4 replies to this topic

[betti154]

Hi Guys,

I've just realised that according to the Aquatica lens chart I should be using extension #18457 (67mm) with the 5D3, 17-40mm and 8" dome.

As I don't want to travel with yet another extension ring, can I'm wondering if I can stack the ones I already have and need to get a solution. With what I have, I can make a 63mm, 70mm or 75mm long stacked extension.

I'm guessing the 70mm solution will be the way to go, but my dome theory is a little rusty so looking for some advice.

thanks, damien

[Timmoranuk]

I don't shoot with an Aquatica but I frequently stack Nauticam extension rings. Upsides are a more flexible, weight saving solution when travelling and less cost (I should take my own advice as I have 2x20mm, 2x30mm, 2x40mm, 2x50mm, 2x60mm & 2x70mm). Downsides are a marginally heavier rig and an extra o-ring seal to worry about!

[betti154]

Thanks for the validation.

After a few beers I had the idea to jump in the pool and test out the setup. So that I can keep one extension for using on another rig, I tested the 75mm stack and it appeared to work fine. More vibrant subject matter is required, but I'm going with that for now. For Internet archive reference, it was one #18453 & one #18456.

Kind regards,
damien siviero

[Drew]

Damien
The 18457 is actually 54.5mm extension (67mm overall). You have to minus 13.5mm from overall length to get the extension length. I stacked 2 x 18453 (28.5mm) to get 57mm and it worked fine. I used the 18453s with the macro port with the 100L and extension tubes and extended accordingly.

[betti154]

Thanks Drew for the correction.

Seemed to work in the end, image quality didn't seem to be an issue with the stacked setup.