Setting up your GH5 for HLG HDR capture

We got our GH5 ready for HDR capture in the previous post so how do we make the most of it?

If you have an external recorder or monitor that supports HDR it is easy! Also if you do you probably have a fair bit of money and you are not reading this blog…

Currently Atomos recorders that can be housed all support HDR including HLG

DSC_9783_2c838594-1601-42d1-b145-40821cd34bb2_1024x1024
Nauticam Atomos Flame

The Nauticam Atomos Flame available at list price of $3,650 will house the Shogun Inferno, Shogun Flame, Ninja Inferno and Ninja Flame

On the Atomos website you can see that for the GH5 the products recommended are the Ninja and Shogun Inferno there first is priced at $995 and the second at $1,295.

There is a difference of $300 between the Shogun  and the Ninja  however the Shogun  provides an SDI video port that may turn out quite useful in grading phase. So if you got to the point of spending $3,650 for the housing I would definitely invest the extra $300 needed for the Shogun Inferno.

Once you get a recorder you can set up the GH5 to output 4Kp50/60 at 10 bit and be happy. The HDR screen of the Atomos device will provide the real time monitoring you need to expose footage properly in HLG. It is not my intention to start a debate about log vs HLG there is plenty of material out there.

A very good video is here

If you don’t have a recorder you are left to the GH5 screen that does not support HDR so how are you going to expose correctly? You have a couple of tools available.

The first one is Zebra Patterns that can be accessed in the Monitor subsection of the menu.

There is a great tutorial on YouTube

Now if you are working in HLG you will notice that the maximum value that can be set is 95% this is because luminance in HLG is limited to 64-940.

If you look on ITU website you can see that white ranges between 69 and 87 in HLG so using Zebra we can still attempt at exposing properly without an HDR monitor.

If you do have a reference white balance card you should set the Zebra to 75% as this is the reference for white if you are in the field without a reference your value should be set to max 90% to ensure you don’t blow highlights. Now you will find some website that tell you 95% is fine too but you do want to leave a bit of headroom. If you want you can set Zebra 1 to 75% and Zebra 2 to 95% so you cover all eventualities.

So once you have set the Zebra the next step is to decide if you want to use HLG View Assist or not. Here you have three options:

  1. Off
  2. Mode 1
  3. Mode 2

Off leaves the display in REC709

Mode 1 gives priority to background areas for example the sky

Mode 2 gives priority to the main subject

The 3 modes are really a progression of brightness, when Off the image looks completely desaturated and Log like. In Mode 1 the image appears to have a preference to show shadows in Mode 2 the image looks the brighter and the most punchy making it easy to work on the foreground but crashes the black and shadows quite a bit.

No matter what you select the Zebra value remain unchanged.

The final setting that can be useful is the Waveform monitor which is accessible in the creative video menu. As the Zebra this gives you a real time display of the image within a diagram that on the horizontal axis represent the image left to right and on the vertical has the signal. This is practically a spacial representation of your image and has the same intensity of the Zebra from 0 to 100. So anything too dark on the bottom won’t be visible and things above max will be clipped.

There are several tutorials available on YouTube

So in essence you could try to expose correctly using Zebra and waveform monitors on the GH5 LCD display but let’s face it the screen is tiny and underwater you won’t be really able to use it effectively. If you have an external monitor or recorder this becomes more useful and something to effectively try.

If you are using the camera meter to expose remember that the GH5 as most cameras has only three settings for metering: multi area, center weighted and spot those influence how the camera calculates the average exposure, this is true also if you use manual mode the reading on the meter will change depending on the metering mode. However for what we have said here if your objective is simply not to clip highlights you have a long way to go before reaching 90% IRE with HLG.

In short you have three options to set exposure on your GH5:

1. Super lazy option trust your camera meter as this was a still image, most likely you will be exposing to the right and without further checks there is a chance to have dark area or clipped highlights.

2. Use Zebra and manual exposure in combination with the camera meter to ensure you stay within safe limits.

3. Use waveform monitor and completely ignore the other parameters as this gives you full control of what you are shooting and removes any dependency on having or not an HDR monitor

As a final note it is important to remember that performing a white balance adjustment is essential in order to expose correctly it is not just to get the colour right as the IRE values on what is white actually change and the camera makes assumptions on what is white to calculate the rest. This is especially true for environment in difficult light conditions.

Getting yourself familiar with waveform monitoring is essential for editing as majority of people will not have the possibility to grade on an HDR screen. In the next post I will explain how to get the lowest possible cost HDR screen that supports HLG.

 

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Panasonic GH5 the gateway to 4K HDR Video

It has been a while I have been busy with some personal stuff and to be frank not much has been happening the Underwater Video or Still scene that was of interest to me until pretty much September 2017 when Panasonic released the 2.0 version of the DC-GH5 firmware.

The link to the firmware updates is here and here is link to the full PDF

The section we are interested is this one

4K HDR video recording

– [HLG] (Hybrid Log Gamma) is added to [Photo Style]. HDR (High Dynamic Range) is a mode to reproduce both bright part and dark part in an image, making it look just as human eyes see. The camera records video with a designated gamma curve compatible with ITU-R BT.2100, and you can now choose Hybrid Log Gamma (HLG) in [Photo Style].
– A low-bit-rate recording mode 4K HEVC for HLG was added. This enables playback on AV equipment compatible with the HEVC compression format, such as Panasonic 4K HDR TVs.

 

In the PDF we read this additional information

Recording of HDR (High Dynamic Range) motion pictures in HLG (Hybrid Log Gamma) format is now supported. With this format, you can record bright images susceptible to overexposure with more natural colors than is possible with conventional formats.
• “HLG” is a standardized HDR video format that converts and expands the dynamic range of

compressed high-luminance image data on a supported device.
• The monitor and viewfinder of the camera are not capable of displaying images in HLG format. • HDR images appear darker on devices that do not support the HLG format.

If you have headache to understand what is HLG and how it differs from other HDR formats search on the internet the following short document from BBC may help.

 

Why does HDR matter and what can I do to record HDR?

HDR matters because the human eye is more sensible to contrast and colours than resolution. In majority of cases if you do a blind test of UHD 4K footage to anyone sitting at the recommended seating distance for cinema at home (look up SMPTE seating distance) nobody can actually see differences between HD and UHD and this is because the ability of the human eye to resolve pixels is limited by our visual acuity. So why does a YouTube video in 4K looks better than HD? Simply because the bitrate is higher and this means the quality is higher but if you look at your own 4K footage at home and scale it down to HD with good quality you are not able to tell the difference.

However try now some HDR material if you have Amazon or Netflix or even on YouTube and have a compatible Tv set the difference to normal content is staggering. This is because a normal REC709 (the standard for HDTV) display has 6 stops of dynamic range. There are no official figures of how many stops is REC2020 for HDR but good Tv sets are capable of around 10 stops. Now that is a big difference especially on the bright part of the image which is where the HDR displays really excel.

So HDR does matter more than 4K UHD in fact Sony has just produced an HD set HDR capable not sure there will be many of those but this gives an idea.

So how do I record HDR and why there are no HDR certified cameras but only certified displays? The answer is pretty easy you need a camera that offers more than 10 stops dynamic range in video and that is where our Panasonic DC-GH5 comes into the picture.

The camera is capable of 13 stops dynamic range but what is more important it can produce around 8 eV even at ISO 12800 so in essence the camera is well above what is required for REC709 and it can get to around ISO 3200 and still produce nearly 10 stops which is great. So if you have a Panasonic GH5 you have a sensor that is capable of producing the required dynamic range.

However this is not sufficient the camera needs to be able to product at least 10 bit colour depth, an image resolution of 3840×2160 and a colour palette aligned to BT.2020 specifications (wide colour gamut) and finally have the appropriate transfer function to deliver the signal. Majority of commercial cameras are not capable to deliver 10 bit colour depth and do not have a compatible transfer function. The GH4 predecessor of the GH5 was already capable of delivering 10 bit colour to an external recorder using the HDMI output now the GH5 makes this available in camera for recording on SD card at bit rate of 150 mbps IPB and 400 mbps all intra H.264.

HLG vs VLOG and why it matters

Before the firmware 2.0 the only way to produce HDR out of the GH5 was to buy the VLOG upgrade and then attempt to use the recording feature of the camera or an external recorder with Prores 422 or 422 HQ and then take a trip into grading. The reality is that once you crammed the VLOG dynamic range into a REC709 format you essentially limit yourself to 6 stops and therefore waste majority of your effort. So in order to extract real dynamic range you need to output in HDR that is possible but not so easy to do. In practical terms unless you are producing a documentary you will soon give up using vlog underwater because it is just too much work. Here now comes HLG so what is good about HLG and why this can make a real difference here my list:

  1. It is free you don’t need to pay for an upgrade
  2. It is backward compatible with standard dynamic range
  3. Requires a less intensive workflow compared to Vlog
  4. You can produce a decent file recording in camera without external recorders
  5. If you do have an HDR capable external recorder than it shows things are they are and not the washed out version of vlog

This is just my personal list of reasons there may be more.

How to set the Panasonic GH5 to record in HLG and UHD

There are 3 settings that give you the possibility to record HLG HDR compatible files, two are available in MP4 (LPCM) and MOV and one in MP4 (HEVC).

MP4 (LPCM) and MOV

P1040940
400 mbps ALL Intra
P1040941
150 Mbps LongGOP

There are not many cards that can work at 400 mbps and they are expensive. In any case do not assume that 400 mbps ALL-intra is better than longGOP as longGOP is fairly efficient and if you look into the various YouTube videos you will see it is very hard to see any difference unless you do pixel peeping.

MP4 (HEVC)

There is also a convenient low bit rate format available that uses HEVC in camera you can access it selecting MP4 (HEVC) in the REC FORMAT menu

P1040942

You then have this option available

P1040943

Tests show that when done real time HEVC produces files 50% of H.264 so the bitrate makes sense however unless you want to play the files directly on your Tv this is not such a good choice as the files are too hard to edit with any computer as there are no H265 hardware accelerated display widely available.

So the format of choice is as follows:

REC FORMAT: MP4 (LPCM)

REC QUALITY 422/10 bit/LongGOP 150 mbps

Please note the format at 50/60p does not give HLG in camera only the HDMI output is HLG compatible this is because the output is 10 bit as required by HLG. 8 bit colour does NOT qualify for UHD HDR so if you use this format in camera the HLG photo style will be greyed out.

How to convert 150 mbps HLG LongGOP files

At time of writing only programs like VLC play the H264 10 bit files produced by the GH5 and on my computer they play badly. So when you will go and edit those files your NLE program will most likely convert them into a format that is easier to digest and still supports 422 10 bit colour, this format is Apple Prores.

Unfortunately unless you have a paid software the files will only be unreadable if you use DaVinci Resolve or iMovie. However you can use a command line encoder like ffmpeg and convert all those files for free.

The command once you have the executable and you have the files in the right directory is something like this:

ffmpeg -i GH5file.mp4  -c:v prores -c:a copy GH5file.mov

This tells ffmpeg to transcode the video to prores 422 and to just copy the file as is (prores uses linear PCM for audio) here you notice that the source file has mp4 and the destination mov that is the default for prores and the reason to set your GH5 to record mp4 and not mov.

I have developed an automator script that is able to convert all selected files in the memory card and place them in a location of choice on the hard disk or else.

automator

Ffmpeg will convert using prores 422 that in my case bumped the files from 150mps to 474 mbps as prores is an all intra codec this is reasonable and there is no reason to use higher version like 422 HQ starting from a 150 mbps longGOP. Obviously if you use an external recorder feel free to use the higher bitrate available.

How to produce your HDR video clip for free

DaVinci Resolve is able to use your prores files converted from the GH5 and produce HDR compatible files.

You need to go into project settings and select colour management and change your settings as shown here

DaVinciProjectSettings

Colour Space Rec.2020 and Gamma Rec.2100 HLG will produce a file that on a compatible Tv will trigger HDR.

Now the bad news if you don’t have an HDR monitor it is very hard to grade properly on a standard monitor although you can look at luminance curves and chroma curves to see if you have situation of bad exposure or saturation this can be tricky with underwater footage so the trick is to try and get it right in camera.

Of particular interest is the HLG View Assist setting on the GH5: as the screen of the camera is not HDR this should help exposing the scene properly but I have to yet determine what is the setting that I prefer.

Well that is all for now…!

 

4K with the Sony RX100 in Egypt

 

 

It was time to go for a second trip with the RX100 Mark IV

I decided last minute to use the UWL-H100 LD however I managed to forget the M67-LD converter so ended up taking footage holding the wet lens with my left hand.

This created some flare issues in some scenes anyway judge for yourself.

I used the Picture Profile PP6 modified with some small changes around color matrix (I used the Pro setting) and some increased saturation.

As always the RX100 cannot white balance underwater so I used a filter (deeproof), this gives a magenta tinge and sometime the water looked a bit purple.
I have two versions of this clip the first one uncorrected and the second where I tried to remove the purple water. Look for yourself which one is best.

First version with minimal to no editing is here

 

The second version has some colour correction mostly to remove the cast but I have also done some minimal correction in some scenes at the surface shot without filter.

The other settings were shutter speed 1/50 fixed, Auto ISO with max ISO set to 800, auto white balance.

Generally I am very happy with the RX100 however the snorkeling footage was affected by one episode of fogging of the glass port. This was during a dolphin trip so very disappointing. The camera got extremely hot and I think the fact I was holding my hand close to the port to hold the wetlens created the problem as this had never occurred before.

Upon reflection I think I will go back to the UWL-100 M67 type two as the colours I get with the magic filter were superior in my opinion and more natural.

For those wondering about the dugong dugong it was dark as I was free-diving to 12 meters with the camera and the wet lens hand held so not the easiest job.

Let me know which version of the video you prefer!

Getting the best underwater colours for your 4K Sony RX100 Mark IV

It is not a mystery that even the new Mark IV version has issues with custom white balance.

The ergonomics have not changed and you need to go into photo mode to set custom white balance but generally underwater results are poor. Using filters is therefore a necessity also on the new 4K version.

RX100 Mark IV Video Behavior

The RX100 offers now a 4K 100 mbps mode and can use picture profiles.

I have used a modified version of PP6 that use the cine2 gamma curve, I have however changed the colour to the Pro mode and changed a number of other settings in my last video in Puerto Galera.

The water was green and murky but this gives you an idea of what you can get.

Filter Options and Wide Angle

Although the Nauticam WWL-1 is the best lens for the RX100 it does not take filters and therefore is not adequate for video.

In this review clip you can see the options available on the market.

In terms of wide angle you have two options for 4K:

  1. Inon UWL-H100
  2. Inon UWL-100

Both lenses work fine in 4K however the older UWL-100 achromat does vignette in photo mode.

The UWL-H100 offers a very wide field of view also in HD mode with no vignette and accepts the mangrove/deeproof filter.

This filters is loaded with magenta so I suggest adjusting the tint in the auto white balance mode to +2 green.

The UWL-100 works fine in 4K and is wider than the UWL-H100 however has only the M67 mount. If you have one of those lenses you can use the Ikelite 6442 filter. This filter required you to remove the rubber ring on the lens and does work quite well except has a yellow cast to it you can reduce by changing the tint to +2 blue and increasing also magenta to +1.

For flexibility purposes probably the UWL-H100 is better as it takes the bayonet but the UWL-100 is really wide and has a little less fringing. Some people do like the UR/PRO filters better.

I hope you find this post useful and good luck with getting the best colours from your Sony RX100 Mark IV

What does UHD Premium specification mean to 4K

The UHD alliance is a working group that includes a number of well known brands.

In the board are directors of the following major players:

  • Fox
  • Sony
  • Netflix
  • Panasonic
  • Dolby
  • Technicolor
  • Samsung
  • LG
  • Universal
  • Warner Bros
  • Walt Disney
  • Direct Tv

The members include companies like Sky, Amazon, Intel, Thx, Dts and others.

The key purpose is specifications mostly for high end use and the key pillars are:

  • High dynamic range video (SMPTE ST2084 EOTF)
  • Wide colour gamut (BT.2020)
  • 4K resolution
  •  10 bit colour depth

This is obviously a large improvement compared to the current specification of HD Video:

  • BT.709 colour
  • 1920×1080 Resolution
  • 8 bit colour

Probably the most interesting feature is high dynamic range video as the human eye is more sensitive to contrast than it is to colour and resolution although surely the 10bit colour depth will make a difference.

Currently all professional recorders that manage 4K use 10 bit colour but none uses the BT.2020 colour gamut and the dynamic range is left to the sensor quality and has no minimum specifications.

So what will UHD premium mean to us? Well currently not much!

The key is that UHD alliance has also stayed clear from the major issue for distribution that are the video codecs.

Currently HEVC or H.265 has got royalty challenges but is the most  efficient codec on the market and the widest in terms of diffusion in hardware.

To give an idea two minutes of 100 Mbps H.264 become 76.5 Mbps once you push the H.264 to the limit but the corresponding H.265 is only 13.6 Mbps only 18% of the size.

Google does not support HEVC and are distributing 4K using VP9 and H.264. From my tests VP9 is not as efficient as HEVC the same file came at 17 Mbps. The key issue of VP9 is playback that does not even work on a powerful home computer although some new Android TV have accelerated VP9 and so has the new Nvidia box.

Whilst this gets worked out it is likely that cameras will continue to record in H.264 and the key here is higher bitrate as H.264 is clearly inefficient with 4K.

If you are in the 4K space and you want to produce semipro or pro footage you need to have an external recorder working in Prores HQ or your device needs to be able to record higher than 100 Mbps.

Sony has just introduced the XQD memory cards that write 800 Mbps

http://pro.sony.com/bbsc/ssr/mkt-recmedia/mkt-recmediaxqd/product-QDM128/

This is potentially a way forward for higher bitrate recording as UHS 3 is limited to 240 Mbps and would only work with compressed footage.

Another thing to consider is that you need a pretty big Tv to notice UHD at the normal viewing distances we tend to watch.

http://s3.carltonbale.com/resolution_chart.html

Carlton Bale was on the scene few years ago when HD came about and the conclusion was you need 55″ or more at 8 feet to ‘see’ HD as your eyes can’t resolve more.

This distance becomes 120″ at 8 feet which is essentially the size of a projector screen.

Essentially UHD seems to be more for computer freaks watching clips very close to the screen that for the average user.

I did several test on my Tv with clips I had produced in 4K downscaled to HD and at my normal viewing distance I could not see any difference what so ever!

Essentially I have determined that 50 Mbps XAVC from the RX100 Mark IV looks actually better than 4K on my Tv.

I guess we will have to wait for HDR to see some real benefits meanwhile the clips from you tube look better simply because they have more information. There is a factor of 6x for UHD compared to HD and this shows a higher quality clip.

I don’t see a large future for UHD in TV broadcast it could die as 3D just did.

 

The painful quest of 4K Video

2015 has probably been the first year where consumer devices have taken the journey to 4K as even iPhones now can record at Ultra High Definition.

However there is still a very long way to get us to the level of standardisation of HD video and the war of the codecs has still to determine a winner.

As of January 2016 if we consider only digital cameras only three manufacturers produce 4K capable devices that can be housed for underwater use and those are Canon, Sony and Panasonic.

Specifically we have two compact cameras with fixed lenses, the Sony RX100 Mark IV and the Panasonic LX100, two micro four thirds the Panasonic GH4 and GX8 and three DSLR the Sony A7IIR and A7IIS and the Canon EOS-1D C that was in fact the first camera to record 4K video in 2013.

From a consumer point of view we are interested in a 4K device that can operate with wet lenses across the focal range and that is under the $5,000 mark including the housing so I will focus on the Micro Four Thirds and fixed lens compacts and exclude immediately the Panasonic LX100 that requires a port system to operate we are now left with 3 devices that today are the real options for 4K underwater video.

4K Digital Cameras for Underwater Use

  1. Panasonic GH4 with Panasonic 14-42mm II Mega OIS
  2. Panasonic GX8 with Panasonic 12-32mm Mega OIS
  3. Sony RX100 Mark IV

I have added the lenses of choice of each camera for convenience.

In 35mm terms the focal lengths offered by the 3 devices are:

Panasonic GH4 with 14-42mm : 35-105mm

Panasonic GX8 with 12-32mm: 31.2-83.2mm

Sony RX100 IV: 28-80mm

Wet lenses

Both Panasonic cameras revert to a traditional 35mm cameras when the 4K crop is applied. The wet lens of choice is therefore the old Inon UWL-100 with M67 thread. This is a lens with a magnification of 0.57077 that with the 14-42mm II Mega OIS and Macro Port 35 or the 12-32mm and Macro Port 29 performs very well without vignetting and offers zoom through the whole focal range. The same lens appears to work fine also with the Sony RX100 Mark IV but is almost border line in terms of vignetting and I will need to conduct further experiments for now we will refer to the Inon UWL-H100

Focal range with Inon UWL-100 / UWL-H100* (Sony)

Panasonic GH4+14-42 : 20-60mm

Panasonic GX8+12-32 : 18-48mm

Sony RX100 Mark IV : 17-48mm

You can see that the GX8 and the RX100 are virtually equivalent and the same holds true for macro with the GX8 and the RX100 offering same working distance and magnification. The GH4 is superior in this area due to the longer focal length after crop of 105mm. For me the most versatile wet lenses for macro remain the Inon UCL-165 despite the various Nauticam and Subsee options because you can cover all the working distances from 16cm to 8cm which is the sweet spot for macro work.

Unfortunately the level of magnification obtainable with the GX8 and RX100 is not great and really small subject will still look tiny in the frame. Obviously the use of the 14-42mm lens on the GX8 resolves all problems except the field of view with wet lens at wide end is now 21mm anyway not a huge issue.

I am still waiting for a proper review of the GX8 but in terms of 4K resolution I have been impressed with the Sony RX100 Mark IV that appears to be sharper than the GH4 and even the A7IIR.

4K formats

In terms of 4K recording all devices on the market use some form of H264 100 Mb/s codec Sony uses what they call XAVC S while Panasonic uses a standard Mp4 compatible wrapper. Sony codecs do not use B frames in their H264 implementation but this does not seem to affect quality that much.

So now that you have your 4K footage what do you do with it?

The first consideration is that all cameras record internally at 8 bit with 4:2:0 subsampling this means that colours are only recorded for 50% of the pixels and then interpolated. The implication is that color grading opporunites are limited and heavy manipulation should be avoided to avoid undesired effects such as banding.

This means custom white balance better with a filter is still very much needed for 4K.

In the Mac camp there are many consumer options for 4K editing including iMovie, Final Cut Pro X, Adobe Premiere Pro and for Windows you also add Sony Vegas, Avid composer and many more

S-logs or V-log are also not meaningful at 8 bits without external recording capabilities as grading will ruin the footage.

Workflow for Consumer Use on Mac

For the average home user on a Mac iMovie offers now decent functionality and imports and edits in native format all the clips produced by our selected cameras. iMovie also exports in Prores 422 which is ideal for storing your master copy after editing.

Unless you edit on a laptop or a machine with poor hardware there is no need to convert the footage in intermediate formats as most of GPU have H264 acceleration so your 4K workflow will look like this:

  1. Import into your 4k editor
  2. cut and edit sequence
  3. Perform minimal corrections to exposure and color
  4. Add some transitions
  5. Add music of voice over
  6. Export to Prores 422 or 422 HQ if available
  7. Compress with 3rd party software or plug in

Compression Headaches

Step 6 is particularly important as none of the above mentioned editors has good native export capabilities so you want to do that with another program. If we take for good what apple says Prores HQ is very rarely fooled by 4K footage at 737 Mb/s for 25p. Consindering that our footage was 4:2:0 to start with this means we need only 75% of that bandwidth or 552 Mb/s. As Prores 422 records at 492 Mb/s which is only 11% less than the required bandwidth so iMovie with the Prores export option is pretty good.

We now have our 492 Mb/s video with most likely an AAC audio what are we going to do with it?

This is where it gets really painful. If you have a 4K Tv you definitely want to watch your footage on it, today UHD Tv support the HEVC codec and more recently also the VP9 codec that google uses in YouTube however both those codecs have limited options for encoding and do not have any hardware acceleration support in your computer that will be used to compress the footage.

To make matters worse if you then share your footage online on YouTube this will be heavily re-compressed. I have done some analysis on some clips that I watch to find that 4K bandwidth is between 17 and 20 Mb/s in H264 and the files are not even encoded with CABAC to ensure they can be played on devices with limited hardware capabilities. In terms of web browser many now supports VP9 however hardware acceleration is lacking so it is likely that you will be watching H264 4K footage at 18 Mb/s when you connect to YouTube on your computer.

It is likely that the mp4 files that you can produce with handbrake or other tools are easily coded at 60-70 Mb/s so YouTube, as it does with HD footage, will introduce significant issues to your 4K videos.

Interestingly the 4K bandwidth is higher in terms of Bits/(Pixel*Frame):

  • 0.090 for 4K
  • 0.076 for 2K
  • 0.055 for HD

This would suggest that 4K videos are less compressed but on the other hand the compression is less efficient. 2K appears an interesting mix that still uses Cabac and 3 reference frames but is really a computer only option.

For who has access to an x264 encoder  this is a suggestion for 4K  encoding that does not kill your computer

Preset slower – modified

cabac=1 / ref=5 / deblock=1:0:0 / analyse=0x3:0x113 / me=umh / subme=9 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=2 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-2 / threads=3 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=3 / b_pyramid=2 / b_adapt=2 / b_bias=0 / direct=3 / weightb=1 / open_gop=0 / weightp=2 / keyint=250 / keyint_min=25 / scenecut=40 / intra_refresh=0 / rc_lookahead=60 / rc=crf / mbtree=1 / crf=18.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / ip_ratio=1.40 / aq=1:1.00

The options that differ are ref=5 otherwise we break the limit of level 5.1 and the decoder may have issues, and crf=18 from 23 to increase quality.

This H264 encoding can easily produce files around 1.4 Gb for just 3 minutes and will require playback on the device or USB disk attached or a good cat 5 ethernet network or solid wireless at at least 100 Mb/s effective speed.

It follows that H264 really is not the way forward at 32 Mb/s HEVC two pass or crf=23 in single pass you get files that are 20% or less of the size and work well if you have a 4K HEVC accelerated player like I do. At this bitrate is also very easy to stream over your wireless LAN even at mediocre quality. Unfortunately YouTube will reject your HEVC files and require H264 or VP9.

Google plot for 4K world domination

Google did not want to incur more royalties so they pushed out HEVC to use the open source VP9 as they did years ago with Vp8.

VP9 is at least in the Mac version very slow and seems fairly amateurish. They have been succesful with Android Tvs that have YouTube as a prime source of 4K content because the YouTube app does not work in 4k on Tv sets unless it can decode VP9. This is clearly only a commercial plot as all TVs can play H264 and YouTube wants to reach as many people as possible with 4K therefore keeping bandwidth below 20 Mb/s and accessible to the higher end of DSL connections not just fiber so that they can push their ads to the masses, however it also means that your video will look pretty pathetic on YouTube unless  you use a VP9 capable browser or Tv set or android to box to watch it.

At time of writing the only android box that can decode Vp9 is the Nvidia Shield Tv so if you want to watch YouTube 4K videos at 18 Mb/s Vp9 there is at least one choice.

http://shield.nvidia.com/android-tv

Also the Roku and Kindle fire Tv support YouTube 4K but don’t have Kodi so I would not consider them

 

 

 

 

 

 

 

 

 

 

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

Sony RX100 Mark IV Picture Profile Part 2

I have done some further research on the picture profiles and found out quite a bit of information.

In this post I will focus on the luminance and black gamma.

Luminance

Luminance determines the range of black and white that are in the footage. People familiar with the Panasonic GH4 will know that you can set luminance fundamentally in two ranges: 0-255 and 16-235.

What this means that you have in the first case 256 grades of grey and the in the second 220. Some people confuse luminance with dynamic range but they are not the same thing.

You will somewhere find the definition of limited for 16-235 and full for 0-255 this is what it means.

In particular video broadcasting legal luminance is 16-235 so if you use a clip produced at 0-255 the extremes will be clipped this is anyway resolved as the levels are mediated when clips are produced for compatibility.

On the other hand if you use a clip with range 16-235 on a computer that has 0-255 luminance range it will look as lacking deep blacks or whites.

Ultimately you need to decide what is that you are shooting for and if your clips are going to be played on a computer that works in RGB or on a Tv that has YUV.

Profile Name Description Luminance Range Dynamic Range
PP1 Movie 0-255 < 7 stops
PP2 Still 0-255 < 7 stops
PP3 Video Natural 0-255 7 stops
PP4 Video Vivid 0-255 7 stops
PP5 Cine1 109% 0-255 10 stops
PP6 Cine2 100% 16-235 10 stops
PP7 S-log 0-255 13 stops

So the only profile that is broadcast compatible before editing is PP6 or the Cine2 gamma curve.

You can see that the dynamic range is the same for PP5 and PP6 so the fact that the camera records more grey levels does not really change things as the cine2 curve is smoother so it can accept higher input signals.

Black Gamma

In order to increase depth of blacks it is possible to use the black gamma setting. This has 2 controls, one is the Range Narrow, Medium, Wide and the other is the level that goes from -7 to +7

If you are going to grade your footage of and if you are going to use the video gammas PP1-PP4 you should not touch the black gammas otherwise you risk crushing the blacks.

However if you intend to use the cine profiles straight out of the camera you can tweak the black gammas accordingly.

The range determines where the setting will be effective.

Broadly speaking Narrow works on the first 10% of the signal, medium around 20% and wide around 30-35%.

What it means is that Narrow really works on the deeper blacks as you move to Wide you are altering also the grey and effectively changing the balance of the whole image.

More details here http://helpguide.sony.net/di/pp/v1/en/contents/TP0000909110.html

For what concerns the level a positive value will move black towards grey and a negative value shift grey towards black.

There are two main uses of the black gamma: get deeper blacks without altering the overall contrast this is obtained using the Narrow setting and a value between -3 and -7 or use the Wide setting with negative values to give the whole image a darker tone.

A setting of Wide with level around -3 gives an overall darker tone to a Cinegamma if you don’t want to change the blacks in post and remains overall balanced.

Which leads to my current favorite profile that is a customised PP6 setting the parameters that I have changed are:

I have tested the various Gamma with backlight situation and I found that Cinema2 performs best on my Tv where I watch my clips.

I prefer Cine2 even on the computer to be frank but it is true that the blacks are a bit light.

Color mode: I have tried Cinema and Pro am now on Pro with Saturation +8

Black Gamma: Range Wide Level -7 as the cine2 mode is quite dull I like to push the blacks a little overall.

As the Sony RX100 Mark IV records at 8 bit my opinion is that using S-gamut is not worth without an external recorder. And to be honest the amount of grading possible is quite limited so my approach is to get the video as good as possible out of the camera.

This is a little test with my Kitten

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.

Picture Profiles for the new RX100 and A7 Cameras

The new cameras in the RX100 and A7 series can record 4K video internally but what is more important come with significant enhancements for video shooters.

Probably the most important feature is the availability of picture profiles that have a number of presets that can be further customized by the user.

There are many forums on the internet with custom setting to try to extract cine like look from Panasonic GH4 clips but all in all we can say that the controls in a still camera have been quite limited so far.

The new software that comes with the RX100 and A7 is a real step forward in this respect and contains all characteristics and functionality previously only present on Sony professional and semi professional video cameras.

 

The Seven Presets

The starting point of using a picture profile is to find one that we like as a starting point for further customization; the new Sony cameras have 7 profiles already loaded with example settings. The profiles have many characteristics that can be configured but probably the most important is the shape of the gamma curve because it also determines the minimum ISO and the availability of other features.

Profile Name Description Minimum ISO Knee Mode
PP1 Movie 125 Auto/Manual
PP2 Still 125 Manual Only
PP3 Video Natural 200 Auto/Manual
PP4 Video Vivid 200 Auto/Manual
PP5 Cine1 109% 200 Manual Only
PP6 Cine2 100% 200 Manual Only
PP7 S-log 1600 Manual Only

The descriptions above are my personal short description as the user guide is quite confusing.

Profiles PP1 to PP5 are usable straight from the camera, PP6 is optimized for editing and PP7 can’t be used without editing.

 

Standard Profiles

The profile PP1 and PP2 emulate the camera behavior in movie and still mode in terms of contrast and saturation. The main difference between the two is that the Still mode has stronger contrast and saturation than movie. Both use a minimum ISO of 125 and they allow customization of the standard camera modes.

PP1 Movie
PP1 Movie

Within a profile you have access to controls for color and sharpness at much granular detail that you have with the camera in normal mode. For example the saturation slider goes from -32 to +32 and the sharpness can be completely controlled manually. Colour depth is available in the range -7 to +7 for the whole RGCCYM palette. The customization of those controls lets you have the colours you want off the camera this can be particularly important to people looking for a specific look of certain colors typically red and blue.

PP2 Still
PP2 Still

For a complete description see this link:

http://helpguide.sony.net/di/pp/v1/en/contents/TP0000909111.html

 

Another feature that is incremental to the normal movie mode is the knee setting. The knee is particularly useful with highlights and with back lit shots. What it does it to compress the highlights within the usable signal range.

Knee Point and Slope
Knee Point and Slope

 

 

The knee is a way for those who like video look footage to capture more highlights and avoid hard clipping of back lit images.

 

Video Profiles

The profiles PP3 and PP4 use the ITU709 gamma curve that is the standard for high definition video television. The gamma curve has a low light gain of 4.5 dB and for this reason the minimum ISO is 200.

The video profiles bring substantial increase in  both shadows and highlights to the image compared to the standard profiles.

PP3 ITU709
PP3 Video Natural

The difference between those two profiles is the selection of the color mode. The PP3 profile has a Pro colour mode that the manual says ‘it is similar to professional Sony broadcast cameras’ the PP4 instead has an ITU709 Matrix colour mode.

PP4 Video Vivid
PP4 Video Vivid

What it means is that the Pro colour is slightly below the standard saturation whilst the ITU709 Matrix is extremely saturated looking like the Tv program that go these days. Both settings allow usage of the knee setting in auto and manual mode. The idea is to restore the highlights and make the footage look less harsh. The issue is of course that this has only effect on the highlights and not on the shadows.

 

Cine Profiles

The profiles PP5 and PP6 use the two different Cine gamma curves one is limited at 109% and the other at 100%.

Gamma curves
Gamma curves

Those are the official descriptions:

Cine1: Softens the contrast in darker image areas and emphasizes gradation changes in lighter image areas, producing a subdued tone overall (equivalent to HG4609G33). Gamma curve that obtains a dynamic range of 460% when the exposure is adjusted to 33% video output with 18% reflectance gray. The maximum value of video output is 109%.

Images shot with this gamma can be used without grading, but since the images have smooth gradation characteristics, this can be used to grade and finalize the viewed image in the post-production process.

PP5 Cine1
PP5 Cine1 109%

Cine 2: Similar results to [Cine1] but optimized for editing with up to 100% video signal (equivalent to HG4600G30). Gamma curve that obtains a dynamic range of 460% when the exposure is adjusted to 30% video output with 18% reflectance gray. The maximum value of video output is 100%.

PP2 Cine2 100%
PP2 Cine2 100%

Both curves are cine like and therefore do not use the knee function by default this is because a cine gamma curve is already clipping at much higher signal levels. The Cine2 curve has less contrast than Cine1 and is limited to 100% as opposed to the standard 109% so it is optimized for editing and the footage will lack whites and look fairly grey.

Practically the cine profile achieve a higher dynamic range using a smoother curve, this compares to the video profiles where the curve is pretty much the same until the highlights get compressed using the knee function.

S-log2

The PP7 profile is for S-log2, this has the highest dynamic range but the minimum ISO is 1600, the footage looks really bland out of the camera but this can be really enhanced through editing to bring out all the details.

PP7 s-log2
PP7 s-log2

 

My Take on the Picture Profiles
I think the whole cinema like video is a very overrated subject for underwater use. An acid test to understand where you stand is your own TV. If you use the picture settings Vivid or Standard then you are a video like person, waste no time pursuing cinema like look as in the editing you will effectively bring it back and eliminate all the detail you capture by increasing contrast and saturation.

If instead your TV is set to Cinema or is even calibrated then you are a Cine like person.

Personally I think S-log2 for underwater use at 100 mbps is a total waste of time and it is only worth with external recorders. The bitrate is too low to capture that amount of detail and resist extensive grading and actually shooting at 1600 is pretty difficult and requires ND filters (that the RX100 has) to perform decently.

You can take still shots with the picture profile so the first thing to do is to take a few pictures and see what image you like the most, then you can start tweaking.

I found myself to like the cine settings in terms of contrast but I find then too bland in color so I have settled for +20 saturation right now.

Between Cine1 and Cine2 is quite difficult to choose because although Cine2 is in theory optimized for editing actually it looks pretty good straight from the camera for my liking. I particularly like the fact that the highlights almost never clip with this setting even in harsh conditions. It is possible to mix the Cine profiles with the Pro color mode but I found that using saturation was giving the same result.

PP5 Saturation +20
PP5 Saturation +20
PP6 Saturation +20
PP6 Saturation +20

 

Detail setting (aka Sharpness)

The last feature of the RX100 and A7 new controls is the fine tuning of the sharpness setting. I find that the default works pretty well except at high ISO where you want to start adjusting slightly the behavior.

The full guide is here http://helpguide.sony.net/di/pp/v1/en/contents/TP0000909112.html

But it takes a bit of time to understand the settings.

The starting point for me is the crispening setting that in perfect Sony tradition means exactly the opposite of what you would think. So a setting of +7 means actually limit the sharpening on speckles and noise where a clear shape can’t be detected. Once you set crispening to the max and you shoot at high ISO you see how it reduces the noise. However the issue is that now the sharpness has also reduced so in order to restore the effect you go back to the total level of detail and set it to 7. Once you do that you find out that now the sharpening applied correctly is actually excessive so the limit setting effectively clips the amount of sharpening applied to the edges I use this at 3, as this results in a reduction of highlights sharpening (glass reflecting objects look dull) I then set the highlight detail to +2. After I did all of that the end result was very similar to the standard setting and a bit softer on the edges, practically it was only better at very high ISO so I went back to the original setting.

 

 

Tip & Tricks for Compact Cameras Users