Lens advice for Canon R5 for dolphins please :)

Hi everyone,

I was hoping some of you would be kind enough to offer me some advice, because after weeks of reading up on underwater photography then I am still struggling to decide what to purchase for my purpose. The purpose is a specific one – I am snorkelling with seals and dolphins, and I wish to collect identification images of individual animals for research purposes (so I am interested in stills, rather than video). Until now, I have used only a GoPro as my venture into underwater photography is a new one, but I am an experienced DSLR user topside.

I was initially just looking for housing for my Canon 5DIII, but as it’s a decade old and housing is specific to one model, then I have decided at the same time to upgrade to the Canon R5 and buy housing specific to that in the hope that it will all be good for a few years. So far, so good.

The ‘challenge’ is in deciding on a lens. The mammals I am photographing come close, to within a metre or two of me. I’m looking for a fast lens, to use specifically for this context. I will be photographing in ambient light and not using strobes, and I don’t want a setup that is too cumbersome. Initially I was looking at the Sigma 15mm fisheye, but after reading about compatibility issues with the R5 then I don’t think I can risk it – the Sigma website implies that it might have to be used on manual with the R5 which would make life more difficult with fast-swimming mammals? I’ve struggled to find information on the Tokina 10-17mm compatibility with the R5 too. So, the default option currently seems to be the Canon 8-15 mm fisheye, though it’s more expensive than what I really wanted to spend and I have a few other hesitations about it. I was just going to get a simple housing and a dome port.

I’d be grateful for any thoughts/recommendations – have I missed any obvious alternatives? I’m not experienced with underwater work, and am just looking for something simple, effective and cost-efficient for this one specific purpose. Thank you so much.

Hi Stenella

My experience of photographing fast-moving dolphin pods was in the Red Sea. Two pieces attached as examples.

Unless you can get really close - which from what I found was more luck than anything else - lead me to think something in the fisheye range is too wide. So not 15/16mm, 8-15 type lenses. Even the Tokina 10-17 I'd have my doubts especially on a full frame (FF) sensor camera like the R5 (see below).

What worked for me with a FF sensor was a 16-35mm lens. Like you, no strobes. But this IS a big lens setup which is quite complicated to house on FF. It needs a big dome (230mm) to get sharp corners (more important given the speed dolphins move, I'd suggest) and needs to be stopped down to at least f11 unless you use the Sea & Sea correction lens. In addition it needs  something like a 90mm extension ring to get the correct distance between housing and port glass. So quite bulky. And expensive.

The Tokina 10-17 might work with the addition of a TC1.4 giving you approx 14-25mm on a cropped frame sensor (APS-C). But it is pretty horrible on a full frame sensor with or without a TC.

Simple? Hmmmm. Effective, yep. Cost-efficient? What is in underwater photography!?

The Tokina 10-17 is a DX/APS-C lens so while you may be able to get it work on some cameras, the image quality on a full frame camera will not be fantastic, an APS-C crop would probably be fine - but there's still the compatibility problem.  The Canon 8-15 is of course a fine lens but as you said expensive.

I don't know if you have purchased the R5 as yet, but the normal recommendation is to work backwards to the camera body from your application and also if you have a camera already it may not be the best thing to put in a housing.   For example an Olympus em-1 MkIII with the native 8mm fisheye would do a fine job for that sort of work and the housings, ports and lenses are significantly cheaper.  Alternatively you could look at what bodies you could use with the Tokina lens - one of the Canon APS-C DSLRs or the Nikon D500.  I assume you are on the surface so there should be plenty of light?

If you add up the costs An R5, 8-16 and the Nauticam housing comes to $US9788, while the EM-1 mkIII with 8mm fisheye would be $US5233.  In Isotta it is cheaper at $US7888 /$US4490, still a substantial difference in total cost.  I've used US prices as the info is easy to find, but the difference should be similar in your market.  The domes for fisheye are an addition and would be similar costs for both.  If you go rectilinear as Tim suggests, then the difference swings more in favour of small formats as they use smaller domes. 

If you can reliably get within 2m  a fisheye might be enough.  I looked through my fisheye just now and a 2m long door was a nice size in frame at 1m away - but subjects get much smaller in frame very quickly with a fisheye.  Keep in mind the 8-15 is not really a zoom on full frame it's either a circular fisheye or a 15mm diagonal fisheye.

2 hours ago, TimG said:

Unless you can get really close - which from what I found was more luck than anything else - lead me to think something in the fisheye range is too wide. So not 15/16mm, 8-15 type lenses. Even the Tokina 10-17 I'd have my doubts especially on a full frame (FF) sensor camera like the R5 (see below).

Thanks for your reply Tim  Nice pics of the spinners.

So, I am indeed able to get close. I don’t move much myself, but the animals I work with can be very interactive and approach me and often swim around at close proximity for quite a long time. That’s why I was thinking the 15mm fisheye, but in my inexperience then I do keep worrying that you are right and I might end up needing more zoom. But if a 1.7 m animal is within 2 metres of you (and sometimes within arm’s reach) then what would your thoughts be on a 15mm fisheye in that scenario?

1 hour ago, ChrisRoss said:

I don't know if you have purchased the R5 as yet, but the normal recommendation is to work backwards to the camera body from your application and also if you have a camera already it may not be the best thing to put in a housing.   For example an Olympus em-1 MkIII with the native 8mm fisheye would do a fine job for that sort of work and the housings, ports and lenses are significantly cheaper.  Alternatively you could look at what bodies you could use with the Tokina lens - one of the Canon APS-C DSLRs or the Nikon D500.  I assume you are on the surface so there should be plenty of light?

If you can reliably get within 2m  a fisheye might be enough.  I looked through my fisheye just now and a 2m long door was a nice size in frame at 1m away - but subjects get much smaller in frame very quickly with a fisheye.  Keep in mind the 8-15 is not really a zoom on full frame it's either a circular fisheye or a 15mm diagonal fisheye.

Thanks Chris

No, I didn’t yet purchase the R5. But I was thinking of that camera mostly because I could use it also for the other things I do, including aurora/night photography and landscapes and topside marine mammal work – i.e. it would be a solid multi-tasker. The lens and the housing I could buy specifically for underwater, but I kind of need the body to function a bit more broadly as my 5DIII has done for all these years? Yes, I am snorkelling within 2 m of the surface, so there is light (though its often overcast).

Thanks for the door measurement info, that’s useful to know.

I did see that Canon will soon release a 16mm f2.8 RF lens, but I was worried that might not be wide enough…I’m torn between thinking a 15mm fisheye might be too wide, and anything rectilinear and narrower might not be wide enough!

1 hour ago, Stenella said:

I did see that Canon will soon release a 16mm f2.8 RF lens, but I was worried that might not be wide enough…I’m torn between thinking a 15mm fisheye might be too wide, and anything rectilinear and narrower might not be wide enough!

1 hour ago, Stenella said:

But if a 1.7 m animal is within 2 metres of you (and sometimes within arm’s reach) then what would your thoughts be on a 15mm fisheye in that scenario?

Hey again Stenella

Yeah, dilemmas, dilemas eh? Welcome to the underwater photography world! 

A couple of thoughts: a fisheye lens is by its nature distorting. I'm not sure what a dolphin would look like within arm's reach through a fisheye. I suspect slightly weird! I use a fisheye almost all the time for WA work. If the diver is about, say, 2-3m away and the main focus of the subject is, say a Gorgonian, with the diver acting as the "human element" then the fisheye is great.

You'll see lot of super pics of seals close-up using a fisheye showing prominently the whiskers, cute nose etc. I can imagine you could get some pretty cool "Cute Flipper" pics like that. Could get a bit boring though.

The other thought: you know better than I how fast these things move and therefore what sort of balance in time you might expect between being close-up (fisheye distance) and them scooting away, across, towards you etc.(rectilinear distance).

So then it's back to the dilemma: fisheye or rectilinear. I suspect if you are going to do what you need to do, you need both! But that is probably a counsel of perfection - not to mention a bank balance challenge!

The cheapest option is without doubt the fisheye one. If you are determined to go FF (not, I'd suggest the best choice) you could get a Sigma 15mm, an 8" dome and try it. If it doesn't work, you could then always switch to the rectilinear. Problem then is, of course, that the 8" dome is now not good enough and you need 9". And don't be fooled into thinking an extra 1" won't make much difference: it's night and day in terms of size, cost, portability and weight. So maybe you start out with a fisheye and the 9" dome - adding a 16-35 or some such if you find it necessary.

My suggestion would be to go with an APS-C sensor sized camera and the Tokina 10-17. With that you could get away with a 4" dome. And if that's too wide, add a 1.4TC, a short extension ring (so an extra $250) and you're good to go. You can even use the 4" dome.

Dilemmas.....

Hi Stenella, 

Welcome to Wetpixel. 

I have an R5 topside and it is a fantastic camera, but I'm not sure its going to be best for what you require. 

As  a starter, here's some dolphins from Sha'ab El Erg in Egypt from a 1dx and sigma 15mm to give you an idea of the distortion - admittedly these were shot with strobes at about 15m depth. The dolphins were pretty much on top of me. 

I think you may be better  off with either a R5 with something like  a 16-35mm - the traditional requirement for sharp corners isn't really relevant here as it's likely to be water in the corners, but bare in mind that for other types of work, then yes, you will run into issues with that setup. 

That said, I'd maybe consider going with  an APS-C camera here and either the Tokina 10-17 or one of the 8-15mm fisheyes from whichever brand  you use. You could also  maybe pair that  with a mini  dome for a smaller setup in the water that will be fine  for everything apart from 'split' shots and is easier to manoeuvre through the water.

Out of interest,  whereabouts in the UK are you? If  you're close to Manchester you can maybe take a look at my setup - a Nikon D500 with the above fisheye, and compare it to an old 1dx housing 'I have gathering dust with a larger dome to see how that feels in your hands

Mike

15 hours ago, Stenella said:

Thanks Chris

No, I didn’t yet purchase the R5. But I was thinking of that camera mostly because I could use it also for the other things I do, including aurora/night photography and landscapes and topside marine mammal work – i.e. it would be a solid multi-tasker. The lens and the housing I could buy specifically for underwater, but I kind of need the body to function a bit more broadly as my 5DIII has done for all these years? Yes, I am snorkelling within 2 m of the surface, so there is light (though its often overcast).

Thanks for the door measurement info, that’s useful to know.

I did see that Canon will soon release a 16mm f2.8 RF lens, but I was worried that might not be wide enough…I’m torn between thinking a 15mm fisheye might be too wide, and anything rectilinear and narrower might not be wide enough!

Here's a comparison for you taken from pretty much the same spot you can see how quickly things get small at these focal lengths.  You can now compare sizes of the same object.  You can see the fisheye stretches out a lot more in the corners but the door is not hugely bigger in the frame with the rectilinear lens.  First is 7mm rectilinear - 14mm full frame equivalent and second is 8mm fisheye - equivalent to the 15mm end of the 8-15.  You can also see from the door in the BG how quickly things get smaller in frame.  The door edge closest is about 800-900mm away and the hinges of the BG door about 2.2m away.

To my mind the 7-14 option seems a touch better if the dolphins are not always on top of you.  But a full frame 14mm zoom setup is going to be pricey and bulky.  A complete AOI EM-5III housing with the panasonic 7-14 and 8"dome adds up to $3800 at backscatter this would be ready to go - all you may want to add is a tray so you can use it two handed and it includes a vacuum system for leak checking.  You could easily spend this much just for the housing for an R5.  The downside is it is really setup to use the rear LCD not the viewfinder as far as I can see.

Hi Stenella,

A lot of good advice here...

I have good experience with dolphins in ambient light with Canon 8-15mm fisheye, but with Oly EM1II. One should emphazise that your dolphin photography is for scientific pupose to identify individuals, while ours is "artistic", just to get pleasing pictures. This may well demand different lenses. While most like WA for "artistic" purpose, maybe a regular range zoom lens is better just to take photos of the animals for identifying them and other metrics. These photos will be much less pleasing, since they are made from greater distance, have less contrast and one cannot see the "big scenery", but they mayserve better the scientific purpose. Just an idea, only you can decide what serves your needs better...

Generally, when making photos of fast moving animals using ambient light, you will work with a fixed shutter speed (e.g. 1/400s to avoid motion blurr of the fast moving animals) and aperture is set automatically to get the right exposure. With the small MFT sensor I have, I do not dare to use "Auto ISO" to get better exposure, since too much noise is added at high ISO (I just increase ISO a little to a fix value of 400). With a FF camera "Auto ISO" can be used readily for this type of photography, this is clearly an advantage. You also will want a lens/port combination that allows making photos at wider open apertures to get the maximum of ambient light. Such a combination for R5 is the WACP1. When using Sony A7x (or A1) you could use WWL1 and save money. I do not see the fisheye distortion as a problem - you can easily "defish" the image in LR and perform then your scientific measurements. It is even possible in LR to make a lensprofile for a WACP or WWL1/lens combination by your own and using this profile you get perfect defishing of the image without any distortion...

Wolfgang

To avoid the issue of big domes and port extensions for rectilinear on full-frame you might consider a crop sensor camera with a kit lens and a WWL-C water contact optic. This provides a compact, light rig, 130 degree corner to corner view, rectilinear  but with some barrel distortion. The corners are better than a dome on full frame. You can see a comparison of angle of view for Tokina 10-17, Sigma 8-16 and WWL-C on my phuketpools facebook page https://www.facebook.com/phuketpools/ On the Nikon Z50 the Tokina 10-17 doesn't autofocus. There's also a picture of the Nauticam Z50 housing and WWL-C on phuketpools earlier on.

On 10/2/2021 at 6:02 PM, TimG said:

So then it's back to the dilemma: fisheye or rectilinear. I suspect if you are going to do what you need to do, you need both! But that is probably a counsel of perfection - not to mention a bank balance challenge!

The cheapest option is without doubt the fisheye one. If you are determined to go FF (not, I'd suggest the best choice) you could get a Sigma 15mm, an 8" dome and try it. If it doesn't work, you could then always switch to the rectilinear. Problem then is, of course, that the 8" dome is now not good enough and you need 9". And don't be fooled into thinking an extra 1" won't make much difference: it's night and day in terms of size, cost, portability and weight. So maybe you start out with a fisheye and the 9" dome - adding a 16-35 or some such if you find it necessary.

Thanks Tim. As you have surmised, my bank balance is not endless and I can't really afford to get two separate setups as wonderful as that would be. I am anxious about making the wrong choices and then finding I have to buy everything again from scratch because the housings or domes don't fit whatever replacement I discover I need! Also, where I work is pretty remote and its not as easy as just 'pop into a camera shop' or 'next day delivery'. I'd be waiting a couple of months for stuff to be shipped most likely (not a disaster as the dolphins aren't going anywhere, but it's all a bit of a pain).  I think the main thing I have learnt in this thread is that I simply don't know enough to make an informed decision, because everyone is recommending crop sensor when I had assumed that full frame was the only thing to be certain of. Haha. So, it's back to another several weeks of reading for me I think!

On 10/2/2021 at 8:17 PM, pooley said:

I have an R5 topside and it is a fantastic camera, but I'm not sure its going to be best for what you require.

Out of interest,  whereabouts in the UK are you? If  you're close to Manchester you can maybe take a look at my setup - a Nikon D500 with the above fisheye, and compare it to an old 1dx housing 'I have gathering dust with a larger dome to see how that feels in your hands

Mike

Thanks very much Mike Unfortunately I'm down in the south-west and quite a long way from Manchester or I might have taken you up on this! Interesting that you're not recommending the R5. My amateur-level research on the interweb informed me that the R5 was going to be a super-duper underwater camera but no-oneon this thread has supported that!  Further illustrating my hopeless lack of knowledge on this topic...

On 10/3/2021 at 8:12 AM, ChrisRoss said:

Here's a comparison for you taken from pretty much the same spot you can see how quickly things get small at these focal lengths.  You can now compare sizes of the same object.  You can see the fisheye stretches out a lot more in the corners but the door is not hugely bigger in the frame with the rectilinear lens.  First is 7mm rectilinear - 14mm full frame equivalent and second is 8mm fisheye - equivalent to the 15mm end of the 8-15.  You can also see from the door in the BG how quickly things get smaller in frame.  The door edge closest is about 800-900mm away and the hinges of the BG door about 2.2m away.

To my mind the 7-14 option seems a touch better if the dolphins are not always on top of you.  But a full frame 14mm zoom setup is going to be pricey and bulky.  A complete AOI EM-5III housing with the

and 8"dome adds up to $3800 at backscatter this would be ready to go - all you may want to add is a tray so you can use it two handed and it includes a vacuum system for leak checking.  You could easily spend this much just for the housing for an R5.  The downside is it is really setup to use the rear LCD not the viewfinder as far as I can see.

Thanks so much Chris for taking the time to post these comparisons. It occurs to me that I should produce a lifesize cardboard dolphin and do some experiments of my own with my various lenses, GoPros etc to get more of a feel for how things might look in practice  I'm going to have a look into the possible Olympus setup you mention in your two posts - thanks for suggesting this. I must admit that, perhaps ignorantly, the one thing that I was certain that I needed for my underwater venture was a full frame sensor size because I am working with fast-moving animals in not great light (I'm very shallow, but it is often overcast, and sometimes turbid) and I need to optimise light and shutter speeds so as not to get blurry dolphins. Topside, that's why I ultimately opted for full frame to maximise light and good shutter speeds for my cetacean work, over the additional magnification of the crop sensor camera. I regularly work with 7D II and Canon 5D III/IV for my cetacean ID work above the water, and the image quality from the 5Ds almost always surpasses what I get with the 7D even when I have to crop the 5D images to zoom in on dorsal fins. Maybe its different underwater, this is what I am uncertain about now after reading all this replies recommending crop sensor or even the four-thirds system. Basically, I'm more confused now than I was when I started, haha. 

On 10/3/2021 at 10:18 AM, Architeuthis said:

One should emphazise that your dolphin photography is for scientific pupose to identify individuals, while ours is "artistic", just to get pleasing pictures. This may well demand different lenses. While most like WA for "artistic" purpose, maybe a regular range zoom lens is better just to take photos of the animals for identifying them and other metrics. 

Thank you for your reply Wolfgang, and for recognising the specific context of what I aim to do and concerns re. sensor size etc. It's really helpful to know that I'm not entirely on the wrong path with the FF reasoning.

On 10/3/2021 at 10:18 AM, Architeuthis said:

Such a combination for R5 is the WACP1. When using Sony A7x (or A1) you could use WWL1 and save money. I do not see the fisheye distortion as a problem - you can easily "defish" the image in LR and perform then your scientific measurements. 

Now we get into technical stuff that I know almost nothing about  I am aware of WACP1, WWL, etc only from having seen them in this forum and some initial googling. I almost fell off my chair when I saw the price tag for a WACP1, lol. I guess I was hoping my entire setup would be around this price, not just one part of it (however awesome that part might be, and I understand it probably is). I will go and read more...

On 10/3/2021 at 12:00 PM, PeteAtkinson said:

To avoid the issue of big domes and port extensions for rectilinear on full-frame you might consider a crop sensor camera with a kit lens and a WWL-C water contact optic. This provides a compact, light rig, 130 degree corner to corner view, rectilinear  but with some barrel distortion. The corners are better than a dome on full frame. You can see a comparison of angle of view for Tokina 10-17, Sigma 8-16 and WWL-C on my phuketpools facebook page https://www.facebook.com/phuketpools/ On the Nikon Z50 the Tokina 10-17 doesn't autofocus. There's also a picture of the Nauticam Z50 housing and WWL-C on phuketpools earlier on.

Thanks very much for your thoughts and for the helpful photo links. One thing I definitely do need is some fast autofocus, but I am not a Nikon user anyway (for no reason except that I went the Canon route initially and then got trapped there my by lenses!). 

OVERALL CONCLUSION FOR NOW: I'm clearly not knowledgeable enough to make a good decision on this and your feedback was a little mixed (which I expected as opinions always vary, but I'm now less certain than when I started about even the choice of body!), so I'm going to keep reading some more. Thanks everyone for your input, its really appreciated even though I wish you would have all recommended the same thing and it would be simple and easy (haha) 

Simple.  Easy.  Underwater. Photography. There’s 4 words you never read in one sentence. 

Good luck with it, Stenella. You know where to come if you need more conflicting advice. 

5 hours ago, Stenella said:

Thanks so much Chris for taking the time to post these comparisons. It occurs to me that I should produce a lifesize cardboard dolphin and do some experiments of my own with my various lenses, GoPros etc to get more of a feel for how things might look in practice  I'm going to have a look into the possible Olympus setup you mention in your two posts - thanks for suggesting this. I must admit that, perhaps ignorantly, the one thing that I was certain that I needed for my underwater venture was a full frame sensor size because I am working with fast-moving animals in not great light (I'm very shallow, but it is often overcast, and sometimes turbid) and I need to optimise light and shutter speeds so as not to get blurry dolphins. Topside, that's why I ultimately opted for full frame to maximise light and good shutter speeds for my cetacean work, over the additional magnification of the crop sensor camera. I regularly work with 7D II and Canon 5D III/IV for my cetacean ID work above the water, and the image quality from the 5Ds almost always surpasses what I get with the 7D even when I have to crop the 5D images to zoom in on dorsal fins. Maybe its different underwater, this is what I am uncertain about now after reading all this replies recommending crop sensor or even the four-thirds system. Basically, I'm more confused now than I was when I started, haha.  

 

I think if budget was no barrier going an R5 and WACP would be a nice option as in the low light is indeed better in so far as you can still stop down as required by dome port optics and bump up the ISO without bringing up the noise.   But Housing full frame gear tends to be expensive.  The other option to look at is a WWL and that reduces the range of cameras you can consider as suitable lenses to use with it is much more limited.

I would think you could use ISO800 with the EM-5 mkIII and probably get away with f5.6  in an 8"dome, the corners would not great but there should only be water there.  I don't have a good feel for what sort of light levels you are dealing with and what sort of details you are trying to capture for ID, but I have the impression that even at ISO 1600 you would have good detail  but the noise would be quite noticable but unless you need fine detail would be good enough for ID purposes??

The other option when light is in short supply is of course to open up the aperture and with dome ports this a problem.  You could look into a WWL setup for the same housing I mentioned before, it actually adds up cheaper at $USD3072  and has a similar horizontal field of view to the 7-14 lens but zooms to around the field of maybe a  20mm lens.  It's a f3.5-5.6 lens so fairly fast lens at the wide focal lengths and I believe shooting it at f4 would be fine.

I have a Canon R5, which I'm currently using with the 16-35 F4 EF lens via control ring adapter, and anxiously awaiting availability of the new Canon 14-35 RF F4 lens. It's small, light, and looks to perform rather well... and would give you a great zoom between 14 and 35... Which seems to really cover the bases for what you need. 

Also, if you're looking to save money, you could go the route I'm going and get the Ikelite 200DL housing for the R5... It'll end up costing you about $2500 for the housing, extension, 8" dome port, and zoom gear... That's a HECK of a lot less expensive than other manufacturers, and IMO, every bit as serviceable. 

I'm a huge fan of the R5... the autofocus and eye tracking smokes anything else out there, the 4K 120fps and 8K video recording are incredible, and the dynamic range and internal stabilization give you a huge level of "forgiveness" for low light situations. Just my 2 cents!

On 10/5/2021 at 12:44 AM, ChrisRoss said:

I think if budget was no barrier going an R5 and WACP would be a nice option as in the low light is indeed better in so far as you can still stop down as required by dome port optics and bump up the ISO without bringing up the noise.   But Housing full frame gear tends to be expensive.  The other option to look at is a WWL and that reduces the range of cameras you can consider as suitable lenses to use with it is much more limited.

I would think you could use ISO800 with the EM-5 mkIII and probably get away with f5.6  in an 8"dome, the corners would not great but there should only be water there.  I don't have a good feel for what sort of light levels you are dealing with and what sort of details you are trying to capture for ID, but I have the impression that even at ISO 1600 you would have good detail  but the noise would be quite noticable but unless you need fine detail would be good enough for ID purposes??

The other option when light is in short supply is of course to open up the aperture and with dome ports this a problem.  You could look into a WWL setup for the same housing I mentioned before, it actually adds up cheaper at $USD3072  and has a similar horizontal field of view to the 7-14 lens but zooms to around the field of maybe a  20mm lens.  It's a f3.5-5.6 lens so fairly fast lens at the wide focal lengths and I believe shooting it at f4 would be fine.

Thanks Chris, I appreciate it. Still pondering...!

12 hours ago, DynamicDivers said:

I have a Canon R5, which I'm currently using with the 16-35 F4 EF lens via control ring adapter, and anxiously awaiting availability of the new Canon 14-35 RF F4 lens. It's small, light, and looks to perform rather well... and would give you a great zoom between 14 and 35... Which seems to really cover the bases for what you need. 

Also, if you're looking to save money, you could go the route I'm going and get the Ikelite 200DL housing for the R5... It'll end up costing you about $2500 for the housing, extension, 8" dome port, and zoom gear... That's a HECK of a lot less expensive than other manufacturers, and IMO, every bit as serviceable. 

I'm a huge fan of the R5... the autofocus and eye tracking smokes anything else out there, the 4K 120fps and 8K video recording are incredible, and the dynamic range and internal stabilization give you a huge level of "forgiveness" for low light situations. Just my 2 cents!

Thank you very much, nice to hear something positive about the R5! Yes, I had indeed been looking bat the Ikelite 200 DL housing for it already, as a (relatively!) cost effective option. This thread has caused me to hesitate a bit about going ahead though. The 14-35 RF lens is available here, and wasn't one I had considered previously - thanks for this suggestion, that could work for me! :-) 

5 hours ago, Stenella said:

Thanks Chris, I appreciate it. Still pondering...!

 

Thank you very much, nice to hear something positive about the R5! Yes, I had indeed been looking bat the Ikelite 200 DL housing for it already, as a (relatively!) cost effective option. This thread has caused me to hesitate a bit about going ahead though. The 14-35 RF lens is available here, and wasn't one I had considered previously - thanks for this suggestion, that could work for me! :-) 

It is still relatively expensive - the lens in $US costs as much as the housing and the biggest domeport offered by ikelite (8") is a little on the small side for a 14mm lens, though to be fair for your dolphin project it may be acceptable as the corners will be water.  For the price of the housing plus 14-35 only you could purchase the full system I suggested with WWL which is a more flexible option with 3x zoom and better optics - in general the WWL  with kit lens will out perform any rectilinear wide in a dome port.   The only question mark will be low light performance of the smaller sensor. 

Don't get me wrong about the R5, it is a fine option and I am only suggesting you look elsewhere due to budget concerns.

On the question of exposures, the 14-35 will need to be shot at f11-16 while the WWL could be shot at f4.  So if you could shoot f4 and iso800 on the m43 with WWL then at f11 you would be shooting ISO6400 on a full frame lens all else being equal.  The smaller apertures that you can shoot with m43 lenses/sensors even things up a little. 

Im using actually a Canon R5 in Nauticam Housing with a 15-35mm lens... the picture i have attached was taken with a 5DIV and a 16-35mm and a 8,5" Acryl Dome. 

If you have any questions about this, feel free.

Super picture, Michael!