Dome vs Wide Angle explain?

Hi all ,jsut getting back into UW photography after few years off. I have an EM5 with the 12-50mm. I'd like to go a bit wider without breaking the bank.....

My question is which would be my first stop, a dome port, or something like the inon wet lens wide angle. I believe the dome port should restore about 33% width. I can't afford both so which would be the best bet?

I'd also maybe like to pick up a wet diopter. Not sure if this would be used behind the dome port, or instead of with the flat port?

Also if dome ports restore the lens to above water, why don't all underwater cases come with dome ports, instead of flat ports?

Underwater housings (at least most of them) come with whatever port you want and the port is matched to the lens. Dome port theory is complicated (http://www.marinethemes.com/domespacer.html) is a place to start. If you are shooting macro, you can of course use a dome port but flat ports get you a bit more magnification and a bit more working distance.

Bill

yes I looked at some of the theory trying to figure it out, then I gave up and thought I'd post here! Thanks Bill

if you can get a dome for your housing and the 12-50mm then this will be a better solution, as you will get a 33% increase in wide angle.
To get even more wide you need a wider lens and a dome to get the best out of it or a wet lens.
A wet lens is quality related the lesser solution, but give you the option to change it under water as not always you encounter what you have planned.
But triplecheck if you can mount a INON wetlens with it's dome on your housing and especially check that it works without:
- zooming to get rid of vignetting
- soft corners
- degraded image quality

Chris

This anemonefish shot is the 12-50 with a wet wide angle fisheye lens, not very good in the corners.

http://www.scubatravel.com/photography/reviews/EM5flatportwetlens.html

The 12-50mm lens will fit in the 4 inch semidome port from Nauticam (for the 9-18mm lens) but seems not to be able to focus between about 35-50mm. It will give you more field of view than the flat port you currently have but can only be used at the wide end of the lens.

 

The 12-50mm lens will fit in the 4 inch semidome port from Nauticam (for the 9-18mm lens) but seems not to be able to focus between about 35-50mm. It will give you more field of view than the flat port you currently have but can only be used at the wide end of the lens.

I have used it a few times in this configuration but had no problems whatsoever except some chromatic aberrations that can be cleaned afterward. I found it more useful than behind the expensive and dedicated flat dome from Nauticam,,,

OK, so your 12-50 lens will focus fine throughout the range in the 4” semi-dome port? Interesting, we’ve had issues here with that.

Same for me. 12-50 is working fine in the 4" semidome throughout the range. It works with a diopter as well for the small stuff.

Good news, thanks for the feedback!

yes it will work fine and very practical with the Nauticam diopter adapter for the 4" dome port,,,

If I use this lens I now use it with the dome port and the very practical diopter adaptor for this port.

Also because my Macro button on the lens has stopped working ! (