I tried a year ago both the 3.5" and the 4.33" nauticam ports with extensions on the em5 camera and olympus 9-18mm lens.
The results are no good. The 9-18mm is a great lens for land use but not for UW. Close focus is not good and even with diopters (achromatic too) attached the results are pretty bad. The 4" long semi dome port is good and results are reasonable with at least a +2 diopter in the case. Better an achromatic one. In the end I use this 9-18mm lens UW very little!.
I much prefer the 8mm FE lens with the small 3.5" dome and use that also when I want really wide and CFWA. Packing the dome and the 8mm lens is of little weight and space!
I have been using with good results the 4" semi dome port with the 12-50mm lens with a cmc flip diopter. I get true 24mm equivalent all the way to true macro. This is a reasonable versatile setup and have been using daily on my last Cozumel trip. The semidome also houses and works excellent with the 60mm macro lens.
Lately some options on wet wide angle add-ons have appeared but have not tried them The INON and the Nauticam seem to have a good wide wet solution matched to the 14-42 lenses (the Panasonic one seems the better one). And Nauticam offers a bayonet mount for easy detachment. This is an expensive setup but you could have a full solution from 110° wide to macro ... underwater . I would like to hear on someone that has tried it. The INON solution is less expensive and less wide but a bit less quality. The Nauticam advocates great quality but weight is 1kg and 1k € the cost!!!
- Storker likes this