Canon FF lens lens lenses..

[Orestis Papadakis]

Hi all,

 

I'm pretty new around, with no experience in UW photography and photography in general (my background/gear info can be found here: https://waterpixels.net/forums/topic/890-hello-from-greece/#comment-3772).

 

I am looking for FF lenses that I can use with my Canon EOS R6 Mark II for both UW and general photography (UW being the priority at this point).

The two lenses I will use for sure are the RF 24-105mm f/4L IS USM, which I already have as a kit lens, and the RF 100mm f/2.8L IS USM, which I will use mainly for macro.

 

The dilemmas for wide-angle:

EF 8-15mm f/4L USM fisheye +EF to RF mount

I keep reading and being told that this lens is an absolute must for wide-angle and close-focus wide-angle UW photography.

The point is that I don't intend to use the spherical aspect of this lens, so I'll have to use it all the time at 14-15mm, while I'm not sure I even like the fisheye effect of the 14-15mm (the latter may be due to my complete lack of experience with photographic perspective in general). I am also not sure how well this lens could catch up with the improvised autofocus of the R6mii, compared to the newer RF lenses. Lastly, I don't know if the lack of IS, could also be a drawback.

 

RF 10-20mm f/4L IS STM

In my perception, this could be the best alternative to the ef 8-15mm, as I can use its full focal length for full-frame images without the spherical/fisheye effects.

My doubts have to do with a) its insane price (can't find it used anywhere in the EU yet), b) I don't know how good this lens is for close-focus wide-angle, and c) the complete lack of UW reviews. 

From a quick search, I saw that the member @CaolIla owns this lens, so I would be really grateful for a short review.

 

RF 14-35mm f/4L IS USM

I would only consider this lens as an alternative, but cannot see its use among the others on this list.

 

RF 15-35mm f/2.8L IS USM

This lens would have been my first choice for UW and general use, as the f/2.8 could really come in handy for more artistic/all-around photography, while its 15mm focal length is still very wide.

My doubts have to do with its ability to shoot wide-angle and close-focus wide-angle UW, compared to the ef8-15mm or the rf10-20mm, as its minimum focusing distance (28cm) is also quite long.

 

minimum focus distances:

EF 8-15mm f/4L: 15cm

RF 10-20mm f/4L: 17cm

RF 14-35mm F/4L: 20cm

RF 15-30mm f/2.8L: 28cm

 

At the moment, in terms of usability and price for both UW and general use, I think the most realistic solution is the combination of an EF 8-15mm f/4 and an RF15-35mm f/2.8 (I could find both in less price than the rf10-20mm alone), but again, if I could limit my choices to a single lens capable for UW wide-angle and close-focus-wide angle, that would be ideal.

 

What is your advice/thoughts?

Thanks in advance, and sorry for the messy/ long text...

 

Orestis

 

 

 

 

 

 

[TimG]

Hi Orestis

 

Forgive me if this is, using a British expression, teaching granny to suck eggs, but if you are new to u/w photog maybe the following might help with some context:

 

One of the weird things about u/w photography is that you have to rethink how you view lenses. Wide-angle on a FF sensor can be tricky.

 

Unless you plan to use the slightly more esoteric Nauticam lens additions (a more standard zoom plus one of the WWLs and the like), for wide-angle you tend to use the ultra-wide stuff. So a fisheye is often the norm for u/w. I can well appreciate you're not keen on the fisheye look but underwater you don't really see it as there are few-to-no straight lines to highlight the effect. You just get ultrawide.

 

I'm attaching a couple of shots all of which were shot with a 15mm fisheye so you can see. The diver(s) was/were probably 2m away from me.

 

The other part is that you don't really need the fast lenses either, eg, the f1.8s, f2s, etc. But you do need WIDE! So, in my view, I wouldn't bother to try and house your 24-105mm. 24mm is too narrow underwater and 105 not much use unless genuinely macro.

 

The other "challenge" with wide-angle on a FF sensor is finding a dome that doesn't leave the corners of the image horribly soft. For example a 16-35mm lens on a FF sensor really needs a 230mm dome and, even then, edges can be a bit dodgy. By contrast, a fisheye lens has no problem. Strange world eh?!?

 

I'm not a Canon user so can't comment on the 10-20mm zoom underwater but the range makes very good sense. Others will no doubt chip-in about how it works.

 

Totally agree on the 8mm end of the 8-15mm. That is one specialist view! It's good for the occasional shot but not many. However the 15mm (it's a fisheye) is very good for u/w wide-angle shots.

 

I'm sure others here will weigh in on the standard zoom plus the WWLs . They are a relatively new option and allow the use, as I say, of a more standard zoom lens but adding a chunky, pricey piece of glass in front. They do seem very versatile and would be worth you considering. You might need to do a calculation on the price compared to the classic big domeport route. There is also the issue then of moving heavy, chunky gear if you have to fly to dive. 

 

Macro: yep, the 100mm sounds good.

 

I hope this helps!

 

 

 

 

 

 

 

[Orestis Papadakis]

55 minutes ago, TimG said:

Forgive me if this is, using a British expression, teaching granny to suck eggs, but if you are new to u/w photog maybe the following might help with some context:

 

 

 

 

As I am not a granny but I do like eggs, and considering that 2 months ago I literally had no idea what the aperture, shutter speed, or iso stood for in photography (not to mention I had never used a "real" camera), any input from experienced people is invaluable! 

For the moment I'm just trying to catch up by studying, reading reviews, watching videos and shooting in manual all day...

 

 

1 hour ago, TimG said:

Unless you plan to use the slightly more esoteric Nauticam lens additions (a more standard zoom plus one of the WWLs and the like), for wide-angle you tend to use the ultra-wide stuff. So a fisheye is often the norm for u/w. I can well appreciate you're not keen on the fisheye look but underwater you don't really see it as there are few-to-no straight lines to highlight the effect. You just get ultrawide.

 

I'm sure others here will weigh in on the standard zoom plus the WWLs . They are a relatively new option and allow the use, as I say, of a more standard zoom lens but adding a chunky, pricey piece of glass in front. They do seem very versatile and would be worth you considering. You might need to do a calculation on the price compared to the classic big domeport route. There is also the issue then of moving heavy, chunky gear if you have to fly to dive. 

 

Unfortunately, as I have spent/invested my savings on the camera and complete u/w gear, upgrading to the more advanced Nauticam / WWL, although definitely a plan, for the moment is not an option. For now, I will have to stick and learn with the Ikelite DL200 housing and relevant domes/extensions, while my very first trials will be with the 24-105mm +4diopter....

 

 

1 hour ago, TimG said:

One of the weird things about u/w photography is that you have to rethink how you view lenses. Wide-angle on a FF sensor can be tricky.

 

I'm attaching a couple of shots all of which were shot with a 15mm fisheye so you can see. The diver(s) was/were probably 2m away from me.

 

The other part is that you don't really need the fast lenses either, eg, the f1.8s, f2s, etc. But you do need WIDE! So, in my view, I wouldn't bother to try and house your 24-105mm. 24mm is to narrow underwater and 105 not much use unless genuinely macro.

 

The other "challenge" with wide-angle on a FF sensor is finding a dome that doesn't leave the corners of the image horribly soft. For example a 16-35mm lens on a FF sensor really needs a 230mm dome and, even then, edges can be a bit dodgy. By contrast, a fisheye lens has no problem. Strange world eh?!?

 

I'm not a Canon user so can't comment on the 10-20mm zoom underwater but the range makes very good sense. Others will no doubt chip-in about how it works.

 

Totally agree on the 8mm end of the 8-15mm. That is one specialist view! It's good for teh occasional shot but not many. However the 15mm (its a fisheye) is very good for u/w wide-angle shots.

 

 

Finally, I'm starting to love the 8-15mm! 😂

What I'm still struggling to understand, is why I can't use the rf15-35mm fixed at 15mm and have similar results with the ef8-15mm, also at 15mm, as I assume they will both provide a similar field of view. Also, does the minimum focusing distance of the 15-35mm make such a huge difference for a close-focus wide-angle shot?

The edge sharpness comparison you mention between the 16-35mm and the fisheye, does indeed make our world a lot stranger! In any case, I already have the 230mm and 160mm domes, and a flatport, waiting for their lenses.

Maybe the ef8-15mm for u/w plus the versatile rf15-35mm f2.8 for general use is indeed the way to start (+the 100mm), unless I get some extraordinary feedback on the rf10-20mm.

 

 

Thank you very much Tim!

This is a completely new world for me and every piece of advice is very helpful at this stage!

 

 

 

[TimG]

Hey Orestis

 

Good that I'm not teaching you to suck eggs even though you love them!

 

No, sadly the 15mm in the 8-15mm is not the same as the 15mm in the 15-35mm. The 15mm in the 8-15 will be, I imagine (as I said I'm not a Canon guy) a fisheye construction; whereas the 15mm in the 15-35 will be rectilinear - so not the curved effect of the fisheye but based on creating a straight, i.e. not curved, image.

 

I don't know about the minimum focussing distances on those lenses but, generally, a fisheye can focus much close than a rectilinear.

 

Usually for CFWA shots I'd use a fisheye plus a 1.4 teleconvertor (nothing is simple, right?) as this allows you to get VERY close to the subject but still have a wide field of view behind the subject - hence locating the subject against its habitat.

 

If you already have the 230 dome then you are good to go with the 15-35 but will need some form of extension ring between the dome and the housing to provide the space the lens needs. Have a look on the Ikelite website for this. 

 

What you suggest as a start point sounds good to me. 

[Orestis Papadakis]

12 minutes ago, TimG said:

Hey Orestis

 

Good that I'm not teaching you to suck eggs even though you love them!

 

No, sadly the 15mm in the 8-15mm is not the same as the 15mm in the 15-35mm. The 15mm in the 8-15 will be, I imagine (as I said I'm not a Canon guy) a fisheye construction; whereas the 15mm in the 15-35 will be rectilinear - so not the curved effect of the fisheye but based on creating a straight, i.e. not curved, image.

 

I don't know about the minimum focussing distances on those lenses but, generally, a fisheye can focus much close than a rectilinear.

 

Usually for CFWA shots I'd use a fisheye plus a 1.4 teleconvertor (nothing is simple, right?) as this allows you to get VERY close to the subject but still have a wide field of view behind the subject - hence locating the subject against its habitat.

 

If you already have the 230 dome then you are good to go with the 15-35 but will need some form of extension ring between the dome and the housing to provide the space the lens needs. Have a look on the Ikelite website for this. 

 

What you suggest as a start point sounds good to me. 

 

Thank you Tim! All eggs are welcome! 

 

Yes, in fact, the focusing distances are 15cm for the 8-15 and 28cm for the 15-35.

When I understand what a teleconverter really does, I hope to be able to use one instead of the simple ef to rf converter for the fisheye.

As for the port extensions, I already have the ones needed for the 24-105 and 100mm and will get all the necessary ones for the other lenses to come.

 

I understand the difference between the curved image of the fisheye and the rectilinear of the 15-35 (or the 10-20mm), but what I still can't understand is why the curved fisheye effect alone is really needed when the field of view could be the same (or even wider if we consider the 10-20mm).

In the following video, my confusion might be more understandable as it compares the 10-20mm, 11-24mm and 15-35mm with the 8-15mm fisheye (when the latter is supposedly always used at 14 or 15mm), but I suppose that u/w it's a completely different perspective, especially with CFWA.

https://www.youtube.com/watch?v=l09paPVaFxM

 

I hope my questions and lack of knowledge are not too frustrating.

 

 

 

[CaolIla]

5 hours ago, Orestis Papadakis said:

RF 10-20mm f/4L IS STM

In my perception, this could be the best alternative to the ef 8-15mm, as I can use its full focal length for full-frame images without the spherical/fisheye effects.

My doubts have to do with a) its insane price (can't find it used anywhere in the EU yet), b) I don't know how good this lens is for close-focus wide-angle, and c) the complete lack of UW reviews. 

From a quick search, I saw that the member @CaolIla owns this lens, so I would be really grateful for a short review.

Yes

 

 

For the moment I'm didn't travel with it. I only dive in lac in the north east of France.
I had some trouble with my dome. I explain the extension is to short. I mount a new one with 10 mm more . But not dive with it for the moment. 

 

Here some pictures I haven't more for the moment, the condition wasn't good 

 

Gravière du Fort 2023/12/31 | Flickr

Gravière du 2024/01/28 | Flickr

 

End of June I will have more pictures, from north Sulawesi

But I'm REALLY happy with this lens. OK it's expensive but I love the results.

The only problem I had was the lost of sharpness on the side... but it's not a lens problem.

 

[CaolIla]

5 hours ago, Orestis Papadakis said:

RF 14-35mm f/4L IS USM

I would only consider this lens as an alternative, but cannot see its use among the others on this list.

It the lense I used for wide angle pictures since 2 years... I was happy and will probably take it with me for the next travel. 

The RF10-20mm    have maximum 20 mm 😉 the 14-35 its 35mm... some times depending of the dive type... why not.

 

 

[CaolIla]

5 hours ago, Orestis Papadakis said:

and the RF 100mm f/2.8L IS USM, which I will use mainly for macro.

 

 

It's an incredible lens... to take small things but also to make some portrait of fishes.

 

or Turtle like this

 

 

Edited February 15 by CaolIla

[ColdDarkDiver]

I have an R5 and an R6ii and a variety of the lenses discussed.  Of all of them, the go to is easily the 8-15mm fisheye.  I tape it in 15mm mode and it focuses just great on any of the bodies.  I was slow to pick it up since I didn't think I wanted the fisheye look.  I was wrong.. I did. I dive with it all the time now and with a nice and small 140mm dome.  I love it.

 

I do miss the IS but since there is in body, I still get great shots and you can shoot it wide open aperature since it is a fisheye.

 

I also have and use the 14-35 and have used it with both a 180 and 230mm dome.  Its superb - sharp, fast, wonderful color and contrast.  The 7-8 stops of stabilization is also really nice.  On both domes it is a bit soft in the corners, but not to the point where I don't dive it all the time.  I especially use this lens when shooting video (it is my go to video lens).  This lens is also a joy to use above water.  I try to shoot it at around 18mm when I care about corners, but I also don't not shoot it at 14mm.  

 

I did not get the 15-35 F/2.8 since it is more expensive, larger, and there is not a 2.8 use scenario for underwater photography.  I still sometimes almost impulse buy it - but I have not done so.  This one also doesn't go to 14mm so while the 14-35 is softer in the corners at 14... it isn't really an option with the 15-35.  Above water, I also like a smaller size even though I have read that the 15-35 is a better lens, I can't imagine it getting me any images or better than I have gotten using the 14-35.

 

The other lens that I like is the 24mm macro. It is really small, "cheap", very sharp and you can use it with a 180mm dome with zero extensions so it is a nice and small package (for a FF underwater rig).  Great backup video rig or stills.  I was hesitant to dive with this until I realized all of my days shooting on P&S and even Nikonos slide were at 24mm or longer.  I will shoot this one pretty open as well and the images are nice.

 

I have not shot the 10-20mm.  Looks sweet. I haven't seen a review underwater for it though. I would think you would always need at least a 230mm dome if not the 250.  I'd get the 8-15 first without giving it a second thought.  I also have the 11-24mm and haven't even bothered to take it underwater since I always just end up using the 8-15 (stills) 14-35 (video) 24mm Macro (feeling like a simple dive and want to be able to get really close to stuff cause the vis stinks), or 100mm macro (macro dive but clear enough water to have some working distance).

 

Happy diving!  

 

[TimG]

42 minutes ago, Orestis Papadakis said:

I understand the difference between the curved image of the fisheye and the rectilinear of the 15-35 (or the 10-20mm), but what I still can't understand is why the curved fisheye effect alone is really needed when the field of view could be the same (or even wider if we consider the 10-20mm).

 

No problems with the questions, Oretsis. That's the whole point of this forum 😆

 

I'm afraid an explanation of the optics involved is way beyond me. I just know what I use and the effect it will have. If you want to shoot largish critters who won't come close, then the 15-35 is the way to go. But because of the natural turbidity caused by water, getting as close as possible - and reducing the amount of water between the camera and the subject - is key. A fisheye of 15mm will let you do this better than a 15mm rectilinear - as you read from the minimum focussing distances you found.  So you get close, but you still have the really wide view.

 

The other point about using an FE is the size of dome you can use. Mine is a mere 100mm  - tiny compared to a 230. This allows you to tuck strobes in tight to light a CFWA scene where, often, you are only cms from the subject. You just cannot do that with a 230 dome.

[Orestis Papadakis]

10 minutes ago, CaolIla said:

Yes

 

 

For the moment I'm didn't travel with it. I only dive in lac in the north east of France.
I had some trouble with my dome. I explain the extension is to short. I mount a new one with 10 mm more . But not dive with it for the moment. 

 

Here some pictures I haven't more for the moment, the condition wasn't good 

 

Gravière du Fort 2023/12/31 | Flickr

Gravière du 2024/01/28 | Flickr

 

End of June I will have more pictures, from north Sulawesi

But I'm REALLY happy with this lens. OK it's expensive but I love the results.

The only problem I had was the lost of sharpness on the side... but it's not a lens problem.

 

 

6 minutes ago, CaolIla said:

It the lense I used for wide angle pictures since 2 years... I was happy and will probably take it with me for the next travel. 

The RF10-20mm    have maximum 20 mm 😉 the 14-35 its 35mm... some times depending of the dive type... why not.

 

 

 

Thank you very much Caollla!

With the images you shared, I can now clearly visualise the difference u/w between the curved fisheye and the rectilinear perspectives, in almost the same field/width of view. For some very strange (to me) reason, the curves of a fisheye look more natural underwater, which doesn't seem to be the case on land. That was very helpful.

I would really appreciate a review when you use the 10-20mm some more!

 

Cheers

[CaolIla]

2 minutes ago, Orestis Papadakis said:

I would really appreciate a review when you use the 10-20mm some more!

I'll dive again probably in 1 week... but in the lac as in the 2 albums i posted.
 

  

an other..

Raw without any change... visibility 😞


I love the rectilinear lenses.. underwater and over

[CaolIla]

I like this lines not curved 😉

have anybody picture with a FE from such things to see the differences underwater ?

i'm curious 

[Orestis Papadakis]

25 minutes ago, ColdDarkDiver said:

I have an R5 and an R6ii and a variety of the lenses discussed.  Of all of them, the go to is easily the 8-15mm fisheye.  I tape it in 15mm mode and it focuses just great on any of the bodies.  I was slow to pick it up since I didn't think I wanted the fisheye look.  I was wrong.. I did. I dive with it all the time now and with a nice and small 140mm dome.  I love it.

 

I do miss the IS but since there is in body, I still get great shots and you can shoot it wide open aperature since it is a fisheye.

 

I also have and use the 14-35 and have used it with both a 180 and 230mm dome.  Its superb - sharp, fast, wonderful color and contrast.  The 7-8 stops of stabilization is also really nice.  On both domes it is a bit soft in the corners, but not to the point where I don't dive it all the time.  I especially use this lens when shooting video (it is my go to video lens).  This lens is also a joy to use above water.  I try to shoot it at around 18mm when I care about corners, but I also don't not shoot it at 14mm.  

 

I did not get the 15-35 F/2.8 since it is more expensive, larger, and there is not a 2.8 use scenario for underwater photography.  I still sometimes almost impulse buy it - but I have not done so.  This one also doesn't go to 14mm so while the 14-35 is softer in the corners at 14... it isn't really an option with the 15-35.  Above water, I also like a smaller size even though I have read that the 15-35 is a better lens, I can't imagine it getting me any images or better than I have gotten using the 14-35.

 

The other lens that I like is the 24mm macro. It is really small, "cheap", very sharp and you can use it with a 180mm dome with zero extensions so it is a nice and small package (for a FF underwater rig).  Great backup video rig or stills.  I was hesitant to dive with this until I realized all of my days shooting on P&S and even Nikonos slide were at 24mm or longer.  I will shoot this one pretty open as well and the images are nice.

 

I have not shot the 10-20mm.  Looks sweet. I haven't seen a review underwater for it though. I would think you would always need at least a 230mm dome if not the 250.  I'd get the 8-15 first without giving it a second thought.  I also have the 11-24mm and haven't even bothered to take it underwater since I always just end up using the 8-15 (stills) 14-35 (video) 24mm Macro (feeling like a simple dive and want to be able to get really close to stuff cause the vis stinks), or 100mm macro (macro dive but clear enough water to have some working distance).

 

Happy diving!  

 

 

 

24 minutes ago, TimG said:

 

No problems with the questions, Oretsis. That's the whole point of this forum 😆

 

I'm afraid an explanation of the optics involved is way beyond me. I just know what I use and the effect it will have. If you want to shoot largish critters who won't come close, then the 15-35 is the way to go. But because of the natural turbidity caused by water, getting as close as possible - and reducing the amount of water between the camera and the subject - is key. A fisheye of 15mm will let you do this better than a 15mm rectilinear - as you read from the minimum focussing distances you found.  So you get close, but you still have the really wide view.

 

The other point about using an FE is the size of dome you can use. Mine is a mere 100mm  - tiny compared to a 230. This allows you to tuck strobes in tight to light a CFWA scene where, often, you are only cms from the subject. You just cannot do that with a 230 dome.

 

 

Finally I think the combination of an 8-15mm for u/w and a 15-35mm f/2.8 is indeed what I'm looking for at the moment, without rejecting the 14-35 f/4 (it's just that the f/2.8 might be more versatile for all-around purposes). 

I have also considered the rf24mm f/1.8 macro for land/all-around use, and I'm glad you mentioned it, because I hadn't even thought of it for u/w.

The photos Caollla shared are what I really was not able to visualize for a rectilinear wide angle underwater. This was the eye-opener I was looking for.

 

Everything is well explained and spot on! Happy to be here! 🙂

Thank you all so much for your time and valuable information!

 

[CaolIla]

A very important point (for me) is to have a perfectly balanced buoyancy.

 

 

Important for wide-angle but much more for macro shooting.
If you have a heavy lens, you'll need more float stuff to compensate the weight

 

[Orestis Papadakis]

1 minute ago, CaolIla said:

A very important point (for me) is to have a perfectly balanced buoyancy.

 

 

Important for wide-angle but much more for macro shooting.
If you have a heavy lens, you'll need more float stuff to compensate the weight

 

 

Thanks Callloa! I already have some trim weights for the large domes, as well as "foam" floats for the strobe arms, which I will test thoroughly. I do understand the importance of neutral buoyancy and right balance, as it is also essential in many aspects of my work.

 

 

[Chris Ross]

2 hours ago, Orestis Papadakis said:

I understand the difference between the curved image of the fisheye and the rectilinear of the 15-35 (or the 10-20mm), but what I still can't understand is why the curved fisheye effect alone is really needed when the field of view could be the same (or even wider if we consider the 10-20mm).

In the following video, my confusion might be more understandable as it compares the 10-20mm, 11-24mm and 15-35mm with the 8-15mm fisheye (when the latter is supposedly always used at 14 or 15mm), but I suppose that u/w it's a completely different perspective, especially with CFWA.

https://www.youtube.com/watch?v=l09paPVaFxM

 

I hope my questions and lack of knowledge are not too frustrating.

 

 

 

The point to remember is the field of view between rectilinear and fisheye is not the same the rendering is quite different between them as the fisheye uses barrel distortion to achieve a 180° diagonal field, something not possible in rectilinear lenses.    Also the diagonal field is a bit misleading for comparisons as well as fisheyes stretch more in the corner, if you want to compare coverage then using the horizontal field works better.  See this table below which lists field s of various focal lengths.

 

Full frame	horizontal	vertical	diagonal
15mm Fisheye	143	92	178
10mm Rect	122	100	130
14mm rect	104	81	114
16mm Rect	97	74	107
20mm Rect	84	62	94
24mm Rect	74	53	84

 

You can see the 10mm goes close and in fact the vertical field is larger than the fisheye,   However it needs a big dome port to provide good corners.

 

Another thing to remember is just because a lens performs well on land it doesn't always translate to good UW performance.  In particular a lens needs to focus very close to work well in a dome.  Your 24-105 lens for example has a minimum focus distance of 450mm but is measured to focus at 332mm at the wide end, so while it will work in the domes specified it won't let you get in close.  UW photography is all about getting in close to minimise the amount of water which degrades the image between you and the subject.  Which brings up another point in that just because you own a lens (or a camera for that matter) doesn't mean it's the best option to take UW. 

 

A big reason you want close focusing lenses is also because in dome ports you are actually trying to focus on a virtual image underwater, this is located 3 dome radii from the port surface , so quite close.  Some older lenses would not even achieve focus with a dome UW.  This link explains:  https://oceanity.com.au/articles/view/understanding-flat-port-and-dome-port-theory.

 

Another important point with fisheye lenses is their rendering UW, most will focus on the dome if required and because of the barrel distortion the centre portion of the frame is magnified compared to the edges - it looks fatter so is makes the chosen foreground subject stand out against the background.  UW there are very few straight lines unless you are in a wreck or you include the surface in the frame edges you don't notice the barrel distortion as a problem.  They also generally work well in smaller domes.

 

Rectilinear lenses have their places for wreck photos and also some scientific work, but they need usually big domes to work at their best, but this varies with the lens, very close focusing lenses seem to be able to use smaller domes in general.

 

 

[Chris Ross]

3 hours ago, Orestis Papadakis said:

 

 

When I understand what a teleconverter really does, I hope to be able to use one instead of the simple ef to rf converter for the fisheye.

 

 

When using a tele converter with the 8-15 you need to use the TC in addition to the RF-EF converter not instead of.  The EF lenses won't achieve focus without the RF-EF converter which is basically just an extension tube.

 

Also if you are on Canon and don't think you will use the Spherical fisheye option you could consider using the SIgma 15mm fisheye instead, it's cheaper and many people are quite happy with it.

[ChipBPhoto]

Wow - I am impressed at all the amazing knowledge shared in this single discussion!  @Orestis Papadakis all I can say is welcome to the addiction!  And what a fun addiction uw photography is!

 

I am both a long-time Canon photog and now also have a Sony for uw work.  Your R6ii is an amazing body that will perform extremely well both underwater and above.  If I could share a couple points from my days asking the very same questions….

 

First, I too hated the fisheye look.  I do a lot of wreck photography.  With that said, a fisheye, even on a wreck with many straight lines, is actually a powerful tool to highlight your subject or even a particular part of the wreck.  As @TimG said, it just “works” in the underwater world.  On my first Canon I used a fisheye almost exclusively with great success.

 

Now step forward to 2020 when I bought my first full frame uw body….

 

It was then when I was introduced to a new world of Water Contact Lenses.  I had dreams of owning a big 230 dome so I could look like the other talented photogs on the boat and make those same quality images.  Nauticam, however, set an entirely new path of bringing a brand new way for our cameras to see much sharper, and at wider apertures.  They also wanted to make a non-remarkable lens such as a 24mm or 28mm into a wide angle dream with 130 degree field of view!  While not quite a 180 fisheye, 130 degrees was by far better than most out there, AND it would zoom as well.

 

The WACP was born!  It was a hit to all that used it.

 

…It was also quite expensive.  

 

Shortly after, they introduced the WWL series to be an even smaller, cheaper solution with similar results.  Basically, a WACP “lite” that the rest of us could afford.  Oh, and they can literally focus on a subject almost touching the dome!  
 

After learning all this in 2020, I reluctantly purchased a WWL with my 2020 system and it was literally all I could ever want!  I had full zoom in a wide field of view and sharp corners without having go to f/13 or above.  This meant I didn’t need to push my strobe power to the max and I could experiment with more shallow depth of field for more unique, professional looking images.  f/11 and quite often f/8 will yield acceptably sharp frames, even in the corners.  Canon has now introduced the very affordable RF 24-50 which works exceptionally well behind the Nauticam WWL-C.  
 

Remember I said I said almost always used a fisheye pre-2020?  That was before the WWL.  And the discussion of whether you should add a 1.4 teleconverter to the 8-15 now completely goes away.  With the WWL you have a wide lens AND a zoom for additional reach, all in the same port.  No need to decide before you dive; this one solution will do it all!

 

So does it completely replace my Canon 8-15?  Mostly, yes.  I still have the 8-15 with a 140 dome for ultra wide, clear water dives.  It has, however, become a specialty tool for specific circumstances with the WWL being my primary, or go-to lens.
 

Since you are just starting out, I highly encourage you to do some research into a WWL-C before you get too far down the path with large domes, extensions, etc.  

 

The entire lens, port, and WWL-C will most likely be much less cost than a larger dome, all with terrific sharpness.  Oh, and did I mention it is substantially smaller than a 230 dome?  Huge bonus if you travel or just don’t want to drag around big gear.  
 

As a side not, I own the RF 14-35 for landscape work.  It is terrific lens, but the RF 24-50 with the WWL will do the same underwater much easier and sharper. 
 

Is there a downside to the WWL series?  The only one is you cannot do split images (over-unders) with it.  For me, that was not an issue as I would rarely do them.  Size, cost, and sharpness were my drivers in my decision and the WWL hit them all.
 

Hope this helps without throwing too much confusion in the party. 😁 

 

 

Edited February 15 by ChipBPhoto

[Chris Ross]

1 hour ago, ChipBPhoto said:

 

Remember I said I said almost always used a fisheye pre-2020?  That was before the WWL.  And the discussion of whether you should add a 1.4 teleconverter to the 8-15 now completely goes away.  With the WWL you have a wide lens AND a zoom for additional reach, all in the same port.  No need to decide before you dive; this one solution will do it all!

 

So does it completely replace my Canon 8-15?  Mostly, yes.  I still have the 8-15 with a 140 dome for ultra wide, clear water dives.  It has, however, become a specialty tool for specific circumstances with the WWL being my primary, or go-to lens.
 

Since you are just starting out, I highly encourage you to do some research into a WWL-C before you get too far down the path with large domes, extensions, etc.  

 

The entire lens, port, and WWL-C will most likely be much less cost than a larger dome, all with terrific sharpness.  Oh, and did I mention it is substantially smaller than a 230 dome?  Huge bonus if you travel or just don’t want to drag around big gear.  
 

 

 

 

I think this highlights another saying:  "horses for courses".  Chip, you mention wrecks are a favourite and that fisheye gets less use now except for certain subjects.   The phrase certainly subjects highlights why I think a different approach will be very helpful.

 

Start with your subject and work backwards.  If you are doing wrecks a lot a rectilinear may make sense or a WWL, if you are doing CFWA on tropical reefs or sometimes even in temperate waters a fisheye comes into its own by bringing the subject forward in the frame and giving it prominence while the background is sent backwards and this creates a unique look.   Fish portraits depending on their size will have a different solution.  Scientific photography may demand low distortion for some applications, the list goes on. 

 

So subject will define the lenses you want, then work out which port of if you want a wet optic.  Next work out what camera you want to use and based upon lens/port selection choose a housing that will support the ports and/or water contact optics you want to use.  All of these choices have various pros and cons to weigh up.

 

Before jumping in and buying lots of optics think hard about what you want to shoot with them, then ask what is the best solution for that.  Next ask how much flexibility do you want, this may push you in a different direction.

[ChipBPhoto]

Agreed that subject or interest could be useful in helping select the best lens/port option.  The wet optics allow a wide variety of uses from a single lens, such as the RF 24-50 for your R6.  I find CFWA and reefscapes are nicely captured with the WWL (and WACP) series due to their ability to focus so closely to the subject while retaining a wide zoom range.  As an example, I’ve been able to fill the frame with a small flamingo tongue thanks to that remarkable close-focus, and then capture a huge school of snapper above the reef line a few minutes later using the wide end.
 

In editing, I find great success in *not* using the lens profiles in LR.  (With the Sony 28-60)  It allows the slight barrel distortion in wide scenes to have a slight almost fisheye feel to bring out the subject vs. flattening it.

 

Everyone needs to find their own way and what meets their personal needs best.  Wet optics are relatively new, and a new way of approaching frequent questions we all face.  Regardless of the tools used, the enjoyment of the search and personal happiness with the results are what counts most.

 

Best of luck and have fun in the decision process! 
 

Edited February 16 by ChipBPhoto

[ColdDarkDiver]

2 hours ago, ChipBPhoto said:

 

As a side not, I own the RF 14-35 for landscape work.  It is terrific lens, but the RF 24-50 with the WWL will do the same underwater much easier and sharper. 

 

 

Is it inappropriate to dislike a post because it may cost me some more money?  I have been intrigued by the 24-50 +WWL.  Thanks for the insight! 

 

Also "I find great success in *not* using the lens profiles in LR. "  - Agreed! I have found in general avoiding lens corrections (below water) is the solution to many of my initial complaints about images. 

[ChipBPhoto]

5 minutes ago, ColdDarkDiver said:

Is it inappropriate to dislike a post because it may cost me some more money?  I have been intrigued by the 24-50 +WWL.  Thanks for the insight! 

Yeah, I’ve been told I’m a bad influence.
Glad I could help…drain your account.  😂

 

[CaolIla]

7 hours ago, Chris Ross said:

However it needs a big dome port to provide good corners.

That's a reason why I'll buy a "new" 9" dome in the near futur i'm a little bit unhappy with the quality in the corner

[TimG]

Chris’ makes a point I think important. If you have specific images in mind you need to decide what you need to use to create that.
 

From my experience this works much better than having a setup that can shoot whatever turns up.  It’s not only about gear in that case but also mind set. You “see” the u/w world differently if you know a site has creature x or wreck y and that’s what you want to shoot. 
 

But that can be difficult when you start out as typically you don’t really know what you want to do and just want to shoot everything you see!

 

it becomes more of a consideration though when you’ve been shooting for a while and the initial excitement of photographing underwater turns into a more reflective phase.