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.
When people think about creating lighting technique for underwater photography a few things come to mind and usually it is about tools. Snoots for example have become very popular and help the underwater photographer to increase separation of the subject from the background. I have seen some people jumping in the water with a black slate to create an artificial black background, clearly is much easier to do that for macro as everything is at end and typically the subjects are not fast moving or the diver is not fast moving.
Then of course there is strobe positioning, classic, inward, crossed, rabbit ears, backlighting etcetera here goes a long list of options.
At the end however some pictures just seem to “pop” more than others, and this usually has to do with the colours and the contrast and with the blue.
It is not a coincidence that the term Mustard Blue is what has made some shots from Alex Mustard re-known and if you read his underwater photography masterclass there is a whole section ‘The sea is blue’ where Dr. Mustard goes on about the importance of exposure and background blue.
His suggestions are to:
Dial in an underexposure (for the water) around -2/3 to -1 1/3 Ev
Using warm strobes
It is worth stressing out that the primary reason why the camera gets fooled by the conditions underwater is because colours gets absorbed and blue lights gets scattered instead creating that milky glare at times when the water has lots of suspended particles.
If shoot an auto mode with exposure compensation at zero your pictures will for most part come out washed out and lacking contrast underwater and this is one the primary reasons photographer like Dr Mustard do not follow the expose to the right rules.
Underexposure for the water is obtained by keeping the aperture and ISO constant as they are aligned to the strobes and changing the shutter speed accordingly. Obviously if you are shooting video your shutter speed is most likely fixed so you need to find alternative ways to get your blue as you want it but generally you would still underexpose probably not as much.
With regards to warm strobes this is a fairly subtle point linked to the camera auto white balance mechanism.
Most flash strobes have colour temperatures between 5500 and 6500 K and therefore are not at all particularly warm.
Inon has developed warming diffusers for their Z240 range and I believe also for the most recent Z330 range. They are available in 4600K and 4900K temperature. I definitely recommend the 4600K version over the 4900K as it has a stronger effect.
So how does a warm strobe work in order to get a richer blue?
When we shoot with strobes the camera is set to auto white balance, and will average for most the subject we hit with our strobes to calculate the average colour temperature and tint.
The camera auto white balance operates between 2500K and 7500K typically so a warm strobe is likely to set the colour to 4600K instead of the typical 5500K the ‘extra’ 900K do not really do anything to the subject that will anyway we white balance but give an extra kick to the blue background. Underwater colour temperature is usually higher than 9000K and easily reaches 14000K (purple tone in the water) at depth. So the warm strobes are particularly effective in shallower and clearer water as they push the blue to a darker tint like in this example taken around 12 meters.
You can see how deep is the blue other example taken on the Barge at less than 10 meters.
So what happens if you don’t have a warm strobe or if there aren’t warm diffusers for the strobe you have, or maybe you don’t want to spend the money for them?
Amazon comes to the rescue
If your strobe is around 5250 with diffusers (like Sea and Sea YS-D2 or Inon S2000/Z240/D200) get a 1/8 CTO
Be careful not to exceed with this technique or subject will turn too warm.
An alternative and perhaps counterintuitive approach is to use cooling filters.
In this case the strobe light will become colder to emulate the water colour and the camera will need to be set to custom white balance.
In almost all cameras except Olympus that reach 14000K colour temperatures are limited to 10000K however they can be further enhanced to reach 11000K if you have an adjustment panel like the Panasonic or Sony cameras. Pushing the adjustment to the A gives extra 1K. This technique with a bare lens has however a limitation as when the custom white balance caps the colours go completely off.
In order to see what can the colour temperature setting do we can compare a normal grey card shot with one where the colour temp is 11000K and magenta is pushed to the max.
In order to cool down the strobes you need a cyan filter, the custom white balance can correct up to 2 stops Cyan but no more. You can trim a sheet of Rosco 4360 to fit into your diffuser as below. This takes around 1 stop Ev off the strobe.
It important to stress that the predominant colour in blue and blue water is cyan not blue and this is what gives the washed out scattering. We want to keep the deep blues and get rid of light blue and green which ultimately is cyan the colour of water.
So the strobe will emulate the water and the camera custom white balance will set the colour restoring what was lost and giving us a full correct spectrum. This however only works until the water colour temperature gets to 11000K and this is not as deep as you may think it could be a low as 9-10 meters. A cyan 60 filter is approximately 9500K. You can see the colour in the image below.
In this technique the strobe is not used to give colour but to eliminate shadows the custom white balance is going to give a deep colour that penetrates the whole frame so any subject in the distance will be colourful as well.
The benefit of this technique is that you may use wider apertures and even slower shutter speeds like in this 1/60 example here.
You can clearly see the orange colours of the anthias far behind in the frame.
The ultimate stretch of this technique is to combine a filter like the magic filter this can be used with both a Cyan 2 stops and also a Cyan 3 stops in deeper water. This technique is taxing on exposure as your strobes are half power and your exposure has 1 2/3 stops less however this is easily recovered as you tend to shoot at slower shutter speeds of 1/30 to 1/60 instead of 1/125 to 1/200 because the filter will give you the deeper blues.
The magic filter adds around 3000K to you camera custom white balance ability reaching the 14000K where the water starts turning purple blue. To that regards due to the amount of red I do not recommend going to deep with the magic and keep it to a max of 13 meters as recommended on their website.
The magic filter is almost a perfect match for the Cyan 60 filter if you overlap them over the lens you get almost a neutral grey card the temperature is only 150K off while the tint is around 5 notches toward green in Lightroom.
This cave shot I believe gives an idea and is taken with filter on lens and strobes.
I have also tried the magic filter with Cyan 90 however there are some side effect to consider. Firstly you get Cyan cast on the image at shallower depths. Second the magic filter has a tendency to turn purple below a certain depth so I recommend to use the magic with the Cyan 60 as you are certain that the foreground subject and the strobe filter will give you a neutral colour. If you are in deeper water and the temperature is above 10000K this will only result in a deeper blue and a warmer light on the subject that once RAW corrected will look just fine.
In this post I have tried to give you some tips on how to use gels to give deeper blue or richer colours to your wide angle. I would recommend to start with warming diffusers and then move to cyan filters and finally to magic filter and cyan filter in combination.
A final word for video shooters. I am not aware of any add on warming diffusers for video lights and generally I have not seen LED warmer than 5000K therefore unless you shoot at 60p 1/125 it will be very hard to get deep blue at shallow depths without a lens filter.
It is possible to buy a larger card such as the reference that is 7.5″x10″ however this is cumbersome and I found the Studio version to work well with the Panasonic GH5 as it only uses the central part of the frame for white balance.
Going back to our GH5 instruction manual you can also see that the camera white balance is limited to 10,000K which is the colour of blue sky.
Underwater due to light absorption at longer wavelengths red and orange disappear at depth and blue tends to scatter over suspended particles. So the colour temperature of water tends to be higher than 10,000K and also the blue is somewhat washed out by scattering.
This is the reason filters are essential because reduce the amount of blue or to say better cyan and bring the camera into a range where custom white balance works again.
I have already posted a whole range of observations on filters in a previous post so am not repeating here.
With the right filter for the water colour I dive in and with the appropriate white balance card you can get some pretty decent results with custom white balance.
To help the colour accuracy I have experimented with the Leeming Luts and I want to thank Paul Leeming for answering my obscure questions. Obviously you do not have to use the LUTs and you can design them yourself however I found that using the Cinelike D LUT I have a very good starting point for colour correction.
The starting point is a CineLike D profile with saturation, noise reduction and sharpness set to -5 all other settings to default as suggested by Paul, there is no need to lower the contrast as CineLike D is already a flat curve.
*Noise and sharpness have actually nothing to do with grading but are set to -5 as the GH5 applies sharpening and noise reduction even at -5 setting. Sharpening has generally a negative effect all around while noise reduction if required is better performed in the editor.
Looking at imaging resource tests of the GH5 we can appreciate that the camera colours are oversaturated by default.
The GH5 tends to push deep colour and wash out cyan and yellow. This becomes apparent when we look at a white balanced clip uncorrected.
The Leeming Lut helps rebalancing the camera distorted colours and when you apply the camera LUT, provided you have followed the exposure instructions and applied the profile as described, the improvement is immediate.
From here onwards it is possible to perform a better grading and work to improve the footage further.
One other thing that I believe it is interesting is that while generally for ambient light or balanced light shots I do not actually trust the camera exposure and go -1/3 to -2/3 for close up shots exposing to the right greatly helps highlights recovery
In the two frames you can see the difference the LUT brings restoring the correct balance to the head of the turtle.
To be clear the turtle detail has been white balanced in water on the whibal card while using a Keldan Spectrum filter -2, then in fcpx automatic balancing is applied. The LUT brings out a better dynamic range from the same frames.
Obviously you are free to avoid lens filters and LUTs and to some extent it is possible to get similar results however the quality I obtain using automatic settings I believe is quite impressive.
I found myself most times correcting my own wrong exposures or wanting to increase contrast in scene where I had little however this only happens in sever circumstances where white balance and filters are at the limits.
There are many paths to get the right colours for your GH5 underwater videos in my opinion there are four essential ingredients to make your life easier and give your footage a jump start:
Take a custom white balance using a professional grade white balance card
Set the right picture profile and exposure when shooting
(Recommended) Use appropriate filters for the water conditions
Apply the appropriate LUT to eliminate the errors in the GH5 colour rendering in post processing
With the following settings producing a video like this is very simple and all your efforts are in the actual cutting of the clip.
Please note some of the scenes that look off are shot beyond the working conditions of filters and white balance at around 25 meters…
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.
There is no doubt that the Panasonic GH5 is a very capable camera and in given conditions the video performance you can get is truly impressive.
Broadly speaking a video clip needs to be:
Those 4 characteristics are tightly related to:
Today everyone shoots 4K and after all resolution is well supported by almost any camera, broadly is unaffected by other factors and unless the noise is really high sharpness of your frame is not going to be a real issue shooting at 4K.
In normal conditions and not underwater a camera can resolve many colors. However underwater due to the diffraction of light and selective absorption of colours the starting point is very different from land. So generally is not the camera that cannot resolve the colors but the colors that are missing to start with. This post will focus specifically on this aspect. The Panasonic GH5 can resolve 23.8 bits in RAW and therefore technically has less than 8 bits color depth – do not confuse this with the 8 or 10 bit recording setting.
Underwater scenes tend to have limited dynamic range, with the exception of sunbursts or shooting against the light this is going to be an issue only in specific circumstances of very bright scenes with shadows. In all scenes taken with video lights dynamic range is not an issue at all. The GH5 has 13 stops of dynamic range but rarely this is an important consideration.
Noise is an important consideration as when the noise goes up the camera looses the other characteristics, color, dynamic range and resolution will be affected when the camera is outside the sweet spot. Broadly speaking the Panasonic GH5 does not do well once you pass the ISO 1600 setting and I tend to cap the ISO in video at 800 in most cases.
To understand how those variables play we can see how the same set up reacts very differently in scene where there is less light and therefore the camera uses high ISO like this one.
The same camera with exactly the same equipment in brighter water produces this
So the reason for the above is that with less light there are less colours and the clip looks what it is really.
OK moving on to the main subject of this post how do I get the colors right? It is a combination of techniques and the trick is to use the right one in the right conditions.
Generally every site has specific conditions that change depending on weather, time of the day, visibility and other factors. So in broad terms a site will have more or less light and therefore more or less colours. It is therefore impossible to categorically define what to do at a given depth but is more about typical values. With this in mind we have typically 3 scenarios:
Ambient light shots
Artificial light shots
Balanced light shots
Close up Shots
In general close up shots especially of small subject fall within the scenario 2 for which a video light with high color rendering is important as this will define the colours you see. With a lot of power it is possible to extend artificial lighting to larger subjects but eventually you run out of power due to distance or size of the subject.
Wide angle shots and seascapes
True wide angle shots are generally ambient light shots which also means when it gets too dark the colors will be missing and it will look blue not matter the equipment.
In order to make the most of ambient light shots for wide angle it is essential to balance the colours in water even when you use a RAW format on a still image because RAW files are not as RAW as you think and are actually compressed.
Custom White Balance
Using Custom White balance with a grey card it is possible to obtain decent results until the camera hits the maximum color temperature in the case of the Panasonic GH5 this is 9900K. Depending on conditions you may get to 10-12 meters and this still works, in darker water this stops working much sooner.
Color filters push the limit of custom white balance further down. Some add more or less 4 meters others up to 6-8 meters at the expense of an overall loss of light. Filters are useful when there is a lot of light because also help to keep the Panasonic Gh5 in the best aperture range (not smaller than f/11)
Right now there are predominantly 3 filters on the market:
All those filters will improve the performance and color rendering of your footage, under the conditions that the loss of light is not pushing the camera above reasonable ISO values.
In terms of depth range the magic filter and the Keldan Spectrum -2 version can be pushed to 15 meters depth on a bright day in clear water. The URPRO is capable of getting a few meters more down to around 17-18 meters although it does generate an orange cast (as there is no red left) it is still workable.
Typical Max Depth
1 2/3 Ev
Keldan Spectrum -2
2 stop (WWL)
1 2/3 Ev
This image gives an idea of the 3 filters as you can see they are very different one from the other.
Balanced Wide Angle Shots
This is an entirely new technique that has started with the Keldan Ambient light filters. I wrote a whole piece on wetpixel
The principle is to use custom white balance with or without filter to obtain color rendering and then put filters on the video light so that the color of the light emulates the ambient light and therefore it only gives texture not color.
Keldan has developed a whole range of filters for various situation that match their light and therefore are not applicable to any other light.
As I do not own a set of Keldan I have done some tests and found that a gel of Cyan filter 2 or 3 stops makes my divepro G18+ practically ambient light in the conditions I dive into.
The above value are based on my experience use at your own risk especially with different lights.
To give an idea I overlapped the filter to my iPhone lens
This is the shot without any filters
This example shows that the two filters cancel themselves the result is almost daylight with no cast which means in water if you use a video light or a strobe you will not see a red or orange spots on the image.
For those taking pictures the same combination remains true with Inon Z240 and Sea and Sea YS-D2
Example picture here
One thing to take into account is that you need to find a way to hold the gel on the video light or the strobes. The flat surface strobe diffusers make this process easy, finding something you can use with your video lights is not easy and also the gels may melt after continuous use.
It comes a point and a depth where filters stop working, this could be as shallow as 8 meters in green water. As the scene is dark using lights is what is required. There is nothing specific about this technique except making sure you don’t get burned highlights or backscatter. As it happens in photography using long arms (maybe not as long as for stills) is key to get good lighting on your subject.
My Camera Settings
I use CineLike D with saturation, sharpness and noise reduction to -5. I shoot at 24/25p AVCI 400 mbps and follow the 180 rules, it is entirely possible to shoot at 1/100 if you like more crisp look.
Clearly there are people out there that do not like filters and think white balance is best etc but I think a good read on magic filters explains it all.
Diving for images or video can be frustrating at times. I find this less so for macro and super macro where you are resort based and you can hire a guide with super sharp eyes that will help you find the right subjects. For wide angle it is a totally different story. Land based may preclude the best access to certain destinations whilst if you are on a liveaboard with divers there is a conflict of interest. The boat will typically run a fixed itinerary cruise and the result is that you will visit many times so more memorable than others and typically just once. The single dive you do may not be at the right time of the day and the ambient light may not be the best for what you trying to do.
I am self taught and I like to read books and experiment myself however some years ago I was invited by Nauticam to a Red Sea workshop with Alex Mustard.
What I really liked about that workshop was the ability to steer the boat to the right sites, to be able to dive at the right time of the day and also to repeat dives on the best sites and omit the areas that were not promising. For me this had great value on its own.
Of course Dr Alex Mustard tuition was also superb however I have now done this workshop 3 times and I believe that element has become less interesting. I also happened to work in Sharm El Sheikh as resident instructor at the Marriot Hotel so all dive sites were already known to me as a diver at least.
On those workshops I found very useful the fact that you could see the work of others and learn from the group, I also like the fact that there was no competition so everybody was encouraged to share.
Needless to say that after years of diving the same sites I still find the Northern Wreck and reefs of the Red Sea one of the best imaging destination in the world so I thought how do I have the same experience without the workshop part and the related high costs – it costs almost double a standard diving trip to book Alex workshop and they are fully booked almost immediately.
A further issue that has occurred in time is that there are no flights to Sharm El Sheikh from UK and now majority of boats live from Hurghada. This seriously limits the workshop as you have a lot more navigation.
So my ideal requirements for such a trip would be:
Boat to live from Sharm El Sheikh not Hurghada. I rather have indirect flights and burn land time vs consuming cruise time in transfers
Need to be able to have full control of the itinerary
Dive as a photographer with a loose buddy concept
Have a good boat and logistics
Have small number of people in the water – I think 20 is too much so I have set my target to 8 min 12 max
I reconnected with my old network and after looking around I have found a boat and a company that can help with this.
King Snefro is the only liveaboard fleet currently departing from Sharm El Sheikh and the boat of choice is the Snefro Pearl
Cruise Dates: 1-8 August 2020
Price: €1250 per Pax in twin cabin includes:
12 Liter tanks
3 meals, snacks and soft drinks, tea and coffee
Special imaging orientated dive briefing to make the most of the sites
Group image debrief – optional participation
Arrival on Saturday 1st August – check in commences at 1800
Check out Saturday 8th August – 1200 latest
For those whose flight leaves much later possibility of a stop gap in a beach resort before final departure
You need to be a PADI Advanced Open Water Diver or equivalent and 30 logged dives are required for this safari. All dives, especially some more demanding wreck dives, are subject to diver’s qualification and experience.
EAN or other Nitrox certification required if not training will be provided on the boat at a charge.
Extra Hotel arrangements if you are coming the day before or leaving the day after
Halfboard in Single Room = 50 € per night per person Soft All in per in Single room = 60 € per night per person
Halfboard in Double Room = 35 € per night per person Soft All in Double room = 45 € per night per person
Halfboard in Triple Room = 30 € per night per person Soft All in Triple room = 40 € per night per person
Service Charge & taxes included, Transfer Airport to Hotel/ Hotel to Airport is included (Check in starts from 14:00 H, Check out till 12:00 H, in combination with safari booking early check in or late check out will be arranged free of charge)
On to the dive sites:
Wrecks of Abu Nuhas
Ras Za’tar (Optional site for sunbursts)
Jackfish Alley – Optional site for caves
Ras Mohammed where at that time of the year you can have various shoals of fish
Instead of night dives we will do snorkelling session for split shots or sunset dives
I will be glad to help with ideas for the sites or the shots to take however this is not for beginners so if you don’t know even how to work out your camera works maybe it is not for you. The trip is open to photographers and vdeographers I will shoot both and will provide assistance as required. Below little sample of the video opportunity in Shark Reef
If you are interested in this trip deposit of 25% is due by September 23 2019 full payment by 25 January 2020.
Please use the form to express your interest. In case the cruise it is sold out I will operate strictly a first come first serve basis at time of writing there are five space left so hurry up. In case of cancellation I will also run a wait list. Please inquiry for any other details as well
It has been almost 4 years since my first review of the Nauticam WWL-1 wet wide angle lens and a few accessories later this lens is definitely my all time favourite for underwater video with my GH5.
I do not want to repeat myself and beat to death the topic of sharpness in corners I would rather recap on the other benefits of this lens that really make it unique for underwater video. Obviously this lens is very valid also for still images because of the ability to zoom through but this is not the focus of this post.
So let’s have a look at the three killer features of this lens that make it really special
Field of view
The WWL-1 once combined with the Panasonic 14-42mm MKII (the best lens to combine with the WWL-1 in my view) offers a field of view of 130 degrees diagonal. But what does that really mean?
First the WWL-1 does not compare with a rectilinear lens in fact it is almost a fisheye lens as we can see from those shots of a pool wall.
The barrel distortion is evident correcting the image in lightroom gives an idea although not 100% correct of what is the real field of view of the lens.
What is interesting to see is that the WWL-1 like a fisheye lens offers a much wider diagonal field of view than on the other dimensions.
I have compared the WWL-1 with other rectilinear lenses and with the 8mm fisheye.
Linear Ratio to FE
The table I have prepared uses the equisolid equation for a fisheye lens to map the WWL-1 I have verified the values and I can confirm the WWL-1 is somehow equivalent to 10.06mm fisheye lens.
There are two things that are worth noting, the first is that on the horizontal and vertical axis the WWL-1 is not wider than the Panasonic 7-14mm at 7mm. The other consideration is that with the WWL-1 the 4:3 format frame starts to become a classic 3:2 as the ration width/height is 1.56.
When we work in video at 16:9 we crop out most of the diagonal part leaving the rest of the field of view intact this means that in video mode the lens is much more rectilinear and the barrel distortion more contained.
If we look at a frame at 25mm we can see that at 4:3 the level of distortion is reduced but still present.
.The corrected frame shows the residual distortion.
The level of residual distortion in video mode is pretty negligible at 25mm. At 35mm even in 4:3 mode the WWL-1 is practically straight.
The benefit of the distortion of the WWL-1 is such that if you are shooting large sharks for example the barrel distortion makes those sharks look large in the centre of the frame and when they go out of the frame you don’t have the pull effect of a classic rectilinear lens behind a dome. At the same time if you need to shoot some divers or lines that are straight you can zoom in and still cover a pretty wide field of view.
The other benefit of the WWL-1 is that allows you to use lenses that are stabilised, today any lens at the 7-8mm range on micro four third has no stabilisation which means you need to use the in body stabiliser if available with your camera. For the GH5 this means that choosing a lens like the 14-42 MkII gives you access to Dual IS combining body and lens stabiliser and IS lock that really is useful when finning around. I just want to make sure that I am clear I am talking of this lens
The Panasonic 14-42PZ power zoom is NOT compatible with dual IS so if you use this lens you either have in body or lens stabiliser not both. Obviously if you have a camera without stabilisation like the GH5s or the BMPCC 4K all of this is less relevant but still you can have some stabilisation instead of nothing.
I have not shot a comparative Dual IS vs Lens IS vs nothing in the pool but I am planning to do that soon. I can only say once you have dual IS with IS lock you don’t want to go back.
Personally I think that any dive down to 18 meters in tropical or subtropical water will benefit from a filter but I also believe that conditions may change and in some cases you want to take the filter off. Now most of the rectilinear lenses for the GH5 do not even take a filter but also consider that once you fit one in dome port you are stuck with it for the dive. With the WWL-1 and the Keldan filter if you feel there is too little light and you want to get rid of the filter you can.