Hi Everybody,

I just bought a fisheye dome port for my Sea&Sea Dx-70 Housing to use with the Nikkor 12-24 .Sea& Sea recommends this port for this lens,but after reading the articles about dome ports here at wetpixel i figured out that my lens is too close to the port glass,has any one taken photographs with this setup,or do someone hase something to recommend.(Diopters...etc).

By the way I am writing to you from Turkey / Istanbul,we are leaving for Sipadan on friday . I realy would appreciate your help.

Thanks Everybody

Some systems require extension rings. These move the port out farther away from the face of the lens. Most manufacturers provide these in varying sizes. I'd email Sea & Sea and ask what they recommend. They might claim that their port is the right one, but fail to mention the extension ring requirement.

Joe

When I use that lens w/ Sea & Sea's fisheye dome, I use EXR-40, even though the recommendation is for no extension.

Hi ,

Thank you for your prompt and use ful reply's. On the Sea&Sea sistem chart the 12-24 is used without the extension ring (in case of the big fisheye dome port which is the one i have).But the lens is nearly 3 cm to the glass... isnt that too close ? But for the compact dome port they recommend the sx extension ring. I also have the extension ring 40 .Should i risk to experiment with it? And what sould look for in my images to tell if something is wrong or not ?

Thank you all for your help...

I doubt Sea & Sea will be any help.

You can jump in a pool and see for yourself what you prefer. I would compare:

Vignetting- Black corners where the dome shade shows up in the frame
Corner Sharpness- Shoot a tile pattern, or take down a grid chart.

These should be taken at 12mm, fairly stopped down. Corner softness will be more evident at closer subject distances.