Category Archives: Micro 4:3

Fisheye Zoom for Micro Four Thirds

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.

Wolfgang Shreibmayer started a trend time ago in WetPixel https://wetpixel.com/forums/index.php?/topic/61629-canon-ef-lenses-on-mft-cameras/ to use full frame lenses and in this post I want to do a deep dive on what is for me the most interesting lens option the Canon 8-15mm fisheye.

This lens on full frame can be used for a circular and diagonal fisheye but Wolfgang has devised a method to use it as an 8-15mm fisheye zoom on MFT.

Part list – missing the zoom gear

What you need are the following:

  • Canon EF 8-15mm f/4L fisheye USM
  • Metabones Smart Adapter MB_EF_m43_BT2 or Viltrox EF-M1 Adapter
  • A 3D printed gear extension ring
  • Nauticam C-815Z zoom gear
  • Nauticam 36064 N85 to N120 34.7mm port adapter with knob
  • Nauticam 21130 30mm extension ring with lock
  • Nauticam 18810 N120 140mm optical glass fisheye port

The assembly is quite complicated as the lens won’t fit through the N85 port. It starts with inserting the camera with no lens in the housing.

GH5 body only assembly
Camera in housing without port

The next step is to fit the port adapter

Attach N85 N120 Metabones adapter

Then we need to prepare the lens with the smart adapter once removed the tripod mount part.

Canon 8-15 on Metabones Smart Adapter IV

As the port is designed for the speed booster the lens will be few mm off therefore the gear will not grip. Wolfgang has devised a simple adapter to make it work.

gear extension ring
Zoom gear on lens

This shifts the gear backwards allowing to grip on the knob.

3D design is here

Lens inserted on housing

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.

Fisheye dome and extension
Full assembly top view
Side front view

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.

Disassembly

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.

Focal lengthHorizontalVerticalDiagonalHorizontal Linear EqWidthHeightDiagonal
8130.995.9170.217.31321.64
9114.984.7147.8
10102.575.9131.06.9
1192.668.7117.88.3
1284.562.9107.29.5
1377.757.998.410.8
1472.053.790.911.9
1567.050.184.613.0

Wolfgang has provided me with some shots that illustrate how versatile is this set up.

8mm end surface shot
Caves 8mm
15mm end close up
Dolphins at 15mm
Diver close up at 8mm
Snell windows 8mm
Robust ghost pipefish @15mm

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.

Amazon links UK

Canon EF 8-15 mm f/4 fisheye USM lens

Viltrox EF-M1 Mount Adapter

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.

Using Rectilinear Wide Lenses Underwater

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:

Olympus 9-18mm

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.

Olympus 7-14mm

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.

Panasonic 7-14mm

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.

Steering Wheel Truck
Panasonic 7-14mm with acrylic dome 9mm f/8
Exploring the Chrisoula
Panasonic 7-14mm with acrylic dome 7mm f/5

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.

Panasonic Leica 8-18mm

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.

Encircled
Panasonic 8-18mm in 7 acrylic dome f/8
Sunset Neat
Panasonic 8-18mm at 8mm f/10

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.

Perspective Distortion

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.

Shot at f/2.8 with Panasonic 8-18mm at 8mm shows sharp corners
Image with objects in edges at 8mm

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.

Same scene at 9mm

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.

Barrel distortion applied -60 8mm

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!

Barrel distortion -30 9mm

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

16:9 crop still showing the edge ‘pulling’ at 8mm

16:9 crop looks straight at 9mm

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.

Bike on Hold 2
Bike in hold 2 on SS Thistlegorm Panasonic 8-18 at 8mm
Bubbling Bike
Shot at 7mm showing the front tyre pulling outside the frame

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.

which macro lens to pick for your gh5 or micro four third

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:

  • Olympus 30mm
  • Panasonic 30mm
  • Panasonic 45mm
  • Olympus 60mm

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

DxOMark Comparison on Olympus 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.

Let see why

Using an online calculatore like Dofmaster https://www.dofmaster.com/dofjs.html

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)

Aperture f/11

Result Total depth of field 0.3cm

Now enter

Focal Length 60mm

Distance 21 cm (as it achieves the same magnification)

Aperture f/11

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)

Shot at 60mm
Shot at 44mm
Shot at 29mm

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.

Shot at 60mm
Shot at 44mm
Shot at 29mm

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

Rhinopia Olympus 60mm

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:

  1. Working distance
  2. 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.

Hairy frogfish Olympus 60mm

Conclusion

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.

Getting the best colors in your underwater video with the panasonic gh5

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:

  1. Sharp
  2. Colorful
  3. Contrasty
  4. Clean

Those 4 characteristics are tightly related to:

  1. Resolution
  2. Color depth
  3. Dynamic range
  4. Low Noise

Resolution

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.

Color depth

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.

Dynamic Range

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

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.

Diving Conditions

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:

  1. Ambient light shots
  2. Artificial light shots
  3. 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.

Chrisoula K Bow
Chrisoula K Ambient Light 5 meters

Color Filters

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)

Filter in action at 10 meters

Right now there are predominantly 3 filters on the market:

  1. UR PRO
  2. Magic filter
  3. Keldan Spectrum

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.

FilterLight LossTypical Max Depth
Magic Filter1 2/3 Ev15 meters
Keldan Spectrum -22 stop (WWL)12 meters
URPRO 1 2/3 Ev18 meters

This image gives an idea of the 3 filters as you can see they are very different one from the other.

Keldan top URPRO bottom Magic filter

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.

FilterCyan Strength
Magic Filter2 stops
Keldan Spectrum1 1/2 stops
URPRO3 stops

The above value are based on my experience use at your own risk especially with different lights.

Square Cyan 2 stops Round Cyan 3 stops

To give an idea I overlapped the filter to my iPhone lens

This is the shot without any filters

Original Shot

URPRO and Cyan 3 stops (darker)
Magic filter and cyan 2 stops accurate
Keldan and cyan 2 stops accurate

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

five in a row
My own filter and Cyan 3 stop note that the light is coming from the other side

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.

Artificial lights

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.

http://www.magic-filters.com/need.html

NAUTICAM WWL-1:THE BEST WIDE ANGLE LENS FOR UNDERWATER VIDEO (ON THE GH5 AND OTHER MICRO FOUR THIRDS)

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.

WWL-1 at 14mm wide end

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.

WWl-1 at 14mm with distortion correction at 100

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.








Horizontal  25 50 100 200 FOV Linear Ratio to FE
7-14mm@7 62 124 248 496 102 57%
8-18mm@8 54 108 216 432 94 50%
12-60mm@12 36 72 144 288 72 33%
WWL-1 61 122 244 488 102 56%
Fisheye 8mm 109 218 436 872 130 100%







Vertical 25 50 100 200 FOV
7-14mm@7 46 92 184 368 86 84%
8-18mm@8 41 82 164 328 78 75%
12-60mm@12 27 54 108 216 57 49%
WWL-1 39 78 156 312 75 71%
Fisheye 8mm 55 110 220 440 96 100%







Diagonal 25 50 100 200 FOV
7-14mm@7 77 154 308 616 114 13%
8-18mm@8 68 136 272 544 107 12%
12-60mm@12 45 90 180 360 84 8%
WWL-1 107 214 428 856 130 18%
Fisheye 8mm 583 1166 2332 4664 170 100%

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.

14mm WWL-1 cropped at 16:9

If we look at a frame at 25mm we can see that at 4:3 the level of distortion is reduced but still present.

WWL-1@25mm

.The corrected frame shows the residual distortion.

WWL-1@25mm corrected
WWL-1@25mm 16:9 crop

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.

Stabilization

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

https://www.panasonic.com/uk/consumer/cameras-camcorders/lumix-camera-lenses/lumix-g-lenses/h-fs1442ae.html

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.

Filters

The final killer feature of the WWL-1 is that it gives you access to the Keldan Spectrum filters review here http://wetpixel.com/articles/review-keldan-spectrum-and-ambient-filters-by-massimo-franzese

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.

Keldan filter in action

How to choose the best close-up lens for your underwater MFT rig

How many times you see practically new close up lenses being sold on eBay after sitting for years in a cupboard? Have you ever experienced the frustration of buying a close-up lens to find out it did not add anything to your set up?

There is a lot of confusion in terms of what is that you are really getting when you buy an underwater close-up lens. In most cases lenses are specified in diopters, in some other cases with a magnification factor, in few cases with the focal length.

The focal length is probably the most useful of those specification because in a traditional diopter the following formula is valid if you approximate the lens to converge in the rear element:

Working distance ≤ Focal length – physical length of the close-up lens

For example for a Subsee +5 diopter the focal length is 1000/5=200mm the lens is 32mm therefore the working distance is less than 168mm.

Now on its own this means very little. Depending on the camera we use a distance of 168mm may be a great improvement or no improvement at all.

To understand why we need to look on our camera and find the little symbol that indicates the focus distance reference mark.

While for DSLR the shooting distance is typically calculated from the front on the lens for micro four third you need to use this obscure symbol.

IMG_1394
P1055540

Once we locate the reference mark we need to identify the corresponding reference on the housing we can use the other dials as starting point. In this case the mark is approximately in the middle of the cold shoe.

When we put the camera in the housing we can then look up the specifications of the lens and calculate the minimum shooting distance. For example for an Olympus 60mm this value is 19cm.

P1055541

We take note of this point and then measure the distance between the glass and the minimum working distance on land.

P1055543

This works out to be around 9cm. We now need to consider that once immersed in water this distance will be multiplied by 1.33 to become 12cm.

It follows that any diopter with a focal length close to 12cm or longer is not going to be effective for our camera and lens combination. More likely we need something that can focus substantially closer or the benefit will be minimal. Assuming we half the physical working distance between the port and the subject we need something around 60-80mm focal length which considering the length of the lens itself could mean getting 2cm away from the subject.

Continue reading How to choose the best close-up lens for your underwater MFT rig

Nauticam WWL-1 with Macro Port 29 for Micro Four Thirds

Nauticam has recently released a new Macro port 29 that is shorter than the 35 and is designed for optimal compatibility with the following lenses and the WWL-1 Wet lens.

  1. Olympus M.Zuiko Digital ED 14-42mm f/3.5-5.6 II R
  2. Panasonic Lumix G Vario 12-32mm f/3.5-5.6 ASPH Mega OIS
  3. Panasonic Lumix G X Vario Power Zoom 14-42mm f/3.5-5.6 Power OIS

I have had the port and wet lens for a few days and those are my observations with the Panasonic lenses as I do not own the Olympus.

In general terms none of those lenses are amazing in terms of optical quality and only the Panasonic lenses are stabilized. This is not so important for still images but an advantage for video.

Photozone has tests of all the three lenses

Olympus Test

Panasonic Vario G X PZ Test

Panasonic 12-32 Test

The Panasonic power zoom is better than the Olympus however the lens has issue of vignetting and pretty high chromatic aberration. The Panasonic 12-32mm is surprisingly good and has similar resolution and less issues of fringing.

I attached the 29 Macro Port to my GX7 housing and took some tests shots in the sink with the WWL-1 petals touching the subject.

Panasonic G X 14-42 PZ Port 29
Panasonic G X 14-42 PZ Port 29

The image is wide and the corner sharpness is great with minimal to no chromatic aberrations.

The 12-32mm lens does not vignette at wide end and gives similar performance to the PZ lens with the benefit of increased field of view.

Panasonic 12-32mm Port 29
Panasonic 12-32mm Port 29

The shots are taken at f/4 ISO 1600.

For comparison I mounted the 4.33″ dome and the 8mm fisheye and took a similar shot.

8mm Fisheye
8mm Fisheye

The field of view is wider but of course distortion in the corners is very high to the point they become garbled.

Clearly if you do need a fisheye lens the 8mm is still the choice however the WWL-1 has the advantage that you can use the full zoom and a field of view of around 130° with a 28mm equivalent lens and around 135° with 24mm equivalent.

One thing that is interesting is the use of the 12-32mm with the Macro 29 port combined with the Panasonic GH4 in 4K.

The crop factor of 1.2x means that the focal length with this lens at 4K 16:9 is 31.38mm. This makes this port compatible with a number of flat wide angle lens of the old generation.

Specifically the old Inon UWL-100 would give a field of view of 100° equivalent to 18mm in 4K. The additional benefit is that you can use the Ikelite UR/PRO push on filter and the full zoom. At the tele end 83.7mm may be a bit short however the fact that you have a fully rectilinear lens and you can use a push on filter is a big advantage.

The Macro port 29 is also compatible in normal mode with the Inon UWL-H100 at 24mm equivalent as per image.

Inon UWL-H100 Port 29
Inon UWL-H100 Port 29

The field of view appears narrow as the lens can get closer to the subject compared to the WWL-1. The optical quality is excellent with minimum fringing.

In summary the Macro Port 29 is a must purchase for the following users:

  • 4K Panasonic GH4 video users
  • 4K Panasonic GX8 Users
  • HD and Still images micro four third users wanting a full wet lens set up

The 12-32mm lens also give almost the same field of view of the Panasonic 7-14mm with wide angle port at much lower cost when coupled with an Inon UWL-H100 allowing use at apertures of f/4 and f/5.6 with one to two stops advantages on the 7-14mm.

On a final note for the users of the Macro 35 port Nauticam has now released the zoom gear for the Panasonic 14-42mm II Mega OIS. This lens is better than all of those discussed in this post in terms of optical quality and it comes as kit lens on lower end Panasonic cameras. If you already have the Macro Port 35 and a kit lens or if you don’t have any lens or port this is definitely the best option in terms of cost and optical quality

Nauticam bayonet mount for wet lenses

Nauticam entered the wet lenses market with their SMC close up wet lens that was optimized for DSLR.

Then it released the CMC compact macro converter for compact cameras and micro four thirds and finally the Wet Wide Angle Lens I that is compatible with compacts, micro four thirds and also full frame cameras with 28mm equivalent lens.

Up to now all lenses were using the traditional M67 mount as most of the lenses, even the close up ones, are pretty heavy this means going for the dive with the same lens. Nauticam has developed the flip diopter adapter for flat ports to overcome this issue.

Flip Diopter on Nauticam RX100 IV
Flip Diopter on Nauticam RX100 IV

The flip diopter is a good solution for micro four thirds and DSLR but looks rather cumbersome on compacts as the image shows.

I asked Nauticam for a bayonet adapter and specifically if they could develop something for the Inon LD bayonet system that so far has been the reference for wet lenses for compacts and micro four thirds cameras.

LD mount converter on RX100 IV
LD mount converter on RX100 IV

Edward told me that due to the fact that the WWL-1 lens rear element is so large the Inon LD system was not an option so they went off and developed their own system.

M67 bayonet mount converter
M67 bayonet mount converter

I would like to thank Nauticam again for making those parts available before general availability.

Looking a bit closer to it you can see that due to the specific construction with two concentric rings you need a special tool to apply the adapter on the port.

M67 bayonet mount converter The large item is to attache the mount to the port
M67 bayonet mount converter
The large item is to attache the mount to the port

Obviously as the Nauticam lenses use an M67 thread new adapter needed to be developed.

Mount converter for CMC/SMC
Mount converter for CMC/SMC

Nauticam does not use ABS plastic and uses aluminum for all their parts.

Now that the items have a bayonet adapter there is a need for a lens holder to put on the arms.

Lens holder looks too big for a 5" arm segment
Lens holder looks too big for a 5″ arm segment

The lens holder is too big for a standard 5″ segment but looks in proportion with a longer segment.

Lens holder on 8" arm segment
Lens holder on 8″ arm segment

The adapter is larger than the LD mount and a bit big for compacts to the point that even with a tray the adapter tips the rig back.

Another challenge is that this system is designed for Nauticam lens that have protruding rear element so when used with standard lenses there is a gap between the port and the wet lens that can be counter productive, not the end of the world and frankly the Inon system has the same problem. This however means that if you wanted to use this system with a different wide angle wet lens this would be suboptimal.

I am waiting for Nauticam to ship me back the WWL-1 so I can show how that lens performs on this system.

Another observation of course is that if you use this system for wide angle the super heavy WWL-1 and the fact that the adapter only works on a normal segment means your rig will be very heavy in water. I am going to discuss with Nauticam the possibility to have the adapter on a float arm however their carbon arms do not have any mounting point to be used.

Stay tuned for a full review of this adapter with the new 29 macro port that looks very promising for video.

Nauticam NA-LX100 4K Video Review

Following the previous review that was dedicated to still images we now go into the subject of 4K video with the Panasonic LX100 and related Nauticam LX-100.

Currently there are only two compact cameras that produce 4K video the Sony RX100 and the Panasonic LX100.

The housing for the Sony RX100 has a traditional M67 port whilst the LX100 uses the N50 compact port system.

This means you can use all your wet lenses with the RX100 without specific adapters. The LX100 has however a number of benefits.

This table compares the field of view of the two cameras in 4K video mode.

LX100
4K Horizontal FOV Vertical FOV Diagonal FOV Sensor width 35mm 3:2
26.00 71.90 44.40 79.50 15.80 23.86
81.00 26.20 14.90 29.90 15.80 74.40
RX100
4K Horizontal FOV Vertical FOV Diagonal FOV Sensor width 35mm 3:2
28.00 67.90 41.50 75.40 11.85 26.73
80.00 26.00 14.80 29.60 11.85 76.37

When the camera shoots in 4K mode the focal length remains the same however the camera uses a smaller part of the sensor. A normal micro four third sensor measures 17.3×12 mm whilst the 1″ sensor of the RX100 is 13.2×8.8 mm. Note that the LX100 does not use the whole sensor due to the multi aspect format that keeps the diagonal field of view unchanged regardless of the image format.

What we can see in the LX100 table is that although the focal length in 4K is 26mm the horizontal field of view is the same of a full frame camera with a lens of 23.86mm this means the field of view in 4K should be slightly wider than a picture taken by the LX100 in 4:3 format.

I put the camera on a tripod and took two sample shots, this is the first at 24mm in 4:3 format that I then cropped to 16:9.

4:3 Crop to 16:9
4:3 Crop to 16:9

This other shot is from exactly the same position taken extracting a 4K frame from a small video.

4K Photo 16:9
4K Photo 16:9

As stated the horizontal dimension is just a few mm wider in 4K 16:9.

What this means is that this is the same that any normal camera with a 24mm lens that then is cropped to movie format in terms of field of view.

The Sony RX100 does not have a multi aspect sensor and therefore the horizontal field of view drops more.

With the short port on the LX100 using a wet lens like the Inon UWL-H100 we can achieve more than 97° horizontal which is very wide and zoom all the way to 79° and if we use a wetmate or the mini dome cover the other range between 72° and 50°.

Practically the LX100 with wet lenses and wetmate or minidome gives you access to focal lengths between 15.5-21mm and again 24-35mm is like having an 8-18mm lens on a micro four third which is good for whale sharks and mantas this is even wider than the 7-14mm lens on a Panasonic GH4 in 4K and the LX100 has a (weak) optical stabiliser on the lens.

The RX100 mark IV instead can only cover between 96° and 90° before the wet lens stops working properly and we jump to 68° if using a wetmate.

UWL-H100 Flat Test Cards
UWL-H100 Flat Test Cards

This shot taken at around 15cm shows a nearly rectilinear and very wide image.

In short if you are after some super wide angle in 4K the LX100 is definitely the way to go.

From an ergonomic point of view I shoot video in shutter priority and let the camera work out ISO and aperture, this is relatively easy to do with the LX100 although the absence of custom memory modes on a mode dial is painful.

A control that can be quite useful due to the tendency of the LX100 to go focus hunting is to set the ae/af lock button to af-on. This requires the shutter to be set in release priority with this control you can use manual focus and force the LX100 to refocus when you hit the af-lock. This is a very useful feature.

Update 28 September the method described to fight focus hunting does not work in 4K. There is going to be another post with the best settings for 4K video for the LX100.

For what concerns macro both the LX100 and RX100 present their challenges due to the short zoom lens, the LX100 more so due to the horrible rectangular port. It can be argued that you can’t shoot wide and macro with the LX100 whilst you can do that with the RX100 however the strength of the LX100 is certainly in its very wide lens and the short port that combined with a flat wide angle lens can produce an extremely wide field of view able to cover practically almost any wide angle scene.

For macro the GH4 and upcoming GX8 are probably going to be better placed due to the higher crop factor giving focal lengths in excess of 100mm using the 14-42mm lenses.

If you want to get into 4K video and your focus is primarily wide angle the LX100 is an excellent device.

The WWL-1 on a Nauticam LX100
The WWL-1 on a Nauticam LX100

 

Nauticam NA-LX100 housing and port system review

Nauticam has given me the opportunity to test the housing for the Panasonic LX100 priced at $1,200 or £922 in UK.

As anticipated some time ago this housing features the new N50 mini port system for compact.

NA-LX100 aperture and format dial
NA-LX100 aperture and format dial

The housing comes with the rectangular port as a standard, as the LX100 has a 24mm equivalent lens and the lens extends quite a lot between the shortest and longest focal length it is not possible to use an M67 long port or there will be vignetting.

In order to install the camera you need to set the aperture to f/16 and the aspect ratio to 4:3 with focus mode in normal and lift the zoom lever. Likewise to take the camera out of the housing.

LX100 housing preparation
LX100 housing preparation

Unfortunately as mentioned several times on this blog pincushion distortion severely affects the image at focal lengths shorter than 35mm equivalent as our in water test shot demonstrated. If you zoom in the corners you can see also extensive blur and chromatic aberrations.

LX100 flat port at 24mm
LX100 flat port at 24mm

Furthermore the lack of an M67 port means you now need the Nautical flip diopter for rectangular port that costs $220 or £170.

When you eventually get to put a diopter on the lack of zoom means that magnification with traditional lenses is quite limited.

UL-165
NA-LX100 UCL-165

The frame width is 62mm with a single Inon UCl-165 and goes to 5cm when we stack another UCL-330.

UCL-165+330
NA-LX100 UCL-165+330

Image quality is ok except some blue fringing at the borders.

A single UCL-100 gives a frame width of 42mm.

UCL-100
NA-LX100 UCL-100

Apparently the Nauticam CMC ($320 or £240) gives 32mm frame width that is adequate for macro.

So if you are into macro you need to invest $1,200+$220+$320=$1,740 to have some decent magnification.

If you possess many clamps and cold shoe ball mounts you can buy an Inon M67 lens arm and use the lenses you have saving some $$$ but the magnification is limited unless you get the CMC.

For semi-wide angle a mini dome port is available at $280 or £216.

N50 3.5
N50 3.5″ Mini Dome

This restores the field of view in air however you can only zoom to 40mm before the camera can’t focus anymore. I have even tried with dry diopters on the camera there is no improvement.

Optical quality is great.

LX100 Mini Dome 24mm
LX100 Mini Dome 24mm

Probably the most useful port is the N50 short port that has an m67 thread and allows to use wet wide angle lenses.

N50 Short Port
N50 Short Port

I went to Swanage but got the tide wrong visibility was shocking still gives an idea of the image quality of the LX100 with the Nauticam WWL-1 wet lens.

SWANAGE (4 of 4)
Atlantic Ocean Anemones

SWANAGE (3 of 4)
Kelp?

Upside down
Upside down

SWANAGE (1 of 4)
Myst!

If you have a Nauticam wet mate you can also use it with the short port and achieve the same or better sharpness than the minidome thought with some residual chromatic aberration.

LX100 Short Port Wet Mate 24mm
LX100 Short Port Wet Mate 24mm

The big benefit is that if you find that your wet wide angle lens is too wide for what you are shooting you can change lens without changing the port.

NA-LX100 rear buttons
NA-LX100 rear buttons

For what concerns the ergonomics of the LX100 they are quite intuitive on land.

One of the characteristics is the lack of a mode dial.

You have an auto position  for shutter speed and aperture and if you leave them as such the camera shoots in program mode.

Once you move the aperture the camera goes in aperture priority mode. Probably the worst situation is the shutter dial that once touched has to come down all the way from 1/4000 to whatever you need it to be.

Also you don’t have thirds of exposure for the shutter dial and for example to get 1/50 you need to go to 1/60 and then use the rear dial.

I found the ergonomics of the camera in water particularly annoying as I was shooting with gloves. I did like the nauticam trigger system for the shutter however the amount of hardware of the nauticam tray and its weight are not really an option for me.

The Panasonic LX100 is a very interesting camera on land but in water ends up quite uncomfortable and expensive. The housing with the 3 ports comes at $1,200+$180+$280 if you add the Nauticam CMC and the WWL-1 you end with a whopping $3,195 the camera costs another $800. Total investment $4,000.

This is a lot of money in my opinion considering that with another $300 you can get a Panasonic GX7 with GX7 housing, an Olympus 60mm with 65 macro port and a Panasonic 8mm fisheye with 4.33″ dome. The LX100 and GX7 share the same sensor but there is no doubt that the macro performance of a dedicated lens as well as the fisheye of the 8mm lens have no comparison.

In conclusion the Panasonic LX100 with NA-LX100 is a bit of a flop for stills the only use that I can think of is wide angle 4K video with the short port and a wet lens but other than that I don’t see how Nauticam is going to sell many of those units.