challenging conditions in Washington's San Juan Islands- less than 6' of viz and strong currents. It's mildly edited, and was shot at f2.8 1/60; the bumps are pedal sea cucumbers.

post-50197-0-87311900-1459008299_thumb.jpg

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The reason why the recommendation for CFWA is a fisheye is that you need to get as close as possible and still maintain reasonable sharpness

With rectilinear lens is very difficult to keep depth of field in the corners as you get closer and generally reef shots suffer

I have used successfully a Panasonic 7-14mm for interior wreck shots at f/8 where I do not like distortion

 

18815074993_56d8ec4b5d_b.jpgHeadlights Bikes by Interceptor121, on Flickr

 

I also would warn you about the fact that even if you have f/2.8 on the olympus you will find yourself never shooting less than f/8 on close shots. Having said that the lens is much sharper than the Panasonic but has also more distortion with resolution falling off very rapidly outside center, this happens but less noticeably with the Panasonic 7-14mm too

 

In general if you like CFWA you really need a fisheye. Distortion matters nothing when you look at a reef that is anyway irregular

 

19429534502_186f8da022_b.jpgBommie by Interceptor121, on Flickr

 

Do you see anything strange in that shot? You can then get a rectilinear lens for wreck interiors if you like me don't like human structures to be bent

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19429534502_186f8da022_b.jpgBommie by Interceptor121, on Flickr

 

Do you see anything strange in that shot? You can then get a rectilinear lens for wreck interiors if you like me don't like human structures to be bent

 

That is a stunning shot!

 

Looks sharp right to the edges and the colours are awesome. Good work

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Thanks a lot for the sample photos guys. The bommie shot is indeed very good!

 

I might have wondered just slightly about the lower left and lower right corners - more due to a quirk of perspective rather than obvious barrel distortion - but would not have been at all sure. But for my purposes, where I want a single subject (say a frogfish) filling perhaps 1/4 of the frame, I suspect the distortion would be easier to spot, at least for people who know what frogfish look like.

 

I appreciate the explanation that rectilinear lens are difficult to keep depth of field in the corners, but I am not sure why that is more true of rectilinear versus FE lenses. I assume I'd be shooting at smaller apertures than f8 anyway, perhaps much smaller, if I am trying to get both a foreground subject and interesting background in focus. I'm not very well educated on dome optics I guess.

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Once you pass f/11

 

Thanks a lot for the sample photos guys. The bommie shot is indeed very good!

 

I might have wondered just slightly about the lower left and lower right corners - more due to a quirk of perspective rather than obvious barrel distortion - but would not have been at all sure. But for my purposes, where I want a single subject (say a frogfish) filling perhaps 1/4 of the frame, I suspect the distortion would be easier to spot, at least for people who know what frogfish look like.

 

I appreciate the explanation that rectilinear lens are difficult to keep depth of field in the corners, but I am not sure why that is more true of rectilinear versus FE lenses. I assume I'd be shooting at smaller apertures than f8 anyway, perhaps much smaller, if I am trying to get both a foreground subject and interesting background in focus. I'm not very well educated on dome optics I guess.

 

Once you pass f/11 all micro four third wide angle lens drop in performance substantially. Besides the closest focus distance is double than a fisheye where you can focus on the dome

The so called wide angle macro uses fisheye lenses for frogfish and similar

Depth of field with a fisheye lens is much better and you can use a minidome that is easier to manage for close shots than a 6" minimum port that you use with a rectilinear lens

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How about the olympus 12 f2 behind the nauticam 4.33" dome for CFWA? I happen to have that lens but have not used it UW yet

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Agreed, 12mm doesn't quite do the job. I've tried (using the 12-50 lens) and been frustrated, although it was in a flat port and a dome would definitely improve things. That focal length on m4/3 just doesn't pull enough background into the shot.

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I use the 12mm and 8mm FE with Zen 4.33 dome. I agree the 12mm is not wide enough for CFWA, but it is an excellent lens for semi wide or for when you don't feel like going super wide with the 8mm. It's super sharp with excellent IQ.

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Wide angle underwater means pretty much 18mm or wider. Cfwa requires short working distance or focus on the dome. None of the rectilinear lenses focusses on the dome only the fisheye lens does it

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I have both of these lenses and haven't really found the Olympus to have more distortion or that the resolution falls off rapidly outside the center. Here is another view of the lenses:http://www.mirrorlessons.com/2015/05/28/olympus-7-14-2-8-pro-review/#Olympus_7-14mm_f28_vs_Panasonic7-14mm_f4

 

Clearly, any 7mm lens will have distortion, and corner/edge softness is significantly affected by the quality and size the dome used. Certainly if the Olympus is shot at 2.8, one could expect more edge problems than the Panasonic used at 4.0, but underwater I would expect both lenses to be used at much smaller apertures. Also, the Olympus does focus closer. To me, one of the 8mm fisheyes would be the best choice for cfwa, but the 7-14s would work, although limited by minimum focus distance and dome size.

 

Also keep in mind that if shooting jpegs, the cameras themselves will apply corrections to the images and one would get different results if using one brand of lens on an alternative brand of body (Panasonic / Olympus).

 

 


I also would warn you about the fact that even if you have f/2.8 on the olympus you will find yourself never shooting less than f/8 on close shots. Having said that the lens is much sharper than the Panasonic but has also more distortion with resolution falling off very rapidly outside center, this happens but less noticeably with the Panasonic 7-14mm too

 

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Hi Interceptor121,

what port do you use for your pana 8mm?

Simon

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For CFWA work i use the pana 8mm fisheye with the smaller nauticam 3.5' semidome, lighting is difficult but i love this combo!

 

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OK, now I am curious about the relative advantages and disadvantages of the 3.5 dome vs the 4.33 dome. Somebody please point me to some educational resources!

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This has been covered elsewhere. The 3.5" is smaller and is not a dome some users report vignetting in 4:3 picture format. It does let you get a couple of cm closer it has slightly softer corners as the port is a cut of a larger dome. Some people that do wide angle macro find important those couple of cm more. Personally I don't actually think you can really use the extra close distance if you have a tray as the strobes at 15cm from the port side to side have a shadow even when you touch the 4.33 dome. You need to mount the strobe using the M10 mount with a triclamp if you want to cover really near distance or angle the strobes inwards. The 3.5" port can be interesting if you use other lenses like the 12mm

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I must have missed that coverage elsewhere. I'll have to look for it. Tips on where to look wold be most welcome.

 

Next question, for anwone who has tried: can either of those ports produce good over/under shots I wonder?

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i did my best photo ever with the 3.5 dome port.... for CFWA the 2 cm closer focus is a huge difference....you can touch the subject with the glass and it's still in focus... interceptor do you see my mangroves photo at ocean art and UPY 2016? i did this shot with the 3.5, but before i try with the 4.33 and i can't do it.... ;-) yes, with this dome you can do almost only CFWA and the strobe positioning it's simply a nightmare.... but with this port you can obtain "different" photos.... :-) with m4/3, for only CFWA, the 3.5 is unbeatable... for me... ;-)

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