Hello Waterpixel Community,

 

I have a Spring trip planned to Anilao and Malapascua.  I shoot a Canon R5, and will take my RF100 for macro at Anilao, but Malapascua is a little more difficult to plan for given travel weight restrictions.  I have an 8-15mm fisheye, but think this might not have enough reach for the sharks, and I also don't want 50 divers in every frame 🙂. My 14-35mm with 230mm dome is just too big and heavy. 

 

I was looking at lens options and see that Canon makes an RF 35mm macro that will fit in my 140mm fisheye dome port.  Have any of you had experience with this lens underwater?  I was thinking it would work well for sharks, but also be nice for clownfish and some larger macro critters.

 

Any feedback on this lens, or other recommendations would be much appreciated.

 

Thank you.

The min focus distance for this lens is 170mm, given its dimensions and the size 0f the 140mm dome at 0.5x it will be focusing right on the dome, so I expect that the maximum practical magnification might be around 0.3x , so filling the frame with a 120mm long subject on the horizontal axis of the sensor.  You could also consider a 1.4x to add to your 8-15 which would give you 21mm focal length, about the same field of view on the horizontal field as a 16mm rectilnear lens

That's a lens I'd love to have for my Sony as a general / all purpose lens.

Normal focal length macros work fine behind the 140 dome (eg Sony 50 and Zeiss 50). Have also used Nikkor 60 in the distant past with a small dome.

 

Assuming you are talking Nauticam, the optical centre is about 6-7mm behind the 140 dome port face. You can estimate the EP for the lens (distance from lens mount flange to apparent location of diaphragm when viewed from the front), and having measured the distance from the lens flange to the housing port flange you can see what if any extension you will need. I don't know the Canon details, and I don't know if you need to use an adapter with your dome.

 

With Sony FF, a 25mm adapter and no other extension works well, given a lens flange to port flange distance of 26-27mm. EPs for the above lenses are approx 43 and 48mm respectively. Misalignment with this combo is -3 (too long) for the Sony and +2 (not long enough) for the Zeiss. But bear in mind EPs can move as you focus close.

 

Yours will be shorter I think. Macros / normal FOV lenses are pretty forgiving of inexact alignment.

 

You can also use a 35 with a flat port, but the central area of sharpness will be disappointingly small.

9 hours ago, Chris Ross said:

The min focus distance for this lens is 170mm, given its dimensions and the size 0f the 140mm dome at 0.5x it will be focusing right on the dome, so I expect that the maximum practical magnification might be around 0.3x , so filling the frame with a 120mm long subject on the horizontal axis of the sensor.  You could also consider a 1.4x to add to your 8-15 which would give you 21mm focal length, about the same field of view on the horizontal field as a 16mm rectilnear lens

Thank you, Chris.  I'll think more on the 1.4x.  I'm less concerned with the macro working distance than the performance on sharks in low ambient light.  I wonder if the 35mm focus hunts in those conditions.  I also had a thought that maybe I could run my 14-35 in the 140mm dome, but fix it at 35mm.  I'll have to compare the 2 lens dimensions. 

 

Anyone tried this in real life?

8 hours ago, dentrock said:

That's a lens I'd love to have for my Sony as a general / all purpose lens.

Normal focal length macros work fine behind the 140 dome (eg Sony 50 and Zeiss 50). Have also used Nikkor 60 in the distant past with a small dome.

 

Assuming you are talking Nauticam, the optical centre is about 6-7mm behind the 140 dome port face. You can estimate the EP for the lens (distance from lens mount flange to apparent location of diaphragm when viewed from the front), and having measured the distance from the lens flange to the housing port flange you can see what if any extension you will need. I don't know the Canon details, and I don't know if you need to use an adapter with your dome.

 

With Sony FF, a 25mm adapter and no other extension works well, given a lens flange to port flange distance of 26-27mm. EPs for the above lenses are approx 43 and 48mm respectively. Misalignment with this combo is -3 (too long) for the Sony and +2 (not long enough) for the Zeiss. But bear in mind EPs can move as you focus close.

 

Yours will be shorter I think. Macros / normal FOV lenses are pretty forgiving of inexact alignment.

 

You can also use a 35 with a flat port, but the central area of sharpness will be disappointingly small.

 

I'm running Marelux.  Their port chart says to use the 140mm dome with no extension. 

Find a bricks and mortar camera store and try focusing inside in lowish light. I use AFC with tracking and medium spot. Don't know what Canon has to offer, but a modern lens and body should be fine.

 

Check the lens reviews!

 

With a dome, it's a good focal length for sharks up to about 2m in clear water, or close-ups of larger sharks.

 

If the sharks are blending into the background you may have to focus on an edge before recomposing.

13 hours ago, JayceeB said:

Thank you, Chris.  I'll think more on the 1.4x.  I'm less concerned with the macro working distance than the performance on sharks in low ambient light.  I wonder if the 35mm focus hunts in those conditions.  I also had a thought that maybe I could run my 14-35 in the 140mm dome, but fix it at 35mm.  I'll have to compare the 2 lens dimensions. 

 

Anyone tried this in real life?

The 14-35 might be a better option, the lens achieves 0.38x magnification and the with 200mm MFD you get 80mm working distance.  I found a review by the digital picture and it said measured MFD was 184mm so that gets you to about 64mm working distance which is right on the dome for the 140mm.  So if it is placed correctly it should work as well as any other 35mm lens.

 

I suspect it might work OK behind the dome between maybe 30 and 35mm, especially considering you are likely to have blue water in the corners, so if you trust yourself not to zoom too far having a zoom gear might allow you to capture a shark that is bigger or approaches closer that you might otherwise not get.  The review also mentions 14-35 AF is extremely fast, while reviews of the 35mm f1.8 mention slowish AF and one mentions a bit of hunting.

 

Looking at the Marelux port chart the Canon 8-15 uses the same extension with the 140mm and 230mm domes - so the 14-35mm should also use the same extension for both the 140mm and 230mm domes.  So presumably you would have nothing to buy if you use the 14-35 with the 140mm, if you are already using it with the 230mm.

Yep, real life sharks don't get that close... not like the tiger beach zoo types :-)... I wasn't to Malapasqua, I only saw vids that could get pretty dark... I was to Cocos, Socorro and Galapagos and at times it was dark there too so perhaps I could relate... I use Sony 16-35 F4 with 180mm glass dome on Nauticam and A1 and that offers quite good picture quality, certainly for video and shark photo wide open. APSC mode gets me to 55mm in video.  Or I would go WWL-1B route. But 180mm glass would be preferred because you don't have to clean bubbles after drop... I missed quite a few shots on Galapagos with WWL and next time I would take 180mm dome for sure.  

 

I took a lot of photos at 35mm end in Cocos and Socorro, they just don't come that close over there. Here is an original frame from the best picture I got on Cocos' Alcyon in 2023 (we got lucky and got clear water that day). The detail is 300% loupe...

 

Edited December 31, 2024Dec 31 by RomiK

16 hours ago, RomiK said:

Yep, real life sharks don't get that close... not like the tiger beach zoo types :-).

So true.  I almost always shoot sharks at 35mm, and usually wished I had more zoom.

So I compared the EF 8-15mm fisheye to the RF 14-35mm, and they’re nearly the same length, so I thought I would try out the 14-35mm with the 140mm fisheye dome port.  I set my expectations extremely low, and was hoping it would give acceptable results at the 35mm end.  I tested it out on two dives today, and took mainly 35mm shots, but also tried some 14mm shots as well.  I was actually pleasantly surprised at how well it performed, at least to my eyes, but I’m not very picky on edge sharpness.  I’ve uploaded a few shots to show 35mm and 14mm  in case anyone is interested.

 

35mm first set.

14mm Second Set

null

17 minutes ago, JayceeB said:

So I compared the EF 8-15mm fisheye to the RF 14-35mm, and they’re nearly the same length, so I thought I would try out the 14-35mm with the 140mm fisheye dome port.  I set my expectations extremely low, and was hoping it would give acceptable results at the 35mm end.  I tested it out on two dives today, and took mainly 35mm shots, but also tried some 14mm shots as well.  I was actually pleasantly surprised at how well it performed, at least to my eyes, but I’m not very picky on edge sharpness.  I’ve uploaded a few shots to show 35mm and 14mm  in case anyone is interested.

 

35mm first set.

Based on that test I'd say you have your solution and it doesn't involve buying anything new.  Corners look fine at 35mm, any unsharpness could just be depth of field.  14mm is of course pretty soft in the corners, but it doesn't sound like you'll need it at your destination.

44 minutes ago, Chris Ross said:

1 hour ago, JayceeB said:

 

Based on that test I'd say you have your solution and it doesn't involve buying anything new.  Corners look fine at 35mm, any unsharpness could just be depth of field.

Thanks for the feedback, Chris.  Yes, I think this will work just fine for my needs, where travel weight is a big stress factor.  Also, I don't remember the last time a solution presented itself with zero cost 🙂

Just a food for thought... since we already spend big $$$ for liveaboards and related travel and these come and go. While investment into a good equipment is there to stay... Imagine diving this destination, all the effort and $$$ which lead to it, you get some great shots of sharks at 35mm and then , perhaps at the end of the dive, there is this fish bowl which screams 'take the picture!'... 180mm glass is like $1400 but that money is going to get used for other space limited travels down the road... and there really isn't substitution for an F4 ultra wide and 180mm combo and selected travel parameters ... just a thought...

 

This bowl is with WWL1 at the widest but 14-16mm would get you quite there. Taken at the end of the dive at Wolf with 35bars ... not much time to play with 🙈🙂

On 12/30/2024 at 4:24 PM, Chris Ross said:

Looking at the Marelux port chart the Canon 8-15 uses the same extension with the 140mm and 230mm domes - so the 14-35mm should also use the same extension for both the 140mm and 230mm domes. 

I see what you're saying with the Canon 8-15mm.  Both the 140mm and 230mm domes require a 30mm extension.

 

 

Perhaps a bit different with the 14-35mm?  The 180mm dome requires a 50mm extension, but the 230mm dome requires a 60mm extension.

 

The test shots I have been making were using the 140mm + 30mm extension exactly as setup for the 8-15mm.  I wonder if it would be worthwhile testing the 14-35 + 140mm + 60mm extension, which I have for my 14-35mm + 230mm dome.  I don't have a 50mm extension.

3 hours ago, JayceeB said:

I see what you're saying with the Canon 8-15mm.  Both the 140mm and 230mm domes require a 30mm extension.

 

 

Perhaps a bit different with the 14-35mm?  The 180mm dome requires a 50mm extension, but the 230mm dome requires a 60mm extension.

 

The test shots I have been making were using the 140mm + 30mm extension exactly as setup for the 8-15mm.  I wonder if it would be worthwhile testing the 14-35 + 140mm + 60mm extension, which I have for my 14-35mm + 230mm dome.  I don't have a 50mm extension.

The 180mm dome will use a different extension as it's not a full hemisphere so I would expect it to need a bit less extension as the centre of curvature is further behind the dome.   Both the 140mm and 230mm dome are closer to a full hemisphere and it appears they have the centre of curvature the same distance behind the dome mounting flange. 

 

You would want to use the same extension on the 140mm dome/14-35 as you do with the 230mm dome.  If you did the test shots with 30mm extension the entrance pupil was likely well forward of the optimum point.  I would expect the 14-35 to perform better at 14mm with the right extension.  I thought you had used the 60mm extension for the tests.

 

I'd suggest trying it dry first to check it doesn't vignette, it shouldn't based on the port chart but you might just catch the corner of the shade which could be solved by zooming in a little.  You can check for vignetting dry as it's purely down to geometry, test shots of course should be UW.

10 hours ago, Chris Ross said:

The 180mm dome will use a different extension as it's not a full hemisphere so I would expect it to need a bit less extension as the centre of curvature is further behind the dome.   Both the 140mm and 230mm dome are closer to a full hemisphere and it appears they have the centre of curvature the same distance behind the dome mounting flange. 

 

You would want to use the same extension on the 140mm dome/14-35 as you do with the 230mm dome.  If you did the test shots with 30mm extension the entrance pupil was likely well forward of the optimum point.  I would expect the 14-35 to perform better at 14mm with the right extension.  I thought you had used the 60mm extension for the tests.

 

I'd suggest trying it dry first to check it doesn't vignette, it shouldn't based on the port chart but you might just catch the corner of the shade which could be solved by zooming in a little.  You can check for vignetting dry as it's purely down to geometry, test shots of course should be UW.

Awesome information!  That makes sense now.  My camera is already packed for today with the 30mm extension, but I will try the 60mm tomorrow.  If the 60mm causes slight vignetting at 14mm, no problem zooming in a bit.  The bulk of my shooting will be at the 35mm end anyways with this setup.

I was able to test out the 60mm extension on the 140mm fisheye dome.  The sun shade appears at top and bottom slightly at 14mm.  At 16mm+, the shade does not show in shots. 

 

14mm

 

17mm

I recently got a housing for my R5 and I happen to own the 35mm 1.8 Macro and 140mm dome, so I decided to try it out. I am happy with the performance and will be taking it out again.

 

Here is a gallery with more and higher quality photos https://client.elijahaasand.com/L6MDMcGdbgiPh

Edited February 14Feb 14 by Elijah Aasand

8 hours ago, Elijah Aasand said:

I recently got a housing for my R5 and I happen to own the 35mm 1.8 Macro and 140mm dome, so I decided to try it out. I am happy with the performance and will be taking it out again.

 

Here is a gallery with more and higher quality photos https://client.elijahaasand.com/L6MDMcGdbgiPh

Thank you for posting these.  It's nice to see some samples from less common lens/dome/port combinations.  Glad it worked out for you.  

Does anyone know what extention would be needed for the zen 170mm Dome and the 35mm 1.8. And how would I calculate that in the future? Zen doesn't seem to have an RF port chart.

On 3/13/2025 at 7:58 AM, Elijah Aasand said:

Does anyone know what extention would be needed for the zen 170mm Dome and the 35mm 1.8. And how would I calculate that in the future? Zen doesn't seem to have an RF port chart.

The extension required for the N120 170mm Zen dome is the same as that required for their 230mm dome based upon inspection of their port charts.   Looking at a couple of lenses it seems the Nauticam 230mm dome and the Zen 230mm dome have the same dimensions and and the same recommended extensions.

 

If you look at a few lenses in the EF port chart you'll see that the 140mm dome and the 230mm dome recommend the same extensions.  In this topic people have been using the 35mm lens in question in the 140mm dome with no extension.  Logically then the 170mm dome with no extension should give equivalent performance.

 

You can also do some calculations on placing the dome centre of curvature at the lens entrance pupil.  This involves basic trigonometry once you know where the entrance pupil is.  There's lots of website to show how to find the entrance pupil/nodla point/no parallax point of a lens.  You can also take a split shot in a tub shooting a stick or a board above and below water The stick should be straight through the water surface.  This topic includes this method:  

 

On 3/13/2025 at 6:25 PM, Chris Ross said:

The extension required for the N120 170mm Zen dome is the same as that required for their 230mm dome based upon inspection of their port charts.   Looking at a couple of lenses it seems the Nauticam 230mm dome and the Zen 230mm dome have the same dimensions and and the same recommended extensions.

 

If you look at a few lenses in the EF port chart you'll see that the 140mm dome and the 230mm dome recommend the same extensions.  In this topic people have been using the 35mm lens in question in the 140mm dome with no extension.  Logically then the 170mm dome with no extension should give equivalent performance.

 

You can also do some calculations on placing the dome centre of curvature at the lens entrance pupil.  This involves basic trigonometry once you know where the entrance pupil is.  There's lots of website to show how to find the entrance pupil/nodla point/no parallax point of a lens.  You can also take a split shot in a tub shooting a stick or a board above and below water The stick should be straight through the water surface.  This topic includes this method:  

 

Thanks for the helpful info! I went ahead and got the 170mm dome, so I’ll be getting in the water soon to test it.