It was time to get wet and test the Canon 8 – 15 mm fisheye on the GH5 in the pool so I made my way to Luton Aspire with the help of Rec2Tec Bletchley.
I had the change to try a few things first of all to understand the store coverage of the fisheye frame, this is something I had not tested before but I had built a little model.
This model ignores the corners the red circle are 90 degrees light beams and the amber is the 120 degrees angle. A strobe does not have a sharp fall off when you use diffusers so this model assumes your strobe can keep within 1 Ev loss around 90 degrees and then drop down to – 4 Ev at 120 degrees. I do not want to dig too deep into this topic anyway this is what I expected and this is the frame.
You can see a tiny reflection of the strobes together with a mask falling on the left hand side… In order to test my theory I run this through false colour on my field monitor, at first glance it looks well lit and this is the false colour.
As you can see the strobes drop below 50 at the green colour band and therefore the nominal width of those strobes is probably 100 degrees. In the deep corners you see the drop to 20 % 10% and then 0 %.
Time to take some shots
The lens is absolutely pin sharp across the frame, I was shooting at f/5.6 in the 140 mm glass dome.
Performance remains stunning across the zoom range. I also tried few shots at f/4
There is no reef background but looks pretty good to me.
The pool gives a strong blue cast so the shots are white balanced.
If you want details of the rig and lens mount are in a previous post
Looking at Nauticam port chart the only option for a fisheye zoom is to combine the Panasonic PZ 14-42 with a fisheye add on lens. This is a solution that is not that popular due to low optical quality.
So micro four thirds users have been left with a prime fisheye lens from Panasonic or Olympus…until now!
Looking at Nauticam port chart we can see that there is an option to use the Speedbooster Metabones adapter and with this you convert your MFT camera to a 1.42x crop allowing you to use Canon EF-M lenses for cropped sensor including the Tokina 10-17mm fisheye. This is certainly an option and can be combined with a Kenko 1.4x teleconverter giving you a range of 14.2 to 33.8 mm in full frame equivalent or 7.1 to 16.9 mm in MFT terms fisheye zoom of which the usable range is 8 -16.9 mm after removing vignetting.
A further issue is that the Speedbooster gives you another stop of light limiting the aperture to f/16 while this is generally a bonus for land shooting in low light underwater we want to use all apertures all the way to f/22 for sunbursts even if this means diffraction problems.
Looking at nauticam port chart an extension ring of 30mm is recommended for the speedbooster and now we have extra 5mm in length Wolfgang uses a 35mm extension. however looking at the lens entrance pupil I have concluded that 30mm will be actually better positioned. Nauticam have confirmed there won’t be performance differences. You need to secure the ring on the dome before final assembly.
The rig looks bigger than the 4.33 dome but the size of the GH5 housing is quite proportionate. It will look bigger on a traditional small size non clam style housing.
The disassembly will be made again in 3 steps.
I am not particularly interested in the 1.4x teleconverter version consider that once zoomed in to 15mm the lens is horizontally narrower than a 12mm native lens so there is no requirement for the teleconverter at all.
This table gives you an idea of the working range compared to a rectilinear lens along the horizontal axis as diagonal is not a fair comparison. The lens is very effective at 8-10mm where any rectilinear would do bad then overlaps with an 8-18mm lens. The choice of lens would be dictated by the need to have or not straight lines. The range from 13mm is particularly useful for sharks and fish that do not come that close.
Horizontal Linear Eq
Wolfgang has provided me with some shots that illustrate how versatile is this set up.
As you can see you can even shoot a robust ghost pipefish!
The contrast of the glass dome is great and the optical quality is excellent. On my GH5 body there is uncorrected chromatic aberration that you can remove in one click. Furthermore lens profiles are available to de-fish images and make them rectilinear should you want to do so.
I would like to thank Wolfgang for being available for questions for providing the 3D print and the images that are featured here on this post.
If you can’t print 3D and need an adapter ring I can sell you one for £7 plus shipping contact me for arrangements.
Note: it is possible to use a Metabones Speed Booster Ultra in combination with a Tokina 10-17mm zoom fisheye and a smaller 4.33″ acrylic dome.
UK Cost of the canon option: £3,076
Uk Cost of the Tokina option: £2,111
However if you add the glass dome back
UK Cost of Tokina with glass dome: £2,615
The gap is £461 and if you go for a Vitrox adapter (would not recommend for the speedbooster) the difference on a comparable basis is £176 which for me does not make sense as the Canon optics are far superior.
So I would say either Tokina in acrylic for the cost conscious or Canon in glass for those looking for the ultimate optical quality.
I was checking the technical details of Alex Mustard Underwater Photography Master Class and the majority of wide angle pictures are taken with a fisheye lens. In the section about shooting sharks Alex says that he prefers to shoot sharks with a fisheye otherwise they look ‘skinny’.
If you look online on underwater video forums you frequently see comments on problems with wide angle lenses connected with the use of a rectilinear wide angle lens in a dome.
The two most common complaints are soft corners and distortion.
Soft corners are due to a combination of lens optical issues and dome port optics. In short any lens is to some extent curved and therefore if you shoot a flat surface the image may be sharp in the centre and softer as you move to the corners. Issues with field of curvature are corrected stopping down the lens. The issue with field of curvature happens everywhere not just underwater.
Right now there are four wide angle lens that can be housed for a micro four third camera:
This lens has a nice working range that allows to capture 100 degrees diagonal at widest setting and still has a 35mm equivalent at the tele end. This is a pretty little lens at $699 is the most affordable option that can be put in a housing. You will need a wide angle port and the zoom gear. The whole combination for your Nauticam housing comes at $1,399. This lens can also be combined with a glass dome but this will make the whole combination much more expensive and you may want to think about getting a better lens instead.
This is an outstanding lens especially on land due to the fast f/2.8 aperture. It is expensive at $1,299.99 and very heavy and bulky. The lens does not fit through the N85 port opening and requires a port adapter this gives the extra benefit of a focus know but with such a wide lens is not really useful due to high depth of field. You will need a 180mm glass dome and the zoom gear for the lens to complete the set up ending at a whopping $3159.99.
I have owned this lens and I have to say that at $799 is the right compromise between wide field of view and price. Furthermore once you get the zoom gear you have the option of a cost effective acrylic dome that will give you a very wide set up for $1589.99. There are reports of poor performance with this lens and it is true that is not as sharp in corners but the results are perfectly acceptable if you stop at f/8 in close shots.
This lens is prone to reflections and flare however once you add the N120 port adapter and the 180mm glass dome this will get you to $2819 at that point you may want to consider the Olympus combination instead.
This is my favourite lens is sharp does not suffer from field of curvature issues and has a very useful zoom range 16-35mm in 35mm equivalent. The zoom gear and the 7″ acrylic dome will take you to 1889.99 that is an excellent price point. The lens is not prone to reflection or flare and as the 7″ dome has the same curvature radius than the 180mm dome it will produce very similar results.
The significant size of the acrylic port and the fact it floats make it ideal for split shots and this is the lens that gives me the best results.
This lens can also take port adapter that allows you to use the 180mm glass dome. This adds up to $2919.99 if you experience bad reflections and shoot frequently in the sun it may be worth it but I have not had any issue so far with this lens probably because of its nano coating.
I have found the 7mm focal length too problematic for dome ports and the amount of perspective distortion excessive generally it would be preferred to shoot at 9mm and narrower however this maybe insufficient for wreck interiors if you want a rectilinear look.
One of the regular complaints of video shooters especially in wrecks or caves is that the edges look horrible and distorted and that there is an issue with the corners pulling. This is in fact not an issue but a problem with perspective as you shoot very wide angle. The following test shots will illustrate that the issue happens on land and has nothing to do with dome ports.
As we can see the football looks like an oval and the chair is pulled. This is due to a perspective issue and is not a lens problem. When you shoot underwater video the objects on the edges of the frame change shape creating this pull effect that most people dislike.
At 9mm the amount of perspective distortion is reduced and this is the reason why 18mm on 35mm equivalent is one of the favourite focal length for rectilinear video and the maximum angle that should be used in small spaces to avoid the pulling edges.
One of the reason why a lens like the Nauticam WWL-1 is preferred for video is because the corners look sharp but is that really true?
Not really let’s apply some barrel distortion to simulate the WWL-1 to the image that looked badly distorted.
Now the football looks circular as we have applied -60 barrel distortion, obviously the rest of the image is now bent but this seems not to be of a concern to most people!
It needs much less correction to bring the 9mm shot into shape and for sure between the 8mm and 9mm the 9mm is the dimension that produces the most acceptable results.
It has to be said that in video with 16:9 aspect ratio most of the issue will be cropped away at the edges but the distortion in the middle of the frame will remain. For the same reason the 9mm image will appear practically rectilinear with no issues
I hope this post was useful there are four options for micro four thirds shooters to use rectilinear lenses I have settled for the Panasonic 8-18mm as in most cases it is still possible to control the perspective issue, I found this impossible at 7mm.
Obviously if you shoot in the blue this problem will not be visible however rectilinear lenses are popular with wreck shooters and I think this posts gives an idea of the challenges at play.
Finally I would discourage the use of the 7-8mm focal length range for video to those that want to have a rectilinear look.
From this post I started supporting Bluewater Photo in US for my links because it still provides multi brand and choice and because I learnt a lot from Scott Gietler Underwater photography guide back in the days where there was no internet resource to learn from.
I see many posts on line debating which macro lens is best for your micro four third system.
If I refer to the Nauticam system we have 4 macro lenses:
For the purpose of this article I will skip the Olympus 30mm as the Panasonic lens is known to be sharper and will focus on the other 3 lenses.
DxOMark is a popular tool for comparison as it gives you the results on one page. I have run it for the Oly 60 and the Pana 30 and 45 on the 20 Mpix OMD E-M1 MKII
Surprisingly the much more expensive Leica performs worse than the other cheaper models, this is confirmed on all internet sites running other type of tests.
What we can see is that there is little difference between the Panasonic 30mm and Olympus 60mm when it comes to image quality so whichever lens you choose your subject at the same level of magnification and aperture will have more or less the same detail.
Common Misconception: Shorter focal length give more depth of field
Many people think that using a longer lens is harder because there is less depth of field this is actually incorrect conceptually.
Enter for the Panasonic GH5 the following parameters
Circle of confusion: 0.015 mm
Focal length 30mm
Distance 10.5 cm (minimum distance of the 30mm Macro)
Result Total depth of field 0.3cm
Focal Length 60mm
Distance 21 cm (as it achieves the same magnification)
Result Total depth of field 0.3cm
So depth of field is not a consideration when choosing a macro lens…
Shooting a subject close to the background
In the following 3 shots am taking an image of a widget at f/11 at 29-44-60 mm on a Leica 12-60 (it is just easier it makes no difference to the outcomes)
At the same aperture you can clearly see that there are no difference whatsoever in the detail and actually overall in the picture you don’t notice anything.
Shooting a subject far from the background
For the second shot I have moved the widget away from the wall.
Again there is no difference in the level of detail of the widget however looking at the background we can see that
The 60mm shot reveals one brick and less than one quarter
The 44mm shot reveals one brick and a half
The 29mm shot reveals two bricks
So while the subject is exactly the same as the 60mm lens has a narrower field of view we see much less of the background.
This means that if you are shooting a nudibranch on the sand or something flat on a rock you won’t notice anything however if there is space behind the subject you will capture much more of that resulting in less subject isolation.
Underwater Comparison 30 vs 60 mm
In the first shot the Rhinopia is taken with a 60mm lens
In the second shot the same Rhinopia with the 30mm (in a different place to be fair)
I have marked up with red the areas that with a longer focal length would have been minimised.
Which Lens to choose?
Now that we have clarified that depth of field is not a consideration and as each macro lens will have the same magnification there are only two factors that matter:
Isolation from background
The 60 mm will have a longer working distance and at the same magnification will isolate the subject better from busy backgrounds, the 60 mm is also better for skittish subject because of the longer working distance. I have this lens and I have borrowed the 30mm in couple of occasions but do not have the 30mm yet.
There are however situations where longer working distance is not a benefit, specifically when the visibility is poor and there are suspended particles or the subject is really large.
In the example below I was at one meter from the two frogfish, a 30mm would have been better however the shot came OK.
I believe the Olympus 60mm is a must lens to have. To date I have not felt the need for the Panasonic 30mm that is indeed a very sharp lens because I have always managed to pull out the shots. However for someone diving in murky water and focussing on nudibranches or subject laying flat on the seabed the Panasonic 30mm could be a better choice. I also want to say that using the 14-42mm at 42mm for me is actually a better choice for portraits and with a close up lens works very well with small subject not super macro and therefore as I already own the 14-42mm and various diopter for me the 30mm is not on the shopping list.
The Panasonic 8mm Fisheye lens for micro four third is a clear winner for close focus wide angle however the lack of zoom and the really wide 180º cover mean that there are many subjects that will look tiny in the frame.
The next option in terms of width is the Panasonic 7-14mm wide angle lens however this requires a large dome for optimal performance making the set up expensive.
Is there anything else left if you don’t want to buy a wet lens and you already have the Panasonic PZ 14-42 X Lumix G?
Panasonic produces an add on lens DMW-GFC1 that is declared to provide 10.5mm equivalent and reduce minimum focussing distance to 16 cm all specs can be found here.
This add on lens can be used with the 4.33″ dome for the 8mm fisheye and the 30 extension.
I took a few test shots and the results are pretty good.
This first shot is at f/5 and is very sharp in the centre.
Fisheye Converter f/5
Getting a bit closer and stopping at f/8 the results are pretty good for an adapter that is less than £100 on amazon.
Barrel distortion is contained so this combination may be good for wrecks where the fisheye effect is a bit disturbing.
If you have the Lumix G Vario X PZ 14-42mm you may want to invest in this little accessory before getting the much more expensive 8mm fisheye even if the Nauticam 30 extension is required. Later on the extension can be used with the flat port 35 and the Olympus 60mm for super macro and the 4.33″ dome of course with the 8mm.
I think it is amazing how much can be obtained out of this lens if we consider wet diopters, wet wide angle lenses and this adapter before you need to get a second lens.
This lens could also work for video with the Panasonic GH4 at 4K however zoom is not recommended with it.
The Lumix G X 14-42 Power Zoom lens is designed for video with a silent motor zoom controlled by a slider that is quite effective to use.
The focal range in 4:3 format is 14-42mm which corresponds to 29-87mm in the standard 35mm format (the crop factor is 2.08 36/17.3 and not 2 how commonly thought in the classic 3:2 aspect ratio).
This lens is not exactly a best in class in terms of performance especially considering quite a bit of vignetting at wide end and distortion that anyway gets corrected nicely in camera for most. A detailed review is here http://www.photozone.de/olympus–four-thirds-lens-tests/765_pana14423556hd
You can see that this is lens is quite sharp at 2868 LW/PH to give you an idea the much more expensive Lumix 12-35mm reaches 3110 LW/PH though sharpness drops at corners to around 2100-2200.
Another interesting characteristic is that this lens performs best at f/3.5-f/5.6 which is close to the widest aperture as we will use this lens with the Nauticam flat port 35 this is all good news.
The lens fits very nicely inside the port leaving space for small filters and close up lenses but not really a lot.
The lens does not really move much between 14 and 42 mm and reaches his longest at 14mm.
I have tried using a set of Inon diopters to see the degree of magnification you can get.
This shot is with an Inon UCL-165 +6.06 diopter.
The smallest frame width with this lens is 42mm however in video mode using the ex tele converter option this becomes a much smaller area achieving in fact super macro easily with the added benefit of larger depth of field.
If you are into pixel peeping you can see some chromatic aberration on the edges this is a combination of the lens and the wet diopter.
I also tried stacking an UCL-165 with the UCL-330 this achieves a capture width of 32mm so we are in super macro zone.
Image quality does not get much worse but there are some internal reflections here on the white surface as the Inon lenses are not coated externally.
Finally I wanted to see if the Inon UCL-100 would work and it does achieving super macro without any fringing. If you want to use this lens for pygmy sea horse photography and do not want to get an Olympus 60mm this or the sub see 10 are the close up lenses to get, also the nauticam SMC is in the same range.
Now onto what is really good of this lens port combination and this is the versatility as you can attach the Inon UWL-H100 and get a very wide 18mm flat wide angle that is very sharp indeed as per previous images
Consider that this image is taken at f/3.5 and the ruler is in the corner at ISO 1600 and you can see that sharpness is more than acceptable.
More interesting is that for some reason with this lens you can fully zoom through even down to 42mm without soft corners.
I have no idea how this is possible but it works just fine.
So if you are a video junkie you can cover the whole 100 degrees wide to super macro with this lens the Nauticam 35 Macro Port the Inon UWL-H100 and the UCL-100. For video it gets even cheaper with the UCL-165. You can of course use the flat port to do nice fish portrait in the mid-range of the zoom.
I forgot to mention the zoom gear which is actually pretty expensive because of the complex spring design.
The total cost for the Nauticam 35 with zoom gear is $510 plus of course the lens itself $290 total of $800.
Inon UWL-H100 + LD adapter = $654
Inon UCL-100 = $282
Inon UCL-165 = $205
Wet Lenses Still total = $936
Wet Lenses Video total = $859
Let’s compare to getting an Olympus 9-18mm with 4″ wide angle port and the Olympus 60mm with 30 extension ring total price $2129.
Price gap for stills $393 but you now also have a mid range lens for portraits, personally I don’t really like the Olympus 9-18 behind that port comparing side by side images taken with the 14-42 PZ and Inon lens I am not sure the Olympus is any better and definitely needs diopters due to mushy corners. For macro the 60mm Olympus lens has the advantage of increased working distance but is a very specific lens that you would only use for really small stuff.
For what concerns video you would probably look at the Panasonic 7-14 and forget the Olympus 60mm the combination is worth $1800 which is a difference of $636. Again the issue with rectilinear lenses and dome ports is there and the 7-14 does not take diopters.
So if we were to use the lenses on land no doubt you would need additional glass but in water wet lenses can be quite cost effective especially if you use a micro four third camera for video.
Peter Rowlands uses a Panasonic GX7 with Inon UWL-H100 and dome successfully and I am joining that club now.
Stay tuned for more tests next to come will be the Panasonic Fisheye 8mm with the 4.33″ dome which is another essential buy for the micro four third cameras underwater, obviously for pictures and not video.