Subal dome FE2 + wide lens without diopter

Hi

I'm considereing getting a Canon 14mm F2.8L mark 2 lens for use with my 5D in a subal housing. I use a FE2 dome port + 50mm extension. The lens won't allow the addition of the +2 diopter that Subal recommend to get full focusing on the lens.

My question: without the diopter, will I just lose a bit of the close-up focusing? If so, about how much - that is, roughly how close can I still focus?

Or can anyone suggest a way to add a diopter? Is it possible to get one made (maybe by my local optician), whch will fit in the gel filter holder at the rear of the lens?

What other choices do I have for a wide lens? I have the 17-40 but am not very happy with the softness in the corners. Will the 16-35 mark 2 perform better (and will it fit in the housing?)

Any advice will be much appreciated

cheers

Carol

Hi Carol,

I would expect the 14mm without a dioptre to have worse corner sharpness than your 17-40mm. If you can get one to test in a pool before buying that would be ideal.

Alex