Wide/fisheye lens and housing for the RX100 mk IV?

I am on the hunt for a 4k video solution and stranded at the RX100 mk IV. Decent IQ, modest pricing, cheap housings.

First of: I am eying the Fantasea frx100 housing(s), does it have any significant drawback compared to Ikelite?

Speaking of Fantasea, does the mk IV camera fit in the mk III housing? Fantasea offers a retrofitting service, can it be done at home?

As for optics, I want the best. Does the WWL-1 have any serious (and somewhat lighter...) competitors in the wet wide lens department?

I imagine the Fantasea is better than the Ikelite -- never liked any of the controls on Ikelite housings, so it's hard to imagine how it could be worse.

The MK IV and MK III have the same body I believe, so the IV should fit in the MK III housing.

Aside from the WWL-1, perhaps have a look at Inon's UWL-H100 wide angle converter + dome and the Fix/Fisheye UWL-04.

I am using the Inon UWL H100 plus dome with my RX100iv and I'm quite happy with it. I think its about 300g lighter than the UWL :-)

Thanks for the feedback! How do the corners look at f5.6 with the h100? I have the feeling, that the wwl-1 would allow one more stop compared to the Inon.

It is not a matter of stops the WWL-1 is six elements the UWL-H100 is five so less glass which means less contrast. Before the WWL-1 arrived the Inon was the best. In any case non are good for video as they are not rectilinear plus the RX100 can't white balance so you need a lens that can take a push on filter. Up to now the Inon UWL-H100 in the base version has been the choice but it does have a lot of fringing outside the centre of the frame

It is not a matter of stops the WWL-1 is six elements the UWL-H100 is five so less glass which means less contrast. Before the WWL-1 arrived the Inon was the best. In any case non are good for video as they are not rectilinear plus the RX100 can't white balance so you need a lens that can take a push on filter. Up to now the Inon UWL-H100 in the base version has been the choice but it does have a lot of fringing outside the centre of the frame

Fringing/CA is no good for 4k... Right now I have an ancient Subawider III at hand, I think I don't buy anything else before I can test it.

When things are in motion you don't see for still images more of a problem

When things are in motion you don't see for still images more of a problem

True.

I am looking for an alternative option as well should make a final decision in the next week

In a few weeks time (certainly not next week:() I can test the Subawider III underwater. It is meant for the nikonos 35mm lens, which is amphibious (=can be used in land too). This gives me hopes, that the corrector can be used with land use optics. Its sibling, the Subawider II provides great results with the nikon AW. Unfortunately no production anymore, but there are pieces available at ebay.

If it is designed for 35 May vignette depending on the size of the rear lens

If it is designed for 35 May vignette depending on the size of the rear lens

Yepp, I think I'll have to zoom in a bit. The rear lens is quite big, >40mm, but looking though the glass it looks to be shrunken to ~20mm. I am more afraid of what the lens shades will do.

In that case it is not worth it. I am going to do a write up about lenses for video soon. Won't be difficult as really there are only 3 options

In that case it is not worth it. I am going to do a write up about lenses for video soon. Won't be difficult as really there are only 3 options

Still, it might be viable, It converts the 35mm lens to 17mm, meaning if I zoom to 35, I still get 100°FOV, just as the plain h100, more than a GoPro with flat port.

No because the distance from the lens increases so you loose filed of view. The maximum effect is when the lens hits the port. Furthermore increased distance also means loss of contrast and increased chromatic aberrations

No because the distance from the lens increases so you loose filed of view. The maximum effect is when the lens hits the port. Furthermore increased distance also means loss of contrast and increased chromatic aberrations

True, on the nikonos (and the AW1) it was sitting directly on the lens, no ports in between. I'll check how it behaves on land with spacing.

So if summarise correctly, you can use fisheye lens for UW photography, but not video because you cant attach a filter to the fisheye lens? Sorry for this stupid question, i'm really new to this

So if summarise correctly, you can use fisheye lens for UW photography, but not video because you cant attach a filter to the fisheye lens? Sorry for this stupid question, i'm really new to this

You can put a gel filter behind the conversion lens or inside the port glass. I do the latter with my gopro+ufl-g140 setup.

Two issue first the filter takes one stop of light if you go at depth you run into problems. Second you need to custom white balance when you shoot with lights. The second on the rx100 is a no go hence no filters in the housing and no fisheye lenses for video on the RX100

Interceptor, could you elaborate for me as a newbie a bit more?

I own a rx100 iv and now i would like to achieve these awesome under/over water split shots - both in photos as well as in videos. So, i found out that i need a fisheye lens including a large dome. On this site i read that the FIX UWL-04 or the INON UWL100 (with dome) will give me the ability to get those shots. Now i am bit confused, because you said that for video, the combination with the rx100 iv is impossible?