Hi all,

Can anyone using this optical dome port tell me what length extension they are using, with which make of housing and with what effect please?

Thanks
Alex

After a lot of to-ing and fro-ing on what are the recommended extensions for my Subal (and soon to be Nauticam with Subal mount ports) the latest advice I've got from Ryan at Reef Photo is that the recommended extensions for the Tokina 10-17 are 15mm with the 10-17 alone and 33mm with the 10-17 on my Kenko 1.4X teleconverter. This is a bit different to the advice I received when I first ordered my Zen some back in December 09 which was that an extension was not needed with the 10-17 alone.

I have tried the 10-17 with 1.4X teleconverter and 33mm extension and was happy with the results. I've only used the 10-17 alone with no extension and was happy with those results too. I haven't tried the 10-17 alone with a 15mm extension yet as the extension is in the mail somewhere between here and the USA, my Nauticam hasn't been delivered yet, none of these bits will fit on the Aquatica housing I'm trialling at the moment and my wife has taken over my Subal housing and won't give it back!!

Thanks Gudge for this,

We tried this port alone with the Nauticam NA-D90 and Tokina 10-17mm but it won't fit. It seems like it needs at least a 20mm extension to fit into the port. Not sure how this will translate onto the NA-7D but I'd imagine the same story.

Alex

For the 10-17, you need the 20mm locking extension for the Zen 100mm - on any Nauticam housing.

Adding the 1.4x to the 10-17, you'll need a longer extension... I haven't had a chance to measure it yet.

I just tried the 4" Zen dome on my Subal with the tokina 10-17 and 15mm extension ring - same ring as if I was using the 8" Subal dome. Worked great!

Phil

Just to add another question here- either for Alex or Chris. I have the Zen 100mm dome for Subal (type 4) and am going to get a Nauticam 7D housing. Am I going to be able to fit this dome on with a 20mm or 15mm extension. ie can I use an extension and an adapter somehow?

Fergus

Hi Fergus,

It seems to me that you have two choices, You can either setup so you have the Zen port attached to a Nauticam 'Subal 4th Generation to Nauticam adapter' attached to a Nauticam 20mm extension ring attached to your housing.

Alternatively, you can have the Zen port attached to a Subal 4th generation extension ring attached to a Nauticam 'Subal 4th generation to Nauticam adapter' attached to the housing.

Not sure which setup would be optically ideal, I'd be happy to hear Chris's thoughts on this.

Alex

Thanks Alex, just wanted to check it would actually be possible. I'm guessing that providing the distances are right either option would work well. I guess I'll go for whatever's cheapest!

If you've already got the Subal 15mm extension, then you can just get the Nauticam adapter. This seems a good choice if you want to use other Subal ports since you'll also need the adapter for them.

If the Zen 100 is the only Subal port you want to use... you might be better off converting it to a Nauticam mount. Then you can dispense with the adapter. You'd still need the Nauticam 20mm locking extension, but you may want that for other port/lens combinations anyway. You or Alex can PM me for details about how to do this.

Chris,

Do you know why we need to use extension ring for Zen port "specially crafted" for Nauticam? Is it perfect optical solution? I'm not sure now ...
Another way - Nexus 4" FE-port with adapter - is 1,5 times less expensive ...

Regards,
Vladislav

I can't speak to Nexus pricing, but for clarification:

No extension ring is needed for a Nikon 10.5 DX Fisheye on a Nauticam Housing w/ DP-100

Nauticam Extension Ring 20 is needed for Tokina 10-17.

Ryan, do you have information for pupil entrance point of Tokina AT-X 107? Is it equals to focusing point of DP-100 with 20mm-ring? Could you please share any test images for NA-D90 + DP100?