Housing Flange Distance

[DreiFish]

Trying to gather the distance from the camera lens mount to the front of the camera housings where different extension rings attach. This is for the purposes of calculating the right extension length for various lenses in different manufacturer's housings.

 

I'll kick things off with the Nauticam N120 housings, which I've measured at 58.8mm (let's round to 60mm). If you have one of these housings, could you measure the distance with a ruler please and contribute here?

 

Nauticam N120 - 60mm

Nauticam N100 - 26mm?

Marelux - 43mm?

Seacam - 40mm?

Sea & Sea - ?

Aquatica - ?

Isotta - ?

Ikelite - ?

 

End result will be a spreadsheet like this that I will share here for future reference:

 

[Isaac Szabo]

Isotta is 38mm (for Sony mirrorless at least).

 

Someone with a depth gauge measured N120 Nikon Z for me at 66mm. Is your 58.8mm measurement with a DSLR or mirrorless housing?

[Chris Ross]

The flange distance is different for Canon EF and RF as well as Nikon F and Z mount, the housings are designed so the same lens gear is used for DSLR lenses when mounted on the adapter for mirrorless cameras. 

 

The distances will be different depending on what camera manufacturer the housing is for.

[dentrock]

I just re-measured my Nauticam A7CR rig and it still came out at 28mm.

 

I also measured my Nauticam A7RV and that was 27mm; both using two rulers.

 

I suggest people measure their own rigs... to see if there's any variation. I noticed the tray position is not so precise, so could account for maybe 1mm.

 

Regardless, to make best use of these flange measurements, we will need EP measurements for various lenses (distance from aperture location as viewed from the front, to lens flange); and distance of optical centre behind dome port flange.

 

If you accept that the radius of the Nauticam 140 dome is 70mm, that distance is 7mm (or if you agree with old mate now departed), it's 69mm radius making the variation 6mm.

 

I'll volunteer an estimate of the EP for Sony 20-70 at 77mm, at 20mm (decreasing towards tele end).

 

I wish someone would estimate the EP for their Laowa 10! It's not hard to do! Within a couple of mm will be fine for now.

 

I have EPs for various E mount APS-C lenses, but not much interest in those.

[DreiFish]

On 7/13/2024 at 4:34 PM, Chris Ross said:

The flange distance is different for Canon EF and RF as well as Nikon F and Z mount, the housings are designed so the same lens gear is used for DSLR lenses when mounted on the adapter for mirrorless cameras. 

 

The distances will be different depending on what camera manufacturer the housing is for.

 

Interesting, Chris. I didn't realize they would be different in the same port size (n120). Anyway, my 58.8mm measurement is for the Nauticam Canon RF housings.

[fruehaufsteher2]

Just measured:

 

A7 IV (N100): 26mm

[Aquatica]

On 7/13/2024 at 10:22 AM, DreiFish said:

Trying to gather the distance from the camera lens mount to the front of the camera housings where different extension rings attach. This is for the purposes of calculating the right extension length for various lenses in different manufacturer's housings.

 

I'll kick things off with the Nauticam N120 housings, which I've measured at 58.8mm (let's round to 60mm). If you have one of these housings, could you measure the distance with a ruler please and contribute here?

 

Nauticam N120 - 60mm

Nauticam N100 - 26mm?

Marelux - 43mm?

Seacam - 40mm?

Sea & Sea - ?

Aquatica - ?

Isotta - ?

Ikelite - ?

 

End result will be a spreadsheet like this that I will share here for future reference:

 

I will speak with engineering and get back to you with the camera bayonet to housing flange distances for our verious housings.

[DreiFish]

13 hours ago, Aquatica said:

I will speak with engineering and get back to you with the camera bayonet to housing flange distances for our verious housings.

 

That would be awesome. Hope more manufacturers follow suit.

 

In the meantime, this is the table I've compiled so far: