Is the GH6 worth the upgrade?

After a few months of using the GH6 is time to answer the question pretty much every GH5 user is asking now.

The answer as always is … it depends. I hope this article will help you clarify your thinking.

Noise Performance

I have done a number of tests on all the GH5 and GH6 series cameras including the original GH5, the GH5S, the GH5M2 and the GH6.

While many people talk about dynamic range most only care about noise and in particular if this will show in your footage or not.

Unfortunately read noise accurate calculation are only possible for RAW image files not video. Video has an additional issue which is temporal noise.

As noise is random by nature each frame will have its own noise and the changes in noise generate that flickering effect that everybody hates. This is called temporal noise and to an extent every camera has it.

Obviously if you have less noise you will see less flickering but all cameras will have some.

The other discussion that has been going on forever is that large pixels are better for low noise, this is also not true as more pixels can be added and noise averaged out. So the only thing that matters is sensor size, sensor construction and the sensor coating.

The original GH5 did not have a great coating so when the GH5M2 was released sharing the same coating of the G9 most people were saying well it won’t matter much while instead it does.

The benefit that the AR coating brings to the GH5M2 compared to the original GH5 is around 2/3 Stops which is not negligible.

VLOG Implementation

The other difference among the various GH cameras is how VLOG is implemented.

In the GH5/GH5M2 VLOG is simply a curve and achieves no major benefit compared to other photo styles but it avoids you clipping highlights at expense of additional noise. This noise is managed overexposing 1 stop.

In the GH5s/GH6 VLOG applies underexposure behind the scenes of 1 and 1 1/3 stops so dynamic range is maximized. Both cameras have strategy to deal with noise. The GH5S applies noise filtering the GH6 scaling the net result is that VLOG in those camera is better than shooting something else.

Analysis

Using a mix of read noise on RAW files and calculation of how noise is managed I have created the following chart that shows how noise goes at bit level when ISO goes up.

Here you can see all the cameras I think this graphic explains pretty much what happens at high ISO. For low ISO you need to take into account shot noise and my analysis is not able to evaluate that however this will make a small difference to the evaluations.

So lets go into the specifics

I am a hybrid user I want the best of both worlds which camera is better for me?

The GH5M2 is currently the best camera in this category, it offers the best still image performance, it has IBIS and video is very good and can be improved with an external recorder if you wish. It also records 8 bits which is fine for those who do not want 10 bits at all costs and uses SD cards. The dynamic range of a still image is the best of all GH series cameras as seen on photonstophotos. Remember that RAW files are not denoised or scaled like video.

I am a GH5 video user should I buy a GH6

Assuming that you shoot vlog because if you don’t any camera works just fine the answer is yes unless you are always at ISO 400 with your GH5 and do not want to buy more ND filter the GH6 is a significant step forward.

You need to evaluate however if you need all the GH6 offers.

I am a GH5S video user is the GH6 for me?

While the GH6 performance is better than the GH5S in the high ISO zone at low ISO is worse. The GH6 has IBIS and all the features the GH5S has however it is limited to 12800. The GH6 also produces 25 megapixels photos but as a GH5S user this was probably not important.

So the answer is yes if you don’t need really high ISO (>12800).

I am a GH5M2 video user is the GH6 for me?

If you don’t mind ND filters, use the camera in both daylight and low light and you need any of the features like 120fps 4k then the answer is yes.

Conclusion

The GH5 has been a very competitive camera and the GH5M2 further improved on it. The GH5S has its own niche and all of those are strong proposition. When looking at the GH6 the key criteria is that you are focused on video and that you need all the codecs and feature the camera has.

I think this video sums it up nicely

Panasonic GH6 Video and Still Performance

I have had the GH6 now for a bit more than one Month and it is time to get to conclusions in terms of the image quality in both photo and video.

In order to do that I have ran the GH6 side by side with the GH5M2 so far in my opinion the best hybrid Micro Four Thirds camera.

Video Performance

There have been a number of reviews online with regards to the GH6 video mode and for me two have stood out.

The first is the review from CineD and the second is from CVP

You do need to take into account a combination of factors when you look at video because the functionality and the camera image pipeline are what makes the video.

In general terms when it comes to functionality and codecs offered the GH6 is simply incredible. I have taken the opportunity to start bird video project and that would have not been possible with the GH5M2 or any previous GH series camera.

You can follow my work as it develops here

My latest land wildlife project is about Grey Heron nesting

For the first time I am shooting in VLOG an entire project and this is due to the implementation in the GH6.

VLOG Implementation

In the GH6 the implementation of VLOG is similar to what is done in the GH5s and the S series. So when you shoot in VLOG the camera is applying a negative adjustment of 1 1/3 stops behind the scenes.

This means when you are shooting at the 250 base ISO the camera is actually internally working at ISO 100.

In addition the GH6 no longer underexposed middle grey behind the scenes and it is spot on the grey card and in the RAW linear data.

In addition we now have a Dynamic Range Boost functionality that blends two frames one at High Gain and one at Low Gain to give you additional headroom in the highlights.

The result is that when you look at VLOG you have increased performance with dynamic range boost on from ISO 2000 and very strong dynamic range up to ISO 6400.

I have run some read noise tests using my astrophotography software and then applying the exposure shifts I come with the above result. Take into account that dynamic range in the GH5M2 is clipped on the highlights at 1 stop less so in reality although the graph seems to indicate that the GH5M2 at ISO 400 has more dynamic range this is not actually the case. However that is true is that up to ISO 1600 when the GH6 has dynamic range boost OFF the GH5M2 outperforms the GH6 in video.

I have shot side by side video and I will post on my YouTube channel some time soon.

However the first conclusion is:

if you do not need 4k120fps or 5.7k and don’t exceed ISO 1600 the GH5M2 is a better choice

What does this actually mean and how low light can you go? In practical terms f/2 1/60 ISO 1600 means 17 lux middle grey typical of floodlight buildings exteriors so not that dark but not that bright either. An indoor lounge with decent lights will have this level of illumination. Of course you can put a strong ND filter on the GH6 and enjoy more dynamic range however this has a number of other side effects.

The second conclusion is

Using dynamic range boost gives you 1 1/3 stops improvement on the GH5M2 from ISO 2000 and more highlight headroom but worse noise performance at low ISO

So what is the use case that will definitely favour the GH6? Typically need for high quality high frame rate formats and decent low light performance. The camera does pretty well up to ISO 6400 in VLOG.

If you don’t use VLOG there is noise reduction in camera so although it looks clean the details is not anymore there. So personally I would use VLOG when possible with the GH6.

Photographic Performance

When it comes to photos the design choices of the GH6 backfire. The camera has incredibly high levels of read noise as per this graphic.

Read Noise vs ISO

In addition the read noise is higher in the low ISO before it turns to ISO 800 when dual gain output is in action.

This has of course a direct impact on the theoretical maximum dynamic range.

Maximum Dynamic Range

Here you can see that at values up to ISO 640 the GH5M2 really has an edge and the improvement of the GH6 is really limited to the region between 800 and 3200 the benefit is modest at best 0.5 stops.

So the third conclusion is:

If you are interested in the best photographic dynamic range in micro four thirds the GH5M2 (and the G9) are better choices

As an example those two images shot outdoor show that in effect our eyes do not really see read noise in a bright scene and once scaled the two camera cannot be taken apart. However if you had shot a long exposure at low ISO you will see grain with the GH6 under ISO 800.

For how hard I try I could not tell the difference between the two images above once processed and scaled.

Final disclosure all my figures look at pixel level noise and dynamic range. Scaling to a common size as shown by the image above will benefit the GH6 more as it has higher resolution but the difference is no so large that the data above is not valid so in general all I said above holds.

I have provided test files to Bill Claff of PhotonstoPhotos and he will publish more reliable and scientific results in due course.

We are both puzzled by the GH6 design and are waiting for another raw converter support to reconfirm however the triangulation of my data with other sources holds so I am quite confident of what I wrote here.

Matching GH5M2 and GH6

Today I went out with both the GH5M2 and GH6 to shoot some roll for my new project.

I have tested the GH6 in my light box and surprisingly CineD2 has changed it is now correct but also more saturated. So to avoid issues I shot both cameras in V-Log. Most readers know I am not a fan of log footage however today they conditions were pretty decent so I was at base ISO and I did not mind closing the aperture as I was shooting birds and landscape.

Lumix GH5M2 set up

I shot the GH5M2 in default settings in VLOG without manipulating exposure. The camera has a tendency to overexpose and I let it do it.

I set up color temperature to daylight to avoid differences and shot All Intra 30fps at 400mbps on a tripod. It was windy at times.

Shot sunrise then the pond that is the target for my long lens work.

Lumix GH6 set up

I used the same settings of the GH5M2 but shot at 60 and 120 fps using the new codecs of the GH6. I did not use dynamic range boost.

As I used a very long lens I had set up a plate for the tripod but I still got occasional shake as I was fidgeting the remote shutter.

As the camera has a lag to start recording I ended up shooting many blanks. I realised the lens is far too long for birds in flight but good for detail shots.

Putting it together

I combined footage in Final Cut Pro and used the standard VLOG to V709 LUT. I then added vibrancy and sharpness.

Each scene was corrected for exposure individually not pre-cooked LUTs were used.

This is the resulting video

I used slow motion from the GH6 at 50% and 25% speed this is really a great feature for wildlife. The only thing missing is a pre-roll

All in call the cameras when the GH6 has dynamic range boost off look very similar and this is because GH6 levels are clipped.

Let me know what you think

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.

Panasonic GH5S Review – Conclusion

I hope you found the tests useful and I guess the key question is:

Is the GH5S still worth it in 2022?

I have prepared a comparison table with the GH5 and GH5M2 using data available and for noise my subjective measurements supported by the video evidence.

As you can see from the table the GH5S still has some unique features:

  • RAW support (ProRes RAW and BRAW)
  • VLOG performance
  • High ISO performance straight out of camera
  • Slightly lighter and better battery life

So if any of the above are essential to you there is still a case for the GH5S.

However the GH5M2 with Neat Video will cost you $1,699+$129=$1,828, for sure you will have to work without Vlog and RAW but you will have many other benefits and you will not need a recorder to shoot 50/60 fps bringing the overall cost down significantly.

Panasonic GH5S long overdue review – Part III Low light Field Test

For part 3 of my test I ran the GH5S side by side with GH5M2 with the same settings used for daylight. The GH5S used VLOG which is the best photo style for it while the GH5M2 used CineD2, again the best photo style for it. Bear in mind if you had run this comparison with both cameras on VLOG the GH5S would have trashed the GH5M2 at high ISO because the implementation of VLOG in the GH5M2 is simply not performing.

The two cameras were set in multi metering with focus at hyperfocal distance. I tried to match the field of view using the 10-25mm on the GH5M2, make no mistake the PL 15/1.7 I used on the GH5S is an amazing and very sharp lens. Both cameras were set to auto white balance and I put the GH5M2 in auto ISO because it shows on screen the value it is using while the GH5S was set in complete manual. Whenever the GH5S was displaying a negative value on the meter I would increase ISO 1/3 Ev. The GH5M2 was left to deal with it in auto as I had previously confirmed the meters were aligned, or at least this is what I thought until this test.

GH5S left and GH5M2 right

I started all the way from ISO 200 and waited until night fall.

If you want to watch the video and form your own view here is the link. You will need a Tv with zoom function to be able to see the fine details.

My expectation was that the cameras would perform almost the same until ISO 1600 at that point the dual gain of the GH5S should produce better results. I will spare the analysis at lower ISO values as it does not really say much.

Analysis

As explained in the video you need to focus on three part of the image. The top part and any residual tone of the sky tells you if the camera is loosing DR. The tables at the bottom are a sign of loss of detail due to noise but also of possible temporal noise reduction. Temporal noise is a flickering resulting from noise scattered differently in the frames. When the image retains detail but has this flicker it is said to have temporal noise. If the clip looks stable but lacking a bit of edge details it is a sign of potential temporal noise reduction in camera.

Due to the lower pixel count temporal noise reduction in the GH5S would perform better than in a higher pixel count camera.

ISO 1250

Here the GH5S is in low gain and my expectation was performance to be very similar. At this ISO value the GH5S retained good detail however showed more noise in each part of the frame.

GH5M2 Moving Detail
Same detail on the GH5S note the added chroma noise

The noise levels appear identical in the static parts of the frame.

GH5M2 static detail

All in all at ISO 1250 the situation appears very similar the GH5S has a bit more noise but still have detail compared to the GH5M2.

ISO 2000

The light dropped suddenly so I did not manage to record the ISO 1600 step on both camera at the same time as I was distracted by external factors (had to order at the bar).

GH5M2 detail at ISO 2000
GH5S ISO 2000

Although the noise appear similar I would say the GH5S retained more detail at ISO 2000, consider the observation is far away and on the edges of the frame so it is a difficult scenario.

GH5MS static detail
GH5S static detail

Looking at the static part gives a different picture with the GH5M2 having an edge and the GH5S smudging details.

ISO 2500

I was expecting the GH5S to be a clear winner at its second native ISO.

GH5M2 detail birds moving
GH5S detail

The part of the frame with motion did not show a much better detail for the GH5S while the static part looked cleaner.

GH5M2 static detail
GH5S static detail

This behaviour makes me think that the GH5S has a stronger temporal noise reduction filter. When it does not detect motion it goes down hard resulting in a very clean image. When it does detect movement it becomes more cautious especially if the moving parts use only a small area. This would explain the mixed behaviour in the ISO 2500 situation.

Overall I was expecting much better performance and a clear difference between the two.

ISO 3200

My expectation was that as the ISO was going up the gap between the two cameras would have increased however at ISO 3200 I was surprised to see the GH5M2 made a recovery and the quality is almost identical.

GH5M2 ISO 3200 motion detail
GH5S motion detail

In addition I can see the GH5S noise reduction starting to eliminate some details when it can’t quite work out what to do. Look at the table tops near the two walkers in the frame.

GH5M2 Static detail
GH5S static detail

ISO 3200/4000

At this point I was presented an additional surprise the two camera started to have a gap in the metering so for a good few minutes the GH5M2 stayed on ISO 3200 while the GH5S was reaching out for more gain.

Ultimately this resulted in identical image quality in the parts with motion with the GH5S retaining some fine details better but the GH5M2 producing at the end a comparable result.

GH5M2 ISO 3200 Motion Detail
GH5S ISO 4000 Motion Detail

I won’t bore you with the static parts as they look identical.

ISO 4000/5000

The GH5M2 reached ISO 4000 however the GH5S had already moved to 5000. The consequence is that the image quality was the same.

GH5M2 ISO 4000 Motion Detail
GH5S ISO 5000 Motion Detail

Again the static parts were the same.

ISO 5000

Eventually both cameras were at ISO 5000 and here I could see a lead of the GH5S in the motion details but no benefit in the static details in terms of sharpness. However when you actually play the footage you can see the flickering of the temporal noise on the GH5M2.

GH5M2 ISO 5000 Motion Detail
GH5S ISO 5000 Motion Detail

The static details retain the same definition and resolution.

GH5M2 ISO 5000 Static detail
GH5S ISO 5000 Static detail

At this point is very clear to me that what is giving an edge up to now to the GH5S is the superior performance of noise reduction in camera as the actual dynamic range did not seem to be an element. If at all the sky becomes washed out sooner in the GH5S.

ISO 6400

From this point onwards the GH5S takes the lead however I would not say that the resulting image quality was very high. I would frankly avoid this ISO level but in desperate cases can certainly be used.

GH5M2 ISO 6400 Motion Detail
GH5S ISO 6400 Motion Detail

Perhaps more interestingly the GH5M2 although more noisy seems to preserver more details of the static part.

GH5M2 ISO 6400 static detail
GH5S ISO 6400 static detail

Noise Reduction

It became apparent during this test and you will see it clearly in the video that the GH5S has a very effective in camera noise reduction (even with NR=-5 this is still on) potentially because it does not have many pixels and can be quite aggressive with it. I tried using Neat Video with the GH5S however there was loss of detail, with the GH5M2 I could apply a temporal filter to the ISO 5000 you can see the results in the video and see what you think.

Light Levels

I was surprised to see the camera meter reading differently considering the matched set up. I also could see that the light level had to fall considerably so that the GH5S would have a benefit. In substance until both cameras were at ISO 5000 (I was using f/1.7 lenses) it did not look like the higher sensitivity of the GH5S was sufficient on its own to give a performance edge.

Higher ISO

I continued the test all the way to ISO 25600 for the GH5S the results were not exciting although you could say the camera does a decent job at showing some information. In general it seemed the camera was running out of dynamic range and also of image quality.

GH5S ISO 10000 static detail
GH5S ISO 10000
GH5M2 ISO 12800

At this point (ISO 12800) I would say that the benefit of the GH5S was now a full stop. In addition it can go to 25600.

GH5S ISO 25600

Low Light Sensitivity

I was expecting to see a material difference between the GH5S and the GH5M2 from ISO 1600 or at latest ISO 2500 with this gap growing at higher values. What I have seen instead is a bizarre progression where the GH5M2 would catch up and almost match the GH5S until ISO 4000 with a clear benefit only when the exposure was 5000 for both. It looks like in line with the aptina Dr Pix paper benefits only arrive near 0.01 lux*sec becoming higher later.

So we need 50% of ambient light * exposure time / aperture stop to be 0.01.

If we think about it f/2 1/60 this means aperture in stop is 2 which means a factor of 4. So working the inverse in order to get 0.01 lux*sec we would have 2*60*4*0.01=4.8 Lux.

If we consider an f/1/7 lens than this becomes 3.4 Lux and finally with an f/1.4 lens this would be 2.4 Lux.

In reality most f/1.4 or f/1.7 lenses really are just f/1.8 or f/2 so a value of 4 Lux for ambient light is reasonable. And this is the point where the benefit would start getting better as it goes darker. This is also consistent with my test the real performance difference started really to manifest a lot at ISO 5000 and became higher later.

We also have to consider thought that certain part of the image like the deep shadows will show a benefit sooner even if the ambient light is broadly sufficient. So it is not as clear cut as it would appear and the test confirmed such behaviours.

Conclusion

Perhaps the biggest surprise was how effective a traditional front illuminated sensor can be and how small was the gap with the GH5M2.

A key difference between my tests and others you can find on the net is that nobody actually runs tests with two cameras side by side and we have seen that at high ISO values the cameras did not meter exactly the same but what matters is the image quality at that point in time so the test still stands.

One thing has to be said though and this is that as of today if you want a micro four thirds camera style device (not a box or a cinema camera with no weather sealing) that works in low light with VLOG you are left with only one choice and that is the GH5S.

In the next part a wrap and some considerations about use cases and current competition for the GH5S.

Panasonic GH5S long overdue review – Part II Daylight Field Test

The second part of the test consisted in running the GH5S in parallel to the GH5M2 using CineD2. If you wonder why I did not use VLOG on the GH5M2 is because as discussed in a previous article VLOG on the GH5/GH5M2 is just a picture profile and does not really do anything other than deteriorate the noise in the shadows. So I used CineD2 as I wanted the maximum performance out of the GH5M2. The GH5S instead performs better in VLOG for reasons explained in the VLOG article as well.

So with the two cameras on tripods I went out for a walk and took several shots with similar exposure settings. Instead of using ISO 400 I used 200 on the GH5M2 which means the lens was one stop brighter on the GH5M2.

GH5S left and GH5M2 right

The practical tests confirmed what I was expecting based on the light box tests:

  1. The GH5S has a tendency to oversaturated reds and move blue to cyan so deep blues in the sky are almost never available. This was not so much of an issue during this test as the sky was overcast however you can see the clouds do not really have any blue tones.
  2. Auto white balance during the day performed consistently to the GH5M2 generating most times the same reading or at most a 200K difference. On this basis I do not understand why users speak about a magenta cast in some shots.
  3. The GH5S had better battery performance of the GH5M2 and I think this has to do with the LCD which is now much dimmer than the new camera as you can see in the picture.
  4. I did not see any more dynamic range in the GH5S. I would say a tad less than the GH5M2 on CineD2 at base ISO. This is visible in the second scene where I spot metered on the subject. Both camera had almost no tones left in the sky although they did not clip with the GH5M2 having perhaps an edge there.
Uncorrected out of camera waveform for the GH5S exposed to the right in VLOG
Uncorrected out of camera waveform for the GH5M2 exposed to the right in CineD2

Looking at the waveform after ETTR with the cameras showing near clipping you can see that the highlights are practically the same however VLOG has lower midtones and less darks.

This is the full video on youtube so you can make your own calls. The footage has been stretched to maximise DR ad hoc in the first scene and hues have been corrected for daylight. No other grading has been performed. In the second scene both cameras were maxed out and no further stretching has been done as it was not improving the scene.

The potential benefit of the GH5S over other models

The following table extrapolates the GH5S dynamic range considering a shift of 3dB in gain (ISO 400 -> 200 shifted)

ISO SettingGH5M2GH5SGH5Delta GH5M2 MaxDelta GH5 Max
4009.089.298.530.210.76
5038.719.048.220.330.82
6368.488.687.840.20.84
8008.178.397.530.220.86
10068.028.087.250.060.83
12737.657.766.950.110.81
16007.337.876.610.541.26
20116.907.636.300.731.33
25466.667.275.960.611.31
32006.286.995.650.711.34
40225.986.695.320.711.37
50915.646.374.970.731.4
64005.306.064.600.761.46
80455.015.714.310.71.4
101834.685.403.940.721.46
128004.335.043.590.711.45
16090
4.76

GH5M2

GH5
20366
4.39Avg0.5031251.16875
25600
4.07Min0.060.76



Max0.761.46
PDR table with gain shit

Please note this is an extrapolation I have not take measures however assuming VLOG impacts all cameras equally once gain is taken into account what you see there is that the GH5S has a potential benefit between 0.76 and 1.46 Ev over the original GH5 which is consistent with user experiences and website tests.

When you look at the GH5M2 the potential benefit drops to 0.5 and under 1600 is almost zero becoming 2/3 Ev when the GH5S is in high gain. This is also consistent to various tests on websites like dpreview and CineD.

The table does not consider however that CineD2 on the GH5M2 does accomplish more than VLOG in virtue of less noise and also does not consider the fact that some of the DR will be lost in the underexposure happening behind the scenes.

Part 2 Wrap Up

It is not difficult to see that the GH5S has good performance in daylight conditions however it does not really have any edge worth investing in it for this use case. So if you are not always at high ISO levels (>>1600) you may be getting better value from the GH5M2 that costs less takes photos and has IBIS. To be perfectly honest due to the way VLOG works I did not see major benefit even when I tested the S5 because the extra DR in the highlight was not really useful.

When we look at the GH5 instead the GH5S does remain superior but this is due to weakness of the GH5 itself. It really is quite clear that the software stack of the GH5 is really dated and the camera fairly noisy.

In the next article I will analyse two side by side shots of the GH5S and GH5M2 in low light.

Wildlife photography made easy