Category Archives: UNDERWATER VIDEO

Nauticam WWL-1 on Sony Full Frame what to expect

It has been almost 9 years since my first review of the Nauticam WWL-1 and five years ago I revisited this lens on micro four thirds.

Since the very first release I was told by Nauticam that the WWL-1 had been tested on Sony full frame with the 28mm f/2 lens and since then more lenses have been added to the compatibility list and the WWL-1 itself has had a redesign called WWL-1B, this lens has an integrated float collar and I do not know if there is any difference in the optics but I assume there is none.

Nauticam WWL-1B

Nauticam has since released a number of other water contact optics with dry mount and today you have a choice of at least 3 flavours for your Sony full frame camera that provide the 130 degrees diagonal field of view.

ModelPrice (€)Weight (kg)Diameter (mm)Depth (mm)Max Filter size (mm)
WWL-114241.351569752
WACP-C29302.24170145.572
WACP-146043.9019417682
Summary Table Nauticam 0.36x Water Contact Optics

The three lenses provide the same field of view but they are different in size and mount. A useful way to see is that as the lens physical size grows you require a larger underwater optic.

The Sony E-Mount is still the only full frame format compatible with the WWL-1 in virtue of some really small and compact lenses. As you can see from the table above the WWL-1 rear element is large enough for 28mm lenses that have a maximum filter size of 52mm.

Two E-mount full frame lenses the 28/2mm prime and the 28-60mm zoom are compatible with the WWL-1.

As you move towards the WACP-C you can also use the 28-70mm lens which is one of the worst kit lenses on the market but will give you a longer tele end and finally the WACP-1 gives access to the Tamron 28-75mm and Sigma 24-70mm two lenses that have much higher quality than the smaller Sony lenses but have some restriction in terms of zoom range.

Underwater Performance Context

There are quite long discussions about which water contact optic to get for your Sony full frame once you have the 28-60mm zoom and some comparison in terms of sharpness.

In simple terms you can think of the following equation:

Underwater Performance = Land performance X Port Factor

Port Factor is always less than 1 which means a lens will never do in water as well than it does on land. Looking at my analysis of the 28-60mm corroborated by other test you know before buying any water contact lens that the lens has its own limitations and no matter how good is the port performance will only go down. However this may still be a better option compared to a standard dome port.

I do not have access (yet) to the other two water contact optics however I have a good idea of how the WWL-1 perform and how the Sony 28-60mm performs topside. If you want a refresh look at this article.

To understand how a water contact optic works you can go back all the way to the Inon UWL-100.

The idea of this lens designed for compact cameras is to demagnify the camera master lens to enlarge the field of view. You could then get an optional dome that will enable the lens to expand the underwater field of view from 100 to 131 degrees.

Back in 2015 I compared the Inon UWL-H100 with dome with the WWL-1 and concluded that the WWL-1 was giving better results when used on the same camera. It is now time to see if the WWL-1 can be used also on a full frame system.

Sony A1 WWL-1 Rig

The WWL-1 requires the flat port 45 to be used on a Sony full frame underwater housing. The lens will be attached using the same bayonet adapter that has been available for several years now.

Nauticam Bayonet Mount for WWL-1

I have removed the focus knob from the port as I found it inconvenient. The focus knob may be useful with the flat port but for the WWL-1 that is afocal is definitely not required.

WWL-1 topside view

Once you add the flat port the overall length is very much the same of the WACP-C but this will require an extension ring resulting in overall 30mm additional length.

Overall the rig is very similar in weight to the Canon 8-15mm with the Acrylic Dome Port 5.5″.

WWL-1 front side view

Pool Tests

With the rig assembled I went for a pool session with the objective of finding out what was the overall performance of the system.

What follows are a series of test shots of divers.

David f/8
Kid f/8
f/11 side shot
WWL-1 selfie 28mm
Diver f/10

In general I found the lens to be sharper in the centre at f/8 but closing down to f/11 was required if there was something in the corners.

Edge Sharpness

I was intrigued by a number of discussions on edge sharpness and after several exchanges with Shane Smith he was clear that the lens needs to be stopped down to f/11 for best results.

After the session in the pool I would agree with Shane however I was curious if this was an issue of the WWL-1 or the 28-60mm lens itself.

This image quite simple has something at the edges and has focus in the centre at f/8.

Closeup f/8

You will notice that the part of the frame closer to the camera is fairly blurry.

So I did another experiment placing the slate on the edge.

Fuzzy f/8

The edges were quite fuzzy. I wanted to exclude this was an issue of depth of field so I focussed right on the corner.

f/8 focus on corner

This is the resulting image and is still soft on the edge.

fuzzy f8 focus

I then took the same shot at f/11 with focus on centre.

Closeup f/11

The image at the edges is better. Then moved the slate to the edge.

edge f/11

The image improved overall regardless of the focus point indicating this is not a depth of field issue but some other defect of the lens, most likely as the lens meridional and sagittal resolution are different we have an example of astigmatism.

Edge 100% crop f/11
Blurry f/8 edge focussed on edge

The sharpness improves closing down the lens regardless of where the lens is focussing consistent to the MTF charts.

Looking back at land test shots we can see something very similar.

Edge at f/11 topside
Edge at f/8 top side

In conclusion it is not about the WWL-1 but about the lens itself.

Comparison to Rectilinear lenses

While the WWL-1 can offer a diagonal feld of view of 130 degrees the image is distorted and the lens can only offer 107 degrees horizontally and 70 vertically. Is like saying that the horizontal field of view is similar to a 13mm rectilinear lens while the vertical is is more like 17mm. A fair comparison is probably a 14mm rectilinear lens but as the WWL-1 is a fisheye like optic a direct comparison is not entirely possible. In my opinion as the image is distorted is more appropriate to compare the WWL-1 with a fisheye with teleconverter and when I look at what the canon 8-15mm with kenko 1.4 tc can produce for me the results are very similar, I would say the Canon has in fact an edge however the field of view are not comparable except when the WWL-1 is at the widest and the canon with the tc at the maximum zoom. I would go as far as to say that the canon + TC at f/8 is as good as the WWL-1 at f/11.

Canon 8-15mm with TC at 21mm f/8

Conclusion

If you have the WWL-1 from your previous rig it makes absolutely sense to get the Sony 28-60mm and flat port. This combination will give you decent (but not sensational) shots and work very well for 4K video at reduced resolution. I do not believe that this lens can resolve the full 50 or 60 megapixels of the A1 or A7R4 or A7R5 even topside.

If you are starting from scratch I would recommend to think careful at your intended use case. If you want angles wider than 130 degrees and already have the Canon 8-15mm you may want to check the kenko telecovenverter before you buy a new port as all you need is a 20mm extension ring and a zoom gear.

If you really like the field of view range of 69-130 degrees you need to consider which water contact optic you need.

I am still looking for a test WACP-C but until then my general guidance would be to consider simply if you prefer a dry or wet mount.

A dry mount has the benefit of being ready to go as you hit the water, without the need to remove bubbles between the wet lens and the port. As photographer a dry mount may be the best way forward.

If you intend to use your camera for video and insert filters between the lens and the flat port or you require the lens to be removed in water then go for the WWL-1.

Rigorous comparisons between WACP-C and WWL-1 are not yet available but the first indications are that the difference in image quality is very small therefore I would not loose my sleep there and look more at overall ergonomics.

The final consideration is should you get the WACP-1 instead? Based on my assessment of the Sony 28-60mm I would think this is not particularly wise even if this choice is very popular. Personally I always believe that the master lens needs to be good enough to justify the cost of the water optic so I would like to see how the Tamron 28-75mm performs however no test images are available so I am not in a position to conclude.

In my case having seen what the Sony 28-60mm lens can do I am not planning to invest in a WACP-C but I would be very interested in testing one.

The WWL-1 gets my approval also on full frame but it is not going to give me the same resolution than the Canon 8-15mm or the Sony 90mm macro will give. I look forward to testing some rectilinear lenses to see how those compare and this will happen in a week from now so stay tuned.

Costs to get one for your Sony full frame excluding lens:

  • WWL-1B €1,424
  • Bayonet adapter €102
  • N100 45 flat port €494

Total €2,020 vs WACP-C + N100 Extension Ring 30 €3,333

Nikkor UW15 on Sony Mirrorless for photography – Worth it?

Nauticam makes some really interesting adapters and ports for Sony cameras, one of them allows you to use vintage Nikkor lenses on full frame mirrorless cameras.

I decided to source the UW15 as I am planning to use it for video after seeing the results on the movie Avatar.

The challenge of the Nikkor lenses is that they are entirely manual with aperture and focus knobs. This is generally not an issue for videography which is my intended use but I wanted to check how does this lens work for photography as many people still rave about it.

Lenses compatible with the adapter are UW 15, UW 20 and UW 85 full manual. Later autofocus lenses are not supported.

The Rig

My rig is a classic derivation from wide angle with 8″ and 12″ arm segments and my trusty (!) Sea and Sea YS-D2.

Nikkor 15mm rig

The Nikkor weights around 600 grams and gives almost zero lift so this rig was over 300 grams negative in fresh water.

Before using it you need to assemble the lens on the adapter.

Nauticam Nikonos Adapter

You have two parts that can be removed to allow the lens to mount depending on your preference. I set the lens with the display upright so I could try and see it while shooting.

Nauticam Nikkor adapter top side

The controls are located on the left side side and bottom which is where I normally have my levers.

Nauticam Nikkor adapter controls

On the right you will see the display scales.

Nikkor UW15 Aperture and Focus Display

I have to say I was a bit nervous setting this on my A1 considering that this is a lens that is 25 years old at least but the vacuum test was fine so ready to go to the pool with the friends at Rec2Tec Bletchley.

The UW 15 Construction

The Nikkor lenses were generally rectilinear. The 15mm has a field of view equivalent to 20mm so only 94 degrees on the diagonal.

The approach was to correct the water distortion until such point when the image becomes rectilinear and eliminate other aberrations.

I have to say that the amount of chromatic aberrations is practically non existant.

White balance slate

Rectilinear lenses have gone out of fashion since dome ports with fisheye distortion being the preferred look for wide angle in modern underwater photography. For video though straight lines have a value.

Pool Session

Using this lens on the Sony A1 proved challenging for photography. Nailing the focus using peaking did not feel particularly precise.

Not so sharp focus

Some shots may have been sharp enough on film resolution but with the 50 megapixels of the A1 even the slightest misfocus shows.

Is it in focus?

My productivity was quite low at the beginning as I was trying to get a hand of the lens.

The lens itself is by all means extremely sharp even for my camera.

Grid

I worked out that I could not do what I normally do which is to frame first and focus after as by the time I had nailed the focus things would have moved so I decided to set the focus and move forward or back until I thought I had my target in focus.

The situation started to improve.

DSD student with Instructor David Allen

I felt I had worked out how to use the lens so started looking for some subjects. During those sessions you see all sort of stuff as people practice their skills.

Riding

Considerations on the controls

I believe that the average underwater photographer shooting digital will find it very hard to use this lens and will end up shooting at f/8 or smaller apertures so that focussing becomes easier. The lens is especially challenging as it is not particularly wide so you do need strobe power.

DSD Student

I found really hard the lack of display of aperture and focus position. The lens is designed for much smaller Nikonos housing, with my A1 housing being more bulky you need to actually turn and look at the lens to check your settings so many times I did not have the right aperture of focus and it all was pretty laborious. In a video situation for wide angle this lens will work just fine with set and forget at 4K but to nail focus on a high megapixel camera is a hard task.

When you do get the focus though the image is outstanding.

Just married

I tried a selfie to check the focus scale and it worked well.

Selfie

Consider that the most shots were at f/5.6 or f/8.

Dave

As you have no exif data it is impossible to remember what you shot unless you write it down on a slate.

Is it worth it?

The answer depends on your use case and if you already had the lens.

The following use cases fit the Nikkor UW 15 pretty well:

  1. Videos of sharks or pelagic that do not come too close where ambient light is low
  2. Photos at mid range with fairly static scenes where you want straight lines for example fashion models

The lens is definitely not easy to use for dynamic shots, situations where you need to get very close (as it does not focus very close) and where you need to continuosly adjust focus.

In terms of costs in GBP you are looking at:

£474 Nauticam Nikonos Adapter 37202

£300-500 Second hand Nikkor UW15

Obviously if you already have the lens and you are in one of the above use cases I would recommend you get an adapter and give it a go perhaps looking on the second hand market.

If instead you do not have the lens I would say not to bother unless money is no object, you are in the two use cases above and you have sufficent dexterity to control this lens.

Undewater photography has moved forward a great deal thanks to autofocus and although the Nikkor UW 15 is really sharp getting critical focus right is not easy. When it comes to video where you do not normally use autofocus for wide angle this lens is really interesting.

You can shoot at f/5.6 even f/4 subjects in the distance in ambient light with extremely clear and sharp detail at a fraction of the cost of other water contact optics. If you do not own any of the WACP or WWL I would say the UW 15 deserves some considerations but only if your command of depth of field and focus is very good otherwise it is better to pass.

Moving to Full Frame without increasing bulk or at least not excessively!

Many things have changed since Helen housed her Canon Ixus65 in a polycarbonate housing.

Compact cameras are practically extinct and those left have either a port system as the lens is too long or a shorter 24-70mm equivalent lens which is not useful.

Nauticam developed the N85 port system for Sony APSC (also small form factor) and Micro Four Thirds and since mid 2010s those are the prevaling systems for interchangeable lens system underwater.

APSC in the mirrorless Sony format and today Fuji has lacked native fisheye lenses and been plagued by slow flash sync speed and challenges of battery life.

When it comes to DSLR there is no significant size difference between APSC and full frame when you look at the body but moving into lenses there is a substantial difference with the Tokina 10-17mm being the lens of choice for a compact set up for both Nikon and Canon shooters.

Moving to full frame DSLR has meant historically larger ports bigger lenses and a lot more weight especially if you consider larger domes or the newer water contact optics all in excess of 2Kg and frequently more.

When you look at mirrorless the newer Nikon and Canon systems all use the N120 port system so there is no size difference between DSLR and Mirrorless.

In addition if you are already using N120 dome ports like I am you will soon find out that depending on your housing the weight benefit is not entirely there even for Sony camera whose housing are lighter and use the N100 port system. However housing are in general lighter up to 800 grams less.

Today if you want to have a portable ILC camera for photography you are really only looking at the Olympus/ OM Systems range.

If you have made the choice to get larger N120 ports or you have a Panasonic GH series your housing is already pretty big and moving to full frame will impact only when it comes to certain ports.

Let’s dive into this topic.

Here a first perspective of the A1 housing vs the GH5 housing.

GH5 vs A1 front view

Rear side view

Rear view note how the Sony has joystick controls

And finally top view

Head to Head

You can see that the A1 housing is a bit thicker a bit wider but not a great deal and the GH5 is taller.

Dimensions340mm (W) × 169mm (H) × 125mm (D)
A1 Dimensions
Dimensions331mm (W) × 184mm (H) × 110mm (D)
GH5 Dimensions

Looking at the weight on the scale

NA-GH5 2454 grams
NA-A1 Weight

Difference is 320 grams the weigtht are higher than reported as there is a vacuum valve installed.

This means that as the GH5 system was already heavy due to the clam shell housing the difference in weight will come from the lenses and ports.

As I use the N120 system for wide angle already the difference in that use case would come from larger adapter weight or larger ports.

For flat ports on the N85 system there will be instead a weight disadvantage due to the different diameter but this is less than the delta between N85 and N120.

In my future posts I will show my port system for the Sony A1 that has the objective of:

  1. Reducing bulk without totally compromising image quality
  2. Use as much as possible ports I already had
  3. Reduce the overall number of parts and adapters
  4. Offer complete focal range coverage for wide angle

As you will see my macro choices will not go into a direction of reducing weight or bulk but there is a reason for that. You could argue that by using the GH5 and the N120 system I had already killed portability and that is true however unless you want to shoot native lenses on Olympus system there are no real better options to keep image quality and still be relatively light.

Stay tuned for the next articles that will introduce my choices for:

Index of articles with my choice of lenses and ports (continuosly updated):

  1. Fisheye zoom port
  2. Fisheye
  3. WWL-1 wet lens
  4. Rectilinear lens
  5. Macro

Sony FE 28-60mm f/4-f/5.6 Close up tests

The Sony 28/60mm f/4-f/5.6 is a small lens that was initially provided a kit lens for the Sony A7C a 24 megapixel low end camera.

There have been several discussion on underwater forum about the performance of water contact optics adapters to see what is best etc etc.

However I could not find any proper resolution test for this lens so I thought of giving it a go myself.

Dpreview has a decent sample gallery.

Official Test Data from Sony

You can find the lens specifications on Sony website https://www.sony.co.uk/electronics/camera-lenses/sel2860/specifications

The lens is nothin special mostly plastic but it is weather sealed. It has only 7 aperture blades so this is a lens for snapping around happily topside but not exactly a top of the range device.

The construction comprises 8 elements in 7 groups. Sony publishes the MFT resolution chart for this lens on their website.

Sony has some strange nomenclature however for reference images [3] is at 28mm f/4 and [4] 28mm at f/8.

[5] and [6] are at 60mm less interesting for underwater purposes.

The red lines indicate a resolution of 10 lp/mm which is a really low value (the A1 sensor resolves up to 120 lp/mm). The blue lines indicate 30 lp/mm, The [10] indicates Sagittal and [11] meridional lines.

Read this excellent article from Nikon on MTF to understand how to read the graph.

What graphic [3] is telling us is that as we move away from the centre of the frame both sagittal and meridional lines drop in contrast.

Graph [4] shows that at f/8 the deterioration as we move towards the edge of the frame is more contained neverthless meriodional lines drop considerably.

While we cannot conclude how this lens will compare to other lenses what we see from the MFT is that the 28-60mm as tested performs better at f/8 than it does at f/4 when used at 28mm. In fairness it seems to be the same situation at 60mm but the gap between f/4 and f/8 is much less.

I found a good test here aligned to what you will read here to a good extent.

Practical Home Made Test

I sourced a cushion with a complex embroided decoration.

With the camera on a tripod a remote release and one off camera strobe I took shots at f/4 f/5.6 f/8 and f/11. I run tests with the camera poiting at the centre with field of curvature and off centre with the centre of the cushion at the edges.

Here are my findings.

Centre Performance

800% center crop Left f/4 Right f/5.6

As anticipated the lens is not sharper in the center when wide open.

800% center crop Left f/5.6 Right f/8

At f/5.6 the difference with f/8 is minimal

800% center crop Left f/8 Right f/11

Stopping down to f/11 gives a mild deterioration.

Looking at centre I would say f/5.6 to f/8 is the way to go.

Edge Performance

Let’s see the situation at the edges.

400% edge crop Left f/4 Right f/5.6

f/4 was not better in the centre and is pretty bad at the edge.

400% edge crop Left f/5.6 Right f/8

Stopping down to f/8 sees an improvement the situation is not great though.

400% edge crop Left 8 Right f/11

At f/11 the edges are ok.

So looking at edge performance I would use this lens between f/8 and f/11.

Full resolution examples here

28-60mm 28/4
28-60mm 28/5.6
28-60mm 28/8
28-60mm 28/11

Consideration for use underwater

Looking at the lens in isolation I would think the starting point is f/8 with one stop up or down depending on the situation. This lens is not good wide open and beyond f/11 resolution starts to drop.

Alex Mustard has taken some comparison shots between the WACP-1 and the WWL-1 and his conclusion is that the performance of the WACP-1 at f/4 is similar to the WWL-1 at f/6.3. Based on my tests I would frankly not bother shooting this lens at f/4 the quality is just not there. The starting point would be f/8 and f/11 does not deteriorate edge performance that much but of course needs more light. Wider aperture like f/5.6 may be good for blue water shots.

My opinion is that this lens will not offer amazing sharpness no matter which adapter you use and is likely to stop at 26-28 megapixel in reality if not less depending on conditions, assuming your starting point is a camera with more than 40 megapixels.

it would be interesting to compare the water contact options at the aperture of f/8 and f/11 but we can safely conclude that the 28-60mm is not going to be a champion for ambient light shots in low light because the performance wide open is not great.

If I had to invest into the best image quality I would be looking at a different master lens and a larger water contact optic such as the WACP-1.

Additional Information

I have created some stir on the fact that this lens is quite weak but it actually is.

I took the same shots with my 24-70mm GMII and I can say that there are 3 stops difference at the edges between those lenses

The 24-70 at 28mm at f/4 is the same of the 28-60mm at f/11

This is a 200% crop of the edges

Left 24-70 GM at 28mm f/4 Right 28-60mm at 28mm f/11

Few videos from the Red Sea Image Makers Trip

I only did 4 video dives during the trip and one of them was not really good. This is a short video of the other 3 plus the dolphin experience

Valeri did a much better job with his Sony camcorder in Gates housing and produced this outstanding HDR video

I think it was beneficial for him to be on the boat together as I saw his craft getting better and better during the trip.

The inside of the Thistlegorm are one of the highest quality video examples I have ever seen so well done Val!

I have been thinking if I should do this trip again in the future or switch to something different for example macro in the Philippine I am interested in hearing your views!

Environmental Conditions joy and despair of the photographer

A few weeks ago I went diving in Swanage with BSOUP the British Society of Underwater Photographers that I have recently joined.

I was looking forward to some local diving so when I found out that they were organising a trip I managed to get on.

I drove there the night before and I was number two on the pier the next day.

It was a deceiving clear morning with perfect conditions on land.

I had two cameras one in the housing and one for land use so I took a few snaps.

Once parked on the pier I was informed by two friends that dive locally all the time that it was better to wait when the water level was a bit higher.

At that point it did look like a great day however there was a bit of wind.

I had my GH5M2 with the Panasonic 45mm macro that I acquired last year and has become my favourite macro lens.

I jumped in the water one of the first to find out the visibility was well maybe 1 meter? I could not see the LCD screen of the camera due to the suspended particles and had to use the viewfinder

One of the first things I say was this corkwing wrasse with a massive parasite near its eye.

Unfortunately I did not have a snoot or strobes suited for the challenge so I spend the first dive training myself on how to get the least amount of back scatter. Mind you when there are particles you will have backscatter not matter what you do.

Static subjects are ideal for testing so I had a go at some really simple stuff.

And again some anemone the object was to get the cleanest possible shot.

When I was reasonably happy I moved to some more interesting subject I gave up on blennies as I knew everyone would have shot some and besides my strobes were not the best for the situation and I found a cooperating cuttlefish.

I can tell you that to get this clean shot it took me quite a while but on reflection despite being very low I could not even see a hint of the surface so bad the conditions so I decided to get really close.

I wanted to emulate a profile of a person or perhaps an elephant not sure but I took a number of shots waiting for the tentacles to be in the right position and this is my best shot for the day.

I would say it is quite creepy but after all I had something decent and when I presented the shot in the club review at the sailing club it got some good feedback.

Now with that in mind let’s have a look at some shots taken in clearer water this is from Sorrento Peninsula.

Blenny Gold

You can see that clearer water improves contrast and sharpness as you would expect however as the UK shot was very close the gap is not as big.

And this is a shot from last time I was in the red sea

This is super macro so again suspended particles are not as important.

However if we look at a mid-range shot similar to the whole cuttelfish the situation is very different.

Here we are in Italy.

The Look

And finally here in the red sea.

Napo Lips

For as much as we may love our local dive site there is a degree of adaptation but also a restriction on the variety of shots we can take.

When I was working as resident dive instructor I remember the guidelines we were passed one was really funny and said:

“if the visibility is crap you don’t say that to the guests what you say is today we are going to focus on macro” then you make sure you choose a site where there is some.

I am looking forward to my boat in the Red Sea end of July remember if you follow me on instragram there may be some voucher codes to be used for discount.

If like me you have been trying to make the most of your local dive site you deserve to get yourself in clear water where you can actually see further away than your arm. Of course we do have some good days in England sometimes 5 even 8 meters but I tale Egypt and their 25+ meters any day of the week!

A closing thought on conditions and land photography, in fact even if visibility is not an issue most times unless you have fog, overcast days, excessively clear days do not make great land pictures either so we can say we are always on a quest chasing light and conditions.

Panasonic GH5M2 and GH6 HDMI Lag Optimisation

Key Facts

  • The camera live view is one frame behind due to the image processing pipeline, faster refresh rates reduce delays
  • HDMI latency does not depend on cable length
  • Most monitors have low latency
  • HDMI can carry audio and video and those need to be synchronised: if one of them is slower than the other a delay is introduced to match up
  • Resolution plays a role but not as important as others

GH5M2 and GH6 Lag between LCD and HDMI

  • The camera LCD has a resolution of 960×640 pixels and a refresh rate of 60 fps that can be reduced to 30 fps
  • When recording the camera shows the live view on the LCD with a delay of c 1 frame from real life
  • If you go into the menu HDMI Recording Output and set Sound Output  OFF you can see the real lag between the LCD and the HDMI
  • This lag is typically 2 frames from the LCD 
  • As frame  rate drops the lag increases
  • When the Sound is disabled the lag of the GH6 is generally better than the GH5M2
Measurements Results

Video Tutorial with my recommended settings

Items shown in this video

1. Atomos Shinobi: https://amzn.to/35DmFhD

2. Manfrotto 290 Xtra: https://amzn.to/3sSYggF

3. Manfrotto Light video head: https://amzn.to/3vTCHPc

4. Smallrig Monitor Mount: https://amzn.to/367f22z

5. Smallrig HDMI cable: https://amzn.to/3sVwNe9

6. Panasonic GH6: https://amzn.to/3HTUZlv

7. Panasonic 10-25mm 1.7: https://amzn.to/3KtxAcn

8. Atomos Ninja V: https://amzn.to/3MEKia0

HDMI Optimisation Wrap Up

  • Monitoring has acceptable delays from live time 50-150ms
  • Audio recording introduces a delay of 65ms on the GH5M2 and 35mm on the GH6 
  • The GH5M2 lag  of 190ms in 24p is too high and should be reduced to 160ms
  • There is a bug in the 30p mode on the GH6 as the lag is higher than 24p this needs to be corrected

Panasonic GH6 Power Solutions

The GH6 has the same USB power capabilities introduced in the GH5M2.

In this video I show you what I use with my cameras.

Initially with the GH5 I could only use a dummy battery kit and this will continue to work however it may have challenges with mechanical shutter or very high bitrate codecs of the GH6.

Therefore the recommended solution is a PD Power Bank

Pay attention to the checks you need to do as your power bank needs to deliver 9V 3A which usually means at least 45W better 65W

US

1. Dummy battery kit: https://amzn.to/3sFarxp

2. 65W PD Power Bank: https://amzn.to/35Kh6gW

3. Cheap USB Power Bank: https://amzn.to/3IVhM1u

4. USB C Cable: https://amzn.to/3tnsreQ

UK

1. Dummy battery kit: Currently Not Available

2. 65W PD Power Bank: https://amzn.to/3KgGfih

3. Cheap USB Power Bank: https://amzn.to/3HBGDGk

4. USB C Cable: https://amzn.to/3sGBmcj

Panasonic GH6 my preliminary key observations for Underwater use

I was able to have a 1 hour hands on session with Lumix yesterday and try some of the GH6 features.

Key points

  • Beautifully engineered machine
  • 1 stop dynamic range increase appears to be true
  • LCD design with tilt will make easier to see underwater
  • Records ProRes 422 HQ to CFExpress Card
  • Support HDMI 2.1 (playback only)
  • Battery same as the S5 and newer GH5M2
  • Battery consumption 25 to 35% higher in MP4
  • Significant HDMI lag if you use a recorder (1/4 of a second)
  • Will record to USB with a future firmware update
  • Will record prores raw externally with a future firmware update
  • No battery grip

I am going to do a longer write up once I have tested the camera for land wildife use however I have the following concerns

  1. What is the real battery life when you record ProRes to card instead of the low quality MP4, will it last at least one dive?
  2. HDMI lag is horrible just received confirmation that HDMI recording is capped at 4K resolution This proved to be a red herring as the lag is decreased from the GH5 series see here https://interceptor121.com/2022/03/10/panasonic-gh5m2-and-gh6-hdmi-lag-optimisation/
  3. The lag of the HDMI can be reduced if you use only a  monitor with a few tricks and it only needs HDMI 1.4
  4. The USB recording will be powered by the camera and the battery is already small

My recommendations for a professional grade housing would be:

  • Recording to card either 4K@60 or 5.7@30 depending on your use case
  • Optional monitor to run in 1080p to reduce lag HDMI 1.4 is sufficient
  • PD Power bank inside the housing so you are sure you will not run out for an entire day of shooting

For photography a classic housing would work but then who is going to get this just for photos?

Stay tuned for more information. If there is something you want to know about the camera use the comment feature here.

Panasonic GH5M2 and S series Demystifying Movie recording settings 2022 Update

 

In 2018 I wrote the original article as I had acquired the GH5 and I was faced with a ton of non-sense on which format to use when I was shooting video. With the S series software stack Panasonic has made some changes to the options available and I thought it was about time to refresh the original article. As Before I will focus my analysis on 4K video and ignore other formats. This time I will be looking at the NTSC standard of 29.97 and 59.94 frames per second. This is simply because today majority of content produced by Panasonic consumer digital cameras is consumed online and all computer screen work at 60 Hz refresh rate so shooting anything different than 30 or 60 will result in choppy video. This presents some challenges if you are in a PAL zone and are shooting under artificial lights however for the purpose of this article I want to just ignore this issue, obviously you could shoot 24 fps and hope in a 24 – 30 conversion which is scatty of course. For simplicity I will refer to 30 and 60 fps and not exact values.

Today we have 5 settings for UHD 

  1. 200 Mbps 420 10 Bits Long GOP 60 fps
  2. 150 Mbps 420 8 Bits Long GOP 60 fps
  3. 100 Mbps 420 8 Bits Long GOP 30 fps
  4. 150 Mbps 422 10 Bits Long GOP 30 fps
  5. 400 Mbps 422 10 Bits All-Intra 30 fps.

The last option is only available on the GH5 series and on the S1H. The first option is only available on the S series and the GH5M2. 

Long GOP vs All Intra

The difference between Long GOP and All Intra is that in the Long GOP what is encoded is a group of pictures (GOP) and not separate individual pictures.

Within a Group of Pictures there are different type of frames:

  • I (Intra coded) frames containing a full picture
  • P (Predictive coded) frames containing  motion interpolated picture based on a prediction from previous frames
  • B (bi-predictive coded) frames containing a prediction from previous or future frames

It is important to note that frames are not stored sequentially in a GOP and therefore the GOP needs to be decoded and the frames reordered to be played, this requires processing power.

The reason why H264/HEVC is very efficient is that within a group of picture there is only one full frame and the rest are predictions clearly if the prediction algorithm is accurate the level of perceived quality of long GOP is very high and similar to All-Intra clips.

This is the reason why comparing All Intra and Long Gop using static scenes or scenes with repetitive movement that can be predicted very accurately by the codec is a fundamental error.

So which format should you choose?

In order to understand the workings we need to dig deeper into the structure of the GOP but before doing so let’s evaluate the All-Intra codec.

AVC All-Intra explanation

This codec records at 400 Mbps so with 30 fps this means circa 13.4 Mbits per frame or  1.67 MB per frame and there is no motion interpolation so each frame is independent from the others. The implementation of All-Intra of the GH5 does not make use of CABAC entropy but only CAVLC coding is used, this makes the resulting files easier to read and to edit. The idea of All intra is that you don’t require powerful hardware to edit without conversion in an intermediate codec. However based on my experience this is not entirely through and you need a decent GPU to play it back and edit real time without issues.

If you consider a Jpeg image of your 3840×2160 frame on the GH5 you see that it stores around 4.8 MB per image because there is no chroma sub-sampling so if you wanted to have exactly the same result you would need to use ProRes 4444 to get a comparable quality (this not even taking into account that Jpeg are 8 bits images).

Video uses chroma sub-sampling so only part of the frame contain colours at a given time. Apple in their ProRes white paper declare that both ProRes 422 and 422 HQ are adequate to process 10 bit colour depth and 422 sub-sampling however they show some quality differences and different headroom for editing. If you count 50% for 4.2:0 sub-sampling and 67% for 422 you get around 2.34 MB and 3.5 MB frame sizes that correspond to ProRes 422 and ProRes 422 HQ individual frame sizes.

it would appear that All Intra 400 Mbps would fall short of Apple recommended bit-rate for 422 10 bit colour however practical tests show that AVC All intra at 400 Mbps is perceptually identical to ProRes 422 HQ and uses much less space. We also did some SNR measures time ago with the friend Paal Rasmussen and we did not find significant improvements shooting ProRes 422 HQ vs All-I on card.

Long GOP Codecs

Coming back to the other recording quality option we still need to evaluate how the various long GOP codecs compare relative to each other.

In order to fully understand a codec we need to decompose the GOP into the individual frames and evaluate the information recorded. If you look on Wikipedia it will tell you that P frames are approximately half the size of an I frame and B frame are 25%. I have analysed the Panasonic GH5M2 clips using ffprobe a component of ffmpeg that tells you what is exactly in each frame to see if this explains some of the people claims that there is no difference between the settings.

Link to Panasonic on the H264 implementation is here: documentation

There is unfortunately no documentation of the HEVC implementation that I have found to date.

200 Mbps 420 10 Bits Long GOP 60 fps Analysis

An analysis with ffprobe shows a GOP structure with N=30 and M=1 where N is the length in frames of the group of pictures and M is the distance between I or P frames.

This codec does not have B frames but only P frames.

Analysing a set of I frames of a fixed subject at 60 fps resulted in a frame size of 1.16MB for the I frames. This value is quite low however we need to understand that HEVC is much more efficient than H264. 

I shot this test video time ago comparing the recording of this codec with a Ninja V in ProRes 422 HQ. As you can see no major differences however I have not pushed the grading in the clip.

The speed ramps in this video use this codec

 

150 Mbps 420 8 Bits Long GOP 60p Analysis

An analysis with ffprobe shows a GOP structure with N=30 and M=3 where N is the length in frames of the group of pictures and M is the distance between I or P frames.

So each Group of Pictures is made like this

IBBPBBPBBPBBPBBPBBPBBPBBPBBPBB before it repeats again.

Analysing a set of I frames of a fixed subject at 30 fps resulted in a frame size of 1.26MB for the I frames.

One very important aspect of the 150 Mbps codec is that as the GOP is double the length of the single frame rate 100 Mbps codec there are the same number of key frames per second and therefore it is NOT true that this codec is better at predicting motion however the additional frames result in better slow motion performance than what is done in software in majority of cases.

100 Mbps 420 8 Bits Long Gop 30 fps Analysis

An analysis with ffprobe shows a GOP structure with N=15 and M=3 where N is the length in frames of the group of pictures and M is the distance between I or P frames.

So each Group of Picture is made like this

IBBPBBPBBPBBPBBP before it repeats again.

Analysing a set of I frames of a fixed subject at 30 fps resulted in a frame size of 1.49MB for the I frames which is the highest if we exclude All I.

150Mbps 422 10 Bits Long Gop 30 fps

An analysis with ffprobe shows a GOP structure with N=15 and M=1 which means this codec does not use B frames but just I and P frames so the GOP structure is as follows:

IPPPPPPPPPPPPPP before it repeats again.

Analysing a set of I frames of a fixed subject at 30 fps resulted in a frame size of 1.25MB for the I frames.

H264 Codec Ranking for Static Image Quality UHD

So in terms of absolute image quality and not taking into account other factors the Panasonic GH5M2 and S series Movie recording settings ranked by codec quality are as follows:

  1. 400 Mbps 422 10 Bit All intra 30 fps (1.67 MB per frame)
  2. 100 Mbps 420 8 Bit Long Gop 30 fps (1.49 MB per frame)
  3. 150 Mbps 420 8 Bit Long Gop 60 fps (1.26 MB per frame)
  4. 150 Mbps 422 10 Bit Long Gop 30 fps (1.25 MB per frame)

The 100 Mbps  and 400 Mbps codec are marginally different with the 150 Mbps long GOP really far away.

Note that as the technology is different I cannot directly compare the new 200 Mbps codec however based on visual impression and ability to grade I would recommend this over the 150 Mbps 420 8 bits

Conclusion

If you have a camera that has the 400 Mbps All Intra this remains the best format  to use. V90 cards have dropped in price and are now available up to 256 GB. Unfortunately this option is only available on the GH5 series and on the S1H.

If you have a camera that does not have the All-I you can of course purchase an external recorder that in some cases will allow you to shoot RAW however this is not necessarily going to give better image quality and will definitely extend your processing time.

My revised advice, if your camera does not have the ALL I and you don’t have an external recorded, is as follows:

  1. Use the 100 Mbps Long Gop codec it is very efficient in the compression and the perceived quality is very good. You need to get the exposure and white balance right in camera as the clips may not withstand extensive corrections. There is a risk with footage with a lot of motion of some errors in motion interpolation that can generate artefacts but this based on experience is not very high. 
  2. Use the new 200 Mbps HEVC for double frame rate it is not hard to process as HEVC 10 bits has hardware acceleration on all platforms.

Generally there appears to be no benefit using the internal 422 10 Bit codec nor the 420 8 bit double frame rate due to the limitations of the GOP structure, in addition the lack of hardware acceleration for H264 10 bits means you will need to convert the files for editing and they do not open with standard programs or load on phones or tablets. The same is true for All Intra but at least you can edit it ok.

To conclude this is a summary table with all key information

Screenshot 2022-01-24 at 18.01.50

Additional Considerations

A certain number of GH5 users have upgraded to the S5, I was one of them until I sold the camera after 1 month of using and after buying a Ninja V. If you are a Panasonic S1/S5 user you need not only to contend with recording time limits but also with lack of codecs on the camera to fully use the potential that it has. You need to add an external recorder to really see the benefits because in real life situations you are not shooting a step chart so the dynamic range is destroyed by compression quality and errors and SNR drops. It would be interesting to test how does the GH5M2 400 Mbps compare with one of the S cameras using the 150 Mbps 10 bit codec but this is not something I did. I would only warn everyone going down that path that you may get less than what you think and you may require additional hardware to get there. Take also into account that S series only shoot 50/60 fps in APSC/Super35 mode and that in full frame mode there is a substantial amount of rolling shutter that makes pans and tilt practically not possible.