New Nauticam Wet Wideangle WWL-C

Well..I just. bought a WWL-C.  I have a trip in October and really wanted to have the lens for it.   

I tested it in my wash basin with the nauticam LX-10 case and vignetting was eliminated at 28mm for f/11, f/8. f/5.6, f/4, f/2.8, which is way better than I was expecting considering Nauticam's compatibility chart:

https://drive.google.com/file/d/1SLJDkS0NLLbYHUShF6Krof-dufWMynop/view

says 32mm-72mm.  Am I missing something here?  I made sure to burp the lens. Could it be the photo aspect ratio or because I was using aperture priority mode during the test?  Right now, I don't see why they stated 32mm.    

I am super happy though with only having to zoom to 28mm, which gives a 122 deg FOV (using ChrisRoss's ratio method above). 

Vignetting is mechanical,  depends on the size of your adapter and how far it is from the lens - I would guess Nauticam takes a worst case scenario so they don't have people yelling at them that their rig vignettes at 28mm.    Basically you need to zoom in till you can no longer see the edge of the lens in the corners.  It may change with focus though as those types of zoom lenses often change focal length as they focus closer.

12 hours ago, mdo905 said:

Well..I just. bought a WWL-C.  I have a trip in October and really wanted to have the lens for it.   

I tested it in my wash basin with the nauticam LX-10 case and vignetting was eliminated at 28mm for f/11, f/8. f/5.6, f/4, f/2.8, which is way better than I was expecting considering Nauticam's compatibility chart:

https://drive.google.com/file/d/1SLJDkS0NLLbYHUShF6Krof-dufWMynop/view

says 32mm-72mm.  Am I missing something here?  I made sure to burp the lens. Could it be the photo aspect ratio or because I was using aperture priority mode during the test?  Right now, I don't see why they stated 32mm.    

I am super happy though with only having to zoom to 28mm, which gives a 122 deg FOV (using ChrisRoss's ratio method above). 

I've done 4 or 5 dives with mine on a LX-10 and I find I need to zoom in to about 30mm. I could see a slight vignette in my pool tests at 28mm (see the lower left corner in the 28mm photo below vs. 30mm).

As Chris says, it is a "mechanical" issue so it could be that you are attaching the WWL-C closer to the port than I am -- but I'm not sure how that would be possible since the only way I know to attach is via the M67 bayonet adapter which just screws directly onto the fixed port of the NA-LX10 housing.

First picture is 28mm and second is 30mm.

The difference between 28 and 30mm is minimal - I could see how someone would say 28mm is fine.  Because the edge of the mounting ring is not in focus it's a transition, rather than a hard edge vignette.

The issue with the LX10 is that the fixed lens telescopes a lot when zooming. The port on any housing has to be quite long if it is to accommodate the full zoom range.

When the LX10 lens is at 24mm equivalent the front element is retracted a long way from the front of the port. This results in vignetting and very soft corners in stills from 24 - ~36mm when shooting stills using wide wet lenses for 28mm equivalent lenses. The 36mm equivalent crop applied when shooting 4k video eliminates this vignetting. 

I have tested and confirmed this using the LX10 in Nauticam housing using both the WWL-1 and AOI-UWL-09. I have not had the opportunity to test WWL-C but the Port Chart does not fill me with confidence.

Issotta are the only manufacturer that I am aware of that produces a LX10/LX15 housing and a user replaceable 67mm threaded short port:

https://www.isotecnic.it/en/products/compact-housings/panasonic-eng/panasonic-lumix-dmc-lx10-dmc-lx15-eng

https://www.isotecnic.it/en/products/compact-housings/panasonic-eng/panasonic-lumix-dmc-lx10-dmc-lx15-eng/m67-short-port-for-g7x-mark-iii-lumix-lx10-lumix-lx15-detail

This short port combined with WWL-C could produce good results at 24mm equivalent on LX10, although you'd lose the benefit of zoom-through with the compatible wide wet lenses. I'd love to see if someone has tested it. You need to swap to the standard port to enable the lens to zoom if you wanted to use close up wet lens.

This mandated port swapping on a compact system was the reason I sold the LX10 and switched to m43 and GH5. My wide and close up wet lenses and bayonet mounting hardware moved with me onto the Panasonic 14-42ii and deliver spectacular results with stills and video compared to the LX10. The versatility of the N85 port gives you lots of options for macro, wide and fisheye lenses.

4 hours ago, joncroweucl said:

This short port combined with WWL-C could produce good results at 24mm equivalent on LX10, although you'd lose the benefit of zoom-through with the compatible wide wet lenses. I'd love to see if someone has tested it. You need to swap to the standard port to enable the lens to zoom if you wanted to use close up wet lens.

I posted some pictures earlier in the discussion (30 Aug 2020) at 28mm and 30mm. Below is a picture at 24mm and you can definitely see the vignetting.