MWL-1 or Kraken/Weefine KRL-09s on MFT

I'm curious about the performance of macro to wide lenses on MFT. Most of my diving is typical holiday diving where you never really know what you're going to see and there is rarely an opportunity to repeat dives. On dives where I have absolutely no idea what I will encounter I currently use the Olympus 12-50mm lens in the special Nauticam port with a a Saga +10 on a flip adapter. This gives me reasonable macro but the wide end is pretty disappointing, both in terms of IQ and in terms of being wide enough.

I've contemplated getting the MWL-1 or KRL-09s to solve that problem, by having a dedicated macro lens that will also give me a 150° close to fisheye view. I also enjoy wide angle macro so this might be the perfect fit. However, most reviews I have found and most sample images were shot on full frame. Both Nauticam and Kraken emphasize that the lens needs stopping down to F16 on FF, but it is not clear how this translates to crop sensors. On land, the DoF on FF f16 would match f8 on MFT. Generally I'd be fine stopping down to f11, after that I would run into trouble with my small S&S YS-02 strobes. F8 would be preferable.

I will keep my Fisheye and rectilinear WA, so please let's not make this into a specialised lens vs Jack of All trades discussion. I know I will get superior IQ with my Panasonic Fisheye (although I'm not so sure about the wideangle) and I will also lose the ability to do split shots and I will keep bringing those lenses when I know what awaits me. The question is, how much worse is it really for general wide angle shots? 

So I'm looking for people who have shot one or even both of the mentioned lenses on MFT. How is corner sharpness when stopped down to f11 and f8? How sharp is it in the center and corners compared to the Panasonic Fisheye (I use the 4.33" acryllic dome). Sample images would be much appreciated, especially high resolution images.

If anyone has used both (in this case even just on FF) I would also be interested if the Nauticam lens is really that much better at 1k€/$ price difference. The glas dome compared to acryllic is a pro, but it also needs an additional float collar, so if they are on par in terms of IQ I can't see myself investing in the Nauticam lens.

This is a question that has been asked before and I have never seen a positive answer, there's only a handful of reviews of the MWL on full frame and they seem to state that f16 really is necessary on full frame.  The review by Jack Connick is here:

Review: Nauticam MWL-1 Conversion Lens by Jack Connick :: Wetpixel.com

If you could download the sample shots to view at full res you could see where the image quality degrades.

I would think that if the issue is corner sharpness due to depth of field needed to bring a virtual image into focus the the rules about f16 on FF being equivalent to f8 on m43 would mean you could shoot f8 and get equivalently good results on your m43 setup.  But if f16 is needed for overall sharpness that is another issue.

You might want to see if you can manage to download the full res images from the download links in the review - I tried and it asked for a password and I gave up.  It might give you some insight - or you could PM Jack and ask if he has experience on smaller formats with the MWL.

Would you say that if the center stays sharp in the FF reviews even at wider apertures, that we can conclude that it is a DoF issue that requires f16 on FF? This review of the KRL-09s by bluewaterphoto shows that for that lens at least the lens seems to stay pretty sharp in the plane of focus in the center. I've not seen a comparison review of both lenses done by anyone.

It might - or to be more precise that would be one possible explanation.  Lack of reviews period, let alone comparisons is an ongoing problem for wet lenses apart from the the more popular variety like the WWL.  

You could consider the UWL -100 or the newer UWL-95 with a dome which give similar fields of view.  Sample images of decent size for the UWL -100 + dome are available here:  The Ultimate Wet Lens Sample Post | Mozaik UW (housingcamera.com)

The pics are good size at 1920 x 1080 and have EXIF data intact so you can check where they are zoomed to and the aperture, you want to look at the sample taken with the Sony APS-C - your m43 will have better corners than the sample shown.  The dome gets you 140 deg field of view.

Don't know much about the Kraken lens but is a big lump of a thing to carry around UW until you decide to attach it - it's 125mm x 135mm.

What makes it very attractive to me is it’s attachment to a macro lens and that both of them are expressly advertised as working on a flip adapter. I’ll probably give the Kraken a shot if my wallet allows before my next trip. I’ll report if it ever comes to it. 

I have had the Kraken flight a few months. I used it for 2 days / 5 dives this week up in Gods Pocket. I can post some images comparing it to my Sigma 15mm FE this weekend. All shot on the D850.

That would be great. Thank you!

As promised here are a set of photos taken with the Kraken KRL-09 / 60mm / Nikon D850 setup. For contrast a couple of photos with the Sigma15mm in a 170mm dome.

All of these photos were taken last week up in Gods Pocket Resort, British Columbia.

Kraken Photos:

Sigma Photos:

Thank you! Looks pretty good to me. The first shot is really really cool. Corner sharpness looks acceptable to me on the second shot and I do like the out of focus divers. Definitely a different look. What apertures did you use for these images?

2 hours ago, hyp said:

Thank you! Looks pretty good to me. The first shot is really really cool. Corner sharpness looks acceptable to me on the second shot and I do like the out of focus divers. Definitely a different look. What apertures did you use for these images?

The first two images are on Instagram with all the details. I will be posting more from this trip in the next several days.

Most shots were f11-f13.

https://www.instagram.com/david_hicks_wild_images/

However I find it a heavy lens to put on a flip diopter and for ease underwater, a float ring helps. 

Using OM1 in nauticam with 30mm and KRL 09s.

Sorry, typo- too heavy for a flip adapter IMO

38 minutes ago, Stxpc said:

Sorry, typo- too heavy for a flip adapter IMO

I actually shoot the KRL-09 on a dual flip adapter with a Subsee +5 diopter on the other ring. It's good for building up your bicep muscles! I don't have any trouble using this way. I had not thought about using a float ring but might look into making one. Sounds like another 3d fun printing project!

6 hours ago, Stxpc said:

However I find it a heavy lens to put on a flip diopter and for ease underwater, a float ring helps. 

Using OM1 in nauticam with 30mm and KRL 09s.

Doesn't the KRL-09s have a built in float collar, 200g negative seems fine to me underwater. Topside I would keep the lens down.

Do you have any samples with the 30mm on the OM1? Which apertures do you use?

My KRL 09s weighs 2.2 lbs.  no integrated. float collar. 

Below: 30mm at f8, 1/30, iso 100

Interesting: https://www.backscatter.com/Kraken-KRL-09S-Underwater-Wide-Angle-Conversion-Lens is just one place that says in-water weight is at ca 200g because of the integrated float collar. Obviously, above water it will still be heavy (backscatter says 2.5lbs or 1145g).

I just went and weighed my KRL-09s with a luggage scale in and out of a sink of fresh water. The removable lens hood is attached.

1120g dry weight

230g submerged

A recent picture I took with this port in Australia: