10mm Laowa full frame lens.

[Architeuthis]

On 7/8/2024 at 10:39 PM, Phil Rudin said:

Regarding Sony FE  rectilinear lenses in a 180mm dome port you need to be careful about lens choice. 

 

Sony FE 16-35mm F/2.8 GM minimum focus is 28cm.

Sony FE 16-35mm F/2.8 GM II is 22.1cm

Sony FE 16-35mm F/4 PZ is 24cm

Tamron 17-28mm F/2.8 is 19cm

Sony FE 16-25mm F/2.8 is 18cm

 

For best results in the 180mm dome those with a minimum focus distance of 20cm or less work best with the GM II working pretty well also. I recently moved from the Tamron 17-28 F/2.8 to the Sony FE 16-25mm F/2.8 G. Image quality is every bit as good as the GM II underwater in the 180mm dome at half the cost. Looking back over more than thirty years of using 16-35mm lenses U/W I used the 16-24mm range over 95% of the time so will not be missing the 35mm end.

 

 

 

Does the Sony FE 16-25mm perform better compared to the 16-35mm GM II behind the 180mm domeport or just equal?

(For additional over the water use one may prefer to get the more expensive 16-35mm GM II)

[Chris Ross]

30 minutes ago, Isaac Szabo said:

 

Interesting. How accurate do you think your method was (ruler, calipers, depth gauge, etc)? It would be nice to know for sure since I make N100 RS13 ports. It's unfortunate that it's not the same for all their Sony FF housings. 

 

On this thread he claimed 27mm: 

 

It should be the same on all housings should it not?  This dimension would need to be constant to ensure that the focus and zoom gears will mesh with housing zoom mechanism, though the zoom gear on mine is 4mm thick by a quick measurement so it could be off by +/- 1mm or so and still mesh.  If you are trying to get the zoom knobs on adapters to mesh the tolerance I think would be tighter to work well maybe +/- 0.1mm tolerance to ensure the gears fully mesh?

 

Not the easiest distance to measure, on most housings you would need to use a straight edge laid across the port opening and measure from that to the flange.

[Isaac Szabo]

1 hour ago, Chris Ross said:

 

It should be the same on all housings should it not?  This dimension would need to be constant to ensure that the focus and zoom gears will mesh with housing zoom mechanism, though the zoom gear on mine is 4mm thick by a quick measurement so it could be off by +/- 1mm or so and still mesh.  If you are trying to get the zoom knobs on adapters to mesh the tolerance I think would be tighter to work well maybe +/- 0.1mm tolerance to ensure the gears fully mesh?

 

Not the easiest distance to measure, on most housings you would need to use a straight edge laid across the port opening and measure from that to the flange.

 

I assumed it would be the same until someone said it wasn't, which makes no sense to me for reasons you mention and others. 

 

Yep, for accuracy you need something that can span the port mount opening like this:

 

 

Or as you mention you can lay a straight object across it and subtract its thickness:

 

[Phil Rudin]

8 hours ago, Architeuthis said:

 

Does the Sony FE 16-25mm perform better compared to the 16-35mm GM II behind the 180mm domeport or just equal?

(For additional over the water use one may prefer to get the more expensive 16-35mm GM II)

Architeuthis, I don't have access to the Sony FE 16-35mm F/2.8 II GM so I have not compared the two. Howeverthe Sony FE 16-25mm F/2.8 G  it is the best lens in the range that I have used to date. Based on feedback from folks I know in the industry the 16-35mm F/2.8 II GM in the 180mm port does not outperform the 16-25 except for the extra focal length. Also I own the Sony FE 20-70mm F/4 also a G lens and would chose it over 16-35 if I want extra length underwater, I also prefer this lens above water. These two lenses cost about the same as the GM lens and both work well in the 180mm dome. These lenses are part of my travel kit along with the Laowa 10mm and 140mm or 230mm port.  

 

Chris, The Canon RF 15-30mm is not a lens I have tested in the 180mm port however I have been told by friends in the industry that it does not preform as well in the 180mm port as the close focusing Sony lenses in the same focal range.

 

Dreifish, The Sony FE 24-50mm F/2.8 G has been added to the latest Nauticam update (7/9/24) for Sony FF housings from A7 II forward. It will pare with WACP-C and a verity of ports but WWL-C is not listed. 

 

The Nikon's 13mm fisheye is a great lens but it is not light at over two pounds before the conversion so I don't think the difference V 8-15 in 140 port will be that big a difference. For someone who uses fisheye 90% of the time rather than 10% this may be a more attractive offering. Also I doubt that this lens can be made to focus much above 15 FPS.

 

SAGA makes custom extensions so they may be able to offer something in the 12/13 range. The port adapters for WACP-1 are also offered for a number of housings besides Nauticam. 

 

 

[dentrock]

18 hours ago, Chris Ross said:

 

It should be the same on all housings should it not?  This dimension would need to be constant to ensure that the focus and zoom gears will mesh with housing zoom mechanism, though the zoom gear on mine is 4mm thick by a quick measurement so it could be off by +/- 1mm or so and still mesh.  If you are trying to get the zoom knobs on adapters to mesh the tolerance I think would be tighter to work well maybe +/- 0.1mm tolerance to ensure the gears fully mesh?

 

Not the easiest distance to measure, on most housings you would need to use a straight edge laid across the port opening and measure from that to the flange.

It was a "dirty" measurement, made only for the purpose of calculating required extensions for various off-chart applications, so maybe within 1-2mm which is fine for that purpose.

 

Regarding possible diff measurements for Nauticam / Sony rigs, note that they list 3 diff port charts for Sony N100 ports. Go figure! I have been using the A7RV etc chart and ignoring the others, because it's the most comprehensive.

 

Regarding Chris' comment about Nauticam gear meshing, note that although the gears themselves have only a very small tolerance for misalignment (max approx 1mm) there is a bit of variation possible depending on where you mount the gear on the lens.

[ScubaBC]

Stumbled upon this thread while Googling the new Laowa 10mm and thought I would pop in... I can't contribute to the tech talk, but it's all very helpful!  I have ordered the lens and just waiting for it to arrive (back ordered here in Canada).  I am shooting with a Sony A7Siii in an Aquatica Housing.  I have the 8" acrylic dome and am currently using the Sony 16-35mm F4 lens.  I am going to pair the Laowa with my 8" dome (shades removed) and my 25mm extension ring from my mini-macro port, so hopefully this works well!

[Phil Rudin]

14 minutes ago, ScubaBC said:

Stumbled upon this thread while Googling the new Laowa 10mm and thought I would pop in... I can't contribute to the tech talk, but it's all very helpful!  I have ordered the lens and just waiting for it to arrive (back ordered here in Canada).  I am shooting with a Sony A7Siii in an Aquatica Housing.  I have the 8" acrylic dome and am currently using the Sony 16-35mm F4 lens.  I am going to pair the Laowa with my 8" dome (shades removed) and my 25mm extension ring from my mini-macro port, so hopefully this works well!

You may want to contact Aquatica direct because they have the lens and appear to be making custom extensions for all three large ports glass and acrylic.  

[ScubaBC]

8 minutes ago, Phil Rudin said:

You may want to contact Aquatica direct because they have the lens and appear to be making custom extensions for all three large ports glass and acrylic.  

Yes, I have corresponded with them and it sounds like it will be a whole new dome port with no extension and no shades and I can't drop that kind of money just yet.  If it doesn't work well with the current combo I might just turn around and sell it.  From what I am reading on here the 25mm extension I have just might work.

[Phil Rudin]

I am currently shooting Marelux housings for A7R V and A1 using 20mm extension for the 230mm and MS 12 inch ports and 35mm for the 140mm dome with shade removed. Not sure how this translates to Aquatica but 25mm sounds close.    

[DreiFish]

3 hours ago, ScubaBC said:

Yes, I have corresponded with them and it sounds like it will be a whole new dome port with no extension and no shades and I can't drop that kind of money just yet.  If it doesn't work well with the current combo I might just turn around and sell it.  From what I am reading on here the 25mm extension I have just might work.

If Aquatica is making a custom dome for it with no extension, then 25mm extension will probably be way too long and vignette. Sounds like the flange distance (distance between the lens mount on the camera and the front of the housing) on the Aquatica housings might be closer to the Nauticam N120 distance of 60mm. On Nauticam N120, you need either no extension or a 5mm extension that doesn't exist. Longer extensions like 20mm don't work because it vignettes.

 

We could give you more advice if you just measure the flange distance on your Aquatica housing.

[dentrock]

So I have just got my Laowa 10. And since no-one else has volunteered an EP measurement, here is my estimate: 

 

61mm from lens flange to apparent position of diaphragm, when viewed from the front of the lens (just below the blue ring on the lens).

 

Others should check this and let us know what they think, as I found it reasonably difficult to estimate for this lens; but I expect my figure to be within 2mm.

 

Now, using EP=61mm and a flange distance of 28mm for my Sony A7CR (use 27mm if you like); plus a figure of 7mm for location of optical centre behind dome flange for Nauticam 140 FE dome (use 6mm if you like), an extra 5mm extension is theoretically required plus the N100 to N120 35mm adapter to align the EP with that dome's optical centre.

 

Since there is no 5mm ext available, try none, which may reduce any vignetting.

 

Or try a 40mm adapter if there is one and you can be bothered....

 

For the Nauticam 180 WA dome (and using a figure of 25mm from old mate now departed for location of optical centre behind that dome's flange), required extension for Sony mirrorless is theoretically 23mm (plus the 35mm adapter).

 

These figures are starting points only, and do not take account of any vignetting (not tested yet).

 

[Chris Ross]

8 hours ago, ScubaBC said:

Yes, I have corresponded with them and it sounds like it will be a whole new dome port with no extension and no shades and I can't drop that kind of money just yet.  If it doesn't work well with the current combo I might just turn around and sell it.  From what I am reading on here the 25mm extension I have just might work.

Seems odd they are talking about making it with no shades - there's no mention of having to remove the shades with a full frame fisheye lens.  No extension also doesn't sound right, presumably it must have some built in extension.  If you compare the 10mm laowa lens to to the Canon 8-15 with Metabones - both should have the entrance pupil right up front, so the difference in length between the two should be close to the difference in extension requirements.  The difference is (83+24) - 73mm = 34 mm

 

The Canon 8-15 takes a 48462 39.5mm extension with the glass dome while it takes the a 48461 with the acrylic dome.  The 48461 extension dimension seems to be a state secret, I can't find it!  but looking at the port chart the acrylic requires approx 10mm more extension so assume the extension needed is 49.5mm.  This gives an an extension of 49.5 - 34 = 15.5mm so very close to the 16.5mm ring and the lens would likely be too far forward to use without extension - just the dome.  Seems like it would be worth checking with a 48456 - 16.5mm extension to see if it vignettes.  Keep in mind this is a ball park estimate that indicates it's worth trying and it seems to indicate the 20mm might be too long.  It also tends to confirm why Aquatica are working on a dedicated dome.

[Chris Ross]

58 minutes ago, dentrock said:

So I have just got my Laowa 10. And since no-one else has volunteered an EP measurement, here is my estimate: 

 

61mm from lens flange to apparent position of diaphragm, when viewed from the front of the lens (just below the blue ring on the lens).

 

Others should check this and let us know what they think, as I found it reasonably difficult to estimate for this lens; but I expect my figure to be within 2mm.

 

Now, using EP=61mm and a flange distance of 28mm for my Sony A7CR (use 27mm if you like); plus a figure of 7mm for location of optical centre behind dome flange for Nauticam 140 FE dome (use 6mm if you like), an extra 5mm extension is theoretically required plus the N100 to N120 35mm adapter to align the EP with that dome's optical centre.

 

Since there is no 5mm ext available, try none, which may reduce any vignetting.

 

Or try a 40mm adapter if there is one and you can be bothered....

 

For the Nauticam 180 WA dome (and using a figure of 25mm from old mate now departed for location of optical centre behind that dome's flange), required extension for Sony mirrorless is theoretically 23mm (plus the 35mm adapter).

 

These figures are starting points only, and do not take account of any vignetting (not tested yet).

 

Thanks for the analysis, I think from what Massimo published previously the max field from the centre of curvature is about equivalent to a 14mm rectilinear lens so the 10mm would need to sit forward of the centre of curvature if is not to vignette.

 

You could probably test adding 5mm extension for vignetting by sliding the camera back on it's mounting plate while sitting in the housing.

[dentrock]

Notes on vignetting (on land), applying my above figures:

 

 1. With 35mm adapter and no other extension plus 140 dome, vignetting is slight - say, 2-3mm of shade visible top and bottom. This could be easily cropped in post - or I could remove the shade.

 

At this stage, I prefer to keep the shade and try this combo in water, in about 3 weeks or so.

 

2. With 180 dome plus 35 adapter plus 20mm extension, vignetting is substantial - shade plus internal port. The shade is fixed, and I doubt removing the 20mm ext would fix things (and that much mis-alignment would seriously compromise the corners). I won't be testing this in water any time soon.

 

3. With 20mm extension plus 35 adapter and using the 8.5 inch acrylic dome, vignetting is moderate (in between the above two options). The shade can be removed but this won't quite remove the slight corner cutoff. which I would put up with.

 

Regarding this dome's calibration, I think 121 said the optical centre was 26mm behind the flange, so much the same as for the 180 - I can't confirm this figure.

 

Someone else to advise and confirm????

 

Regrettably, if I want to use both the 20-70 and the 10 behind one dome on a trip, the 8.5" with shade removed is the only solution, unless I buy yet another larger dome, which really, really, isn't going to happen.

[DreiFish]

7 hours ago, Chris Ross said:

Seems odd they are talking about making it with no shades - there's no mention of having to remove the shades with a full frame fisheye lens.  No extension also doesn't sound right, presumably it must have some built in extension.  If you compare the 10mm laowa lens to to the Canon 8-15 with Metabones - both should have the entrance pupil right up front, so the difference in length between the two should be close to the difference in extension requirements.  The difference is (83+24) - 73mm = 34 mm

 

The Canon 8-15 takes a 48462 39.5mm extension with the glass dome while it takes the a 48461 with the acrylic dome.  The 48461 extension dimension seems to be a state secret, I can't find it!  but looking at the port chart the acrylic requires approx 10mm more extension so assume the extension needed is 49.5mm.  This gives an an extension of 49.5 - 34 = 15.5mm so very close to the 16.5mm ring and the lens would likely be too far forward to use without extension - just the dome.  Seems like it would be worth checking with a 48456 - 16.5mm extension to see if it vignettes.  Keep in mind this is a ball park estimate that indicates it's worth trying and it seems to indicate the 20mm might be too long.  It also tends to confirm why Aquatica are working on a dedicated dome.

 

8 hours ago, dentrock said:

So I have just got my Laowa 10. And since no-one else has volunteered an EP measurement, here is my estimate: 

 

61mm from lens flange to apparent position of diaphragm, when viewed from the front of the lens (just below the blue ring on the lens).

 

This sounds about right -- I had estimated it at 65mm based on my extension ring testing with the 140mm dome and Matty Smith custom 427mm dome (both of which are full hemispherical domes). Based on Phil's tests earlier in this thread, I didn't try the 180mm dome because it's not a full hemisphere and has a built in 10mm extension and a more narrow field of view, so I don't think it would be ideal. I've updated my chart here (ignore the I/P/FD figures, they're just made up to arrive at the lens-to-flange distance of 61mm):

 

 

 

8 hours ago, dentrock said:

 

Now, using EP=61mm and a flange distance of 28mm for my Sony A7CR (use 27mm if you like); plus a figure of 7mm for location of optical centre behind dome flange for Nauticam 140 FE dome (use 6mm if you like), an extra 5mm extension is theoretically required plus the N100 to N120 35mm adapter to align the EP with that dome's optical centre.

 

Since there is no 5mm ext available, try none, which may reduce any vignetting.

 

Or try a 40mm adapter if there is one and you can be bothered....

 

This matches my results using no extension on the Nauticam N120 housing (for Canon R5C). 5mm extension might theoretically work better if it were available, but 20mm vignettes, and I suspect 10mm would also. I have a problem getting my Nauticam N120 10mm extension ring (v2) to work with my domes and housing though, so no way to test.

 

(There is no 40mm n100-n120 adapter)

 

8 hours ago, dentrock said:

 

For the Nauticam 180 WA dome (and using a figure of 25mm from old mate now departed for location of optical centre behind that dome's flange), required extension for Sony mirrorless is theoretically 23mm (plus the 35mm adapter).

 

These figures are starting points only, and do not take account of any vignetting (not tested yet).

 

 

The 180mm dome has a built in 10mm extension that narrows in. This might work on the n100 housings with a 20mm n100 extension because of the shorter housing flange distance. But as far as I know, there is no 20mm n100 extension ring -- the shortest is 30mm. I suspect the 30mm + 180mm port would vignette worse than the 35mm n100-n120 conversion ring + 140mm dome. 

 

7 hours ago, Chris Ross said:

You could probably test adding 5mm extension for vignetting by sliding the camera back on it's mounting plate while sitting in the housing.

 

This is a great idea, Chris 🙂

 

6 hours ago, dentrock said:

Notes on vignetting (on land), applying my above figures:

 

 1. With 35mm adapter and no other extension plus 140 dome, vignetting is slight - say, 2-3mm of shade visible top and bottom. This could be easily cropped in post - or I could remove the shade.

 

At this stage, I prefer to keep the shade and try this combo in water, in about 3 weeks or so.

 

I got the same results with the 140mm dome and no extension on Nauticam n120 (Canon R5C) -- the lens hood is visible at the top and bottom of the image. But you can get rid of that by removing the dome.

 

6 hours ago, dentrock said:

 

2. With 180 dome plus 35 adapter plus 20mm extension, vignetting is substantial - shade plus internal port. The shade is fixed, and I doubt removing the 20mm ext would fix things (and that much mis-alignment would seriously compromise the corners). I won't be testing this in water any time soon.

 

There's no advantage in image quality from using the 180mm dome over the 140mm dome, and you lose field of view/get vignetting. This is because the 180mm dome is not a true hemisphere, and Massimo has estimated that it only really covers fields of view down to about a 16mm focal length. The Laowa 10mm needs a fisheye dome port like the 140mm or 230mm domes. 

 

6 hours ago, dentrock said:

 

3. With 20mm extension plus 35 adapter and using the 8.5 inch acrylic dome, vignetting is moderate (in between the above two options). The shade can be removed but this won't quite remove the slight corner cutoff. which I would put up with.

 

The 8.5 inch acrylic dome is also not a full hemisphere, so it's a compromise in terms of using it with such a wide lens. I suspect you'd get better optical results with the 140mm dome. 

 

6 hours ago, dentrock said:

 

 

Regrettably, if I want to use both the 20-70 and the 10 behind one dome on a trip, the 8.5" with shade removed is the only solution, unless I buy yet another larger dome, which really, really, isn't going to happen.

 

Have you tried using the 20-70 with the 140mm dome? The 20-70 has a 250mm MFD, so you will lose the ability to focus totally inside the dome at infinity, but that may not matter in practice?

 

If the 20-70 doesn't work with the 140mm dome, your best option will unfortunately be to step up to the 230mm dome, which is closer to a true hemisphere and should support the 10mm extended field of view (especially without the dome hood).

[ScubaBC]

This is about the only video I can find using this lens underwater.  This is an ikelite housing with a 20mm extension.  Looks pretty good too me.  I have to figure out what to do with my tripod plate on the bottom of my housing as it sticks out a bit and won't allow the dome port to attach with such a small extension.  I might have to try 3D printing a new plate.

 

 

[Phil Rudin]

As I have said on several occasions I do old-school testing and basically come up with the same results without all the math. First I have said back several pages the 180mm dome is a buster Laowa 10mm,  just not worth the effort. 

 

For travel with both the Sony FE 20-70mm and the Laowa 10mm F/2.8 the best two choices are the 140mm port with the shade removed and the 230mm port with shade. Any of the Matty Smith domes also work well. Port extension varies depending on the housing brand you are using and the available extension lengths. Regarding Nauticam the 140mm & 230mm ports are N120 and the shortest N100 to N120 port adapter is the expensive 25mm specifically designed for use with the WACP-2 and Sony FE 14mm F/1.8 lens. The next choice is the recommended 35.5mm port adapter which should vignette. With the Marelux housing I am using 35mm's of extension a 20mm + 15mm. The closest equivalent in Nauticam would be an N100 to N120 15mm extension which does not exist. Best choice will be the over $700.00 N100 to N120 25mm with some vignetting or to contact SAGADIVE.com and have a custom extension in the 15mm range made which will cost less than the NA-25mm option. Please feel free to correct me if my Nauticam conversion is wrong.

 

Photos are the Sony FE 20-70mm in the Marelux 140mm dome with shade. The block with the currency is closest focus at 70mm. The pool light is 20mm at closest focus. The steps and split are both at 20mm. I am using 75mm's of extension with the Marelux housing for these test photos.  Marelux setup with the Laowa 10mm and 35mm's of extension.

 

null

Edited July 18 by Phil Rudin

[ScubaBC]

Quote

For travel with both the Sony FE 20-70mm and the Laowa 10mm F/2.8 the best two choices are the 140mm port with the shade removed and the 230mm port with shade. Any of the Matty Smith domes also work well.

 

The Aquatica 8" acrylic dome seems to be in between those two as it's 8" or 203 mm.  When I get the lens or even right now with just my camera in the housing, what measurements would be helpful for other Aquatica users who may also stumble upon this thread looking for how to best utilize this lens?

[Phil Rudin]

So for Aquatica 230mm/9.25" and 152mm/6" ports the extension is 39.5mm (#48462) when using the Canon 8-15mm Fisheye zoom with adapter. 

 

For Marelux using the 230mm and 140mm ports the extension is 40mm for the Canon 8-15mm with adapter, very close to the Aquatica.

 

With Nauticam using 230mm and 140mm ports the extension is 65.5 or N100 to N120 35.5 + N120 30mm extension II using the Canon 8-15mm with adapter.

 

Unfortunately Aquatica does not list the length of extension #48461 used with the eight inch acrylic port for the same lens.

 

Extrapolate from this what you will or you can compare other like lenses, ports and extensions.

 

Also be aware that the Aquatica 8" acrylic is not a fisheye type port so likely to be less forgiving. 

 

[dentrock]

7 hours ago, Phil Rudin said:

For travel with both the Sony FE 20-70mm and the Laowa 10mm F/2.8 the best two choices are the 140mm port with the shade removed and the 230mm port with shade. Any of the Matty Smith domes also work well. Port extension varies depending on the housing brand you are using and the available extension lengths. Regarding Nauticam the 140mm & 230mm ports are N120 and the shortest N100 to N120 port adapter is the expensive 25mm specifically designed for use with the WACP-2 and Sony FE 14mm F/1.8 lens. The next choice is the recommended 35.5mm port adapter which should vignette. With the Marelux housing I am using 35mm's of extension a 20mm + 15mm. The closest equivalent in Nauticam would be an N100 to N120 15mm extension which does not exist. Best choice will be the over $700.00 N100 to N120 25mm with some vignetting or to contact SAGADIVE.com and have a custom extension in the 15mm range made which will cost less than the NA-25mm option. Please feel free to correct me if my Nauticam conversion is wrong.

 

Photos are the Sony FE 20-70mm in the Marelux 140mm dome with shade. The block with the currency is closest focus at 70mm. The pool light is 20mm at closest focus. The steps and split are both at 20mm. I am using 75mm's of extension with the Marelux housing for these test photos.  Marelux setup with the Laowa 10mm and 35mm's of extension.

This is very helpful Phil! Many thanks.

I had assumed the 20-70 would not focus close enough to be worth the trouble with the smaller 140 dome, so good news it can be used with the 20-70 and 10.

I have the 25mm adapter and will try it with the 10.

Thanks again.

[dentrock]

9 hours ago, DreiFish said:

The 180mm dome has a built in 10mm extension that narrows in.

I think 121 said the 'built-in' ext was 25mm, with the optical centre still being a further 25mm behind the flange.

[Chris Ross]

6 hours ago, Phil Rudin said:

So for Aquatica 230mm/9.25" and 152mm/6" ports the extension is 39.5mm (#48462) when using the Canon 8-15mm Fisheye zoom with adapter. 

 

For Marelux using the 230mm and 140mm ports the extension is 40mm for the Canon 8-15mm with adapter, very close to the Aquatica.

 

With Nauticam using 230mm and 140mm ports the extension is 65.5 or N100 to N120 35.5 + N120 30mm extension II using the Canon 8-15mm with adapter.

 

Unfortunately Aquatica does not list the length of extension #48461 used with the eight inch acrylic port for the same lens.

 

Extrapolate from this what you will or you can compare other like lenses, ports and extensions.

 

Also be aware that the Aquatica 8" acrylic is not a fisheye type port so likely to be less forgiving. 

 

The 48461 should be about 10mm longer than the 48462 so about a 49-50mm extension.  This is based upon the difference in recommended extensions between the acrylic and glass port

[DreiFish]

1 hour ago, dentrock said:

I think 121 said the 'built-in' ext was 25mm, with the optical centre still being a further 25mm behind the flange.

 

Could be, I was just guestimating based on my recollection of what the 180mm dome looks like (mine is sitting packed in a closet) and the 10-15mm shorter extension Nauticam recommends in its port chart when using the 180mm dome instead of the 140mm or 230mm domes which don't have any protrusion at the back. In any event, the 180mm dome is definitely not anywhere near a full hemisphere like the 140mm or 230mm domes.

 

1 hour ago, dentrock said:

This is very helpful Phil! Many thanks.

I had assumed the 20-70 would not focus close enough to be worth the trouble with the smaller 140 dome, so good news it can be used with the 20-70 and 10.

I have the 25mm adapter and will try it with the 10.

Thanks again.

 

The pictures Phil posted look promising in terms of the 20-70s performance with the 140mm dome. Sounds like a potent travel combination together with the Laowa 10mm.

 

6 hours ago, Phil Rudin said:

So for Aquatica 230mm/9.25" and 152mm/6" ports the extension is 39.5mm (#48462) when using the Canon 8-15mm Fisheye zoom with adapter. 

 

For Marelux using the 230mm and 140mm ports the extension is 40mm for the Canon 8-15mm with adapter, very close to the Aquatica.

  

 

 

 

8 hours ago, ScubaBC said:

 

The Aquatica 8" acrylic dome seems to be in between those two as it's 8" or 203 mm.  When I get the lens or even right now with just my camera in the housing, what measurements would be helpful for other Aquatica users who may also stumble upon this thread looking for how to best utilize this lens?

 

Based on this, I would guestimate the Aquatica lens-mount to front of housing 'flange' distance to be around 40mm too. Below chart may be useful when converting port extensions from one housing manufacturer to another.

 

 

 

So probably the extension needed for Aquatica is similar to Marelux -- i.e. 20 to 25mm. At least I'd take that as a starting point for fine-tuning.

 

9 hours ago, Phil Rudin said:

Port extension varies depending on the housing brand you are using and the available extension lengths. Regarding Nauticam the 140mm & 230mm ports are N120 and the shortest N100 to N120 port adapter is the expensive 25mm specifically designed for use with the WACP-2 and Sony FE 14mm F/1.8 lens. The next choice is the recommended 35.5mm port adapter which should vignette.

 

N100 + 35.5mm port adapter should produce the same flange distance as the n120 housings with no adapter, or at least within 1-2mm. This combination only vignettes slightly with the 140mm Nauticam dome at the top and bottom because of the dome hood, which is designed to accommodate a fisheye lens's more limited vertical field of view. Without the dome shade, there's no vignetting. With the dome shade on the left, no dome shade on the right. Both with Nauticam R5C (n120) housing and no extension.

 

 

 

 

9 hours ago, Phil Rudin said:

 

With the Marelux housing I am using 35mm's of extension a 20mm + 15mm. The closest equivalent in Nauticam would be an N100 to N120 15mm extension which does not exist.

9 hours ago, Phil Rudin said:

 

Best choice will be the over $700.00 N100 to N120 25mm with some vignetting or to contact SAGADIVE.com and have a custom extension in the 15mm range made which will cost less than the NA-25mm option. Please feel free to correct me if my Nauticam conversion is wrong.

 

Something seems strange about this Phil. The Nauticam N100 equivalent to a 35mm extension on Marelux (i.e. total extension from lens flange of 40mm + 35mm = 75mm) would be 75mm - 26mm (Nauticam n120 flange distance) = ~50mm of total extension. That would be the 35.5mm n100 to n120 adapter + a 15mm extension ring. I've tried the a similar combination on Nauticam N120 (a 20mm adapter) and you get heavy vignetting. I doubt that vignetting would disappear by moving the lens closer only 5mm.. I suspect you need more than that. So it's interesting that there's no vignetting with your set-up on Marelux. Perhaps the Marelux lens mount to front of housing flange distance is closer to 30mm than the 40mm we've been estimating? Could you measure this?

Edited July 19 by DreiFish

[Aquatica]

🤓 Our new dome ports for the Laowa 10mm lens will be a one piece design construction, no extension ring required.

 

This was the best design option to ensure this lens was in the best optical position in relation to the dome and get no vignetting with the wing shades removed(shades can be installed when using other lens) 😊

 

You can see from the pictures of our 9.25 glass ring with the dome removed, the ring is machined out at a sharp angle starting directly from the bottom of the rings, this design ensures no vignetting.

 

These ports are quite buoyant so we are working on a counterweight solution😉

 

8” acrylic dome port:

 

8” glass dome port:

 

9.25” glass dome port:

 

 

😀No secret on our 48461 Extension ring:

Overall length-  2.310 inches  or 58.6mm

Effective length- 1,820 inches or 46.2mm

Edited July 19 by Aquatica

[Chris Ross]

1 hour ago, Aquatica said:

 

 

😀No secret on our 48461 Extension ring:

Overall length-  2.310 inches  or 58.6mm

Effective length- 1,820 inches or 46.2mm

Thanks for the update, I couldn't find it anywhere on line, it's not on the extension port data pdf and no photos or specs on the websites.