Canon 8-15 on Sony APS-C cameras

Hi all,

I'm considering to not sell my Sony A6500 in it's Nauticam housing, but maybe add some more toys to my collection, more precisely a fisheye lens. And for compatibility to fullframe, I'd like to go for the Canon and not the Tokina, despite the price difference.

What I'm thinking about is adding a Metabones adapter and the Canon 8-15 in the Zen 100mm Domeport (the domeport I should receive tomorrow anyways). Now the issue I face is, that there is no port chart available for this (or I couldn't find it). However, there is for the Tokina 10-17. This would mean a 50mm adapter from N85 to N120, and then the domeport (according to an email from Zen that should work for the Tokina). Now, the Canon is a bit longer (83mm) than the Tokina (71mm). So far my understanding is, that the lens should be at a center point of the domeport. Guessing that the Tokina would be placed correct, the front element of the Canon should sit at the same point? So I guess I would ideally need to move the domeport 12mm. There is a 10mm extension ring available from Nauticam. What do you guys think, would the 50mm adapter with a 10mm extension work? Or maybe rather the 55mm adapter and the 10mm extension? Any ideas if the Nauticam zoom gear could work, or would I need to start 3D printing (yeah, more toys!)?
Does anyone by chance have the Canon 8-15mm on a Sony APS-C in a Nauticam housing and would share his port setup?

Thank you all and kind regards,
Fabian

According the the Nauticam port chart the Canon 8-15 needs 20mm more extension than the Tokina 10-17.  How to adapt this to your 100mm Zen dome port depends on which variety of dome port you have, in N120 there is the the DP-100 N120CR and N120T, which are setup exactly for the Canon and Tokina lenses respectively and have built in extension for those lenses. 

If you have a setup that works with the 10-17 you should be able to add a 20mm extension to use that with a Canon 8-15.

Hi Fabian,

The built in extensions for the Zen DP100 are 15mm (Tokina) and 22mm (Canon). According to the Zen recommendation, the additional extension hence should be 7mm. Maybe even a 20mm extension (as Chris and Nauticam suggest) may do it. You will see it yourself, when there is vignetting or not ...

Which DP100 did you get: N120 (= no built in extension), T-version (Tokina) or C-version (Canon)?

I am not familiar with Nauticam adapters/extensions for Sony APS-C systems, but had a quick look now in the port charts: the 50mm extension is for the 4.33" Acrylic Wide-angle Dome Port, not for Zen DP100. In case the extension is the same for Zen DP100 and the 4.33" port (there was a recent discussion on 4.33" and DP100 with Canon, you should have a look), the 55mm (maybe also the 60mm) adapter may be better. If I were you, I would ask at Zen...

Wolfgang

Hi both,

thank you for you input! I've got the Tokina version (got a good deal on a preowned one so I couldn't stop myself), so following the Zen logic, I'd need another 7mm, following the Nauticam Canon portchart logic, I'd need 20mm more. I'm gonna send Zen an email and see what they advise.
For both cases, I probably need a custom zoom gear...

Best,
Fabian

Maybe you should ask also Nauticam (Nauticam US are very competent and fast in feedback: https://www.nauticam.com/) about the zoomgear. As far as I understand the system, it should probably work with the Nauticam zoomgear, as long as you use a N85/N120 adapter with built in knob for zoomgear. When using lens mount adapters you operate the zoomgear via the knob that is located on the N85/N120 adapter, instead the knob on the housing ...

The difference in glassless adapters between EF/MFT and EF/Sony-E is 0,8mm (the pure adapters are 34,7mm (MFT) vs. 35,5mm (E)). Therefore you could use with the Tokina version:

34,7mm N85/N120 + 10mm N120 extension (or even 20mm): 2,2 mm (12,2 mm) too long,  should fit...

41,5mm N85/N120 adapter: - 1mm too short (= almost perfect)

In case you do not have yet the 10mm N120 extension, avoid it. It is very laborious to mount/dismantle...

=> Make a plan for yourself and better ask Nauticam before ordering...

Wolfgang

P.S.:  A bit later it came to my mind, that you should ask Nauticam in any case, whether the N85/N120 adapters are able to house the Metabones EF/Sony-E adapter that has more diameter on the side towards the camera. Probably yes, but who knows...

HI Wolfgang,

thanks, I've shot both Zen and Nauticam an email, lets see what they advise regarding these adapters.

Kind regards,
Fabian

For APSC I would recommend the Tokina 10-17mm it is useful to have a more narrow field of view and the lens is smaller more suitable to the small A6XXX bodies

Hi all,

Had a chat with Nauticam/Zen - really seems to difficult (or more, chances of failing in an expensive way seem quite high). And, I got a Tokina 10-17 for 180€, so that's the way forward.

Thank you guys for your help!

Best,
Fabian