Panasonic GH5: The Overheating Gate and the IBIS rant!

(Part 1)

two [EPIC] bits
9 min readSep 23, 2016

Let’s start by saying that the Panasonic GH5 was just pre-announced, it basically means that they announced that the camera is under development, something we already knew and they also said that the full announcement should happen in the near future, which translates to “sit and wait”.

Do you know how many slides highlighted the specs of the GH5?

ONE.

credit: https://twitter.com/ElWheet/status/777823620596764672

Yes, ONE SINGLE SLIDE!

I’ve seen a lot of people complaining — after all, this is the Internet — but most of them didn’t even know that this was not a proper product announcement.

They talked about the GH4 in “the prologue” video, they showed a slide about what the GH4 brought to the table, then just a single slide talking about 4 feats and more, then they started talking about lenses and how they want to achieve 8K by Tokyo 2020.

It has to be clear to people panicking that this camera is still a few months away from shipping and that the fact that Panasonic didn’t talk about certain feats is not conclusive as for saying that the camera won’t have it, it’s just that the camera is clearly still in development.

Most of the hype came from people wanting to know more rather than Panasonic making the GH5 the focus of their presentation. I’m quite sure that Panasonic actually wanted the focus to be on their new products and GH5 was more like “hey, it’s coming, Kumamoto Earthquake brought some delays but the GH5 will come soon, hang in tight, it has 10-bit 4:2:2 and 4K 60 fps, wait for the GH5!”.

People need to calm down and be a bit more logical, but I get it, it’s the Internet, asking people to have patience is actually being a crazy person, but let’s try that for a bit.

Key Feats Confirmed:

  • 10-bit 4:2:2 Internal Recording
  • 4K 60 fps
  • 6K Photo mode
  • Audio interface with 2 XLR ports
  • External Grip

Key Missing Feats:

  • In-Body Image Stabilisation
  • No extra crop in 4K
  • Codec and Media
  • Dual Card Slot
  • Improved Continuous AF
  • 1080p 120+ fps Slow Motion

The IBIS Rant

Panasonic is yet to confirm that the GH5 will have IBIS or not. Logically speaking, there is no reason for Panasonic to not have IBIS. Some people keep mentioning the flawed A6300 or some other Sony product as for the reason of that but as I already talked about, that’s a completely different situation.

The GX80/GX85 has IBIS and it works well in 4K video without any overheating issue at all. The just announced G80 has a second generation IBIS, the Dual IS MK II. The GH4 was the coolest of all 4K cameras, to overheat that camera even with IBIS, you would need to push a lot, even the Samsung NX1 which has H.265 HEVC codec that is supposedly more processing intensive didn’t overheat. I know it didn’t have IBIS but it’s just a few examples to show that none of that seems impossible.

Do you know who else has 4K and IBIS?

The Olympus E-M1 MK II!

The Olympus E-M1 MK II was also pre-announced but with much more details than just 4 key points like the GH5. The E-M1 MK II has IBIS, new AF algorithm, 121-point Dual FAST AF, EVF with 120fps and Cinema 4K up to 237mbps of internal recording codec.

But let’s take a look at what Olympus has shown regarding recording formats.

Cinema 4K: up to 237mbps

UHD: IPB up to 102mbps

FHD: All-I up to 202mbps and IPB up to 52mbps

This is odd.

The 4K 240mbps is something new and groundbreaking, even more for Olympus, they seem to be wanting to redeem themselves for better video but why would Olympus develop a 1080p All-I 200mbps codec? Why waste resources developing something that is not even that marketable?

Oddly enough, it may be the same codec found on the GH4 and the new FZ2000. Would Panasonic and Olympus be sharing some tech? Or maybe it’s not Panasonic, but Sony the one proving these codecs? I don’t know but it wouldn’t be surprising if Olympus helped Panasonic with some tech like IBIS and then Panasonic helped Olympus with video encoding. It would be a bit conflicting but who knows?

Anyway, it’s hard to speculate on that, but this doesn’t seem like something Olympus would develop in-house, so they probably paid for it and either way, if they went to that extent, I think we can expect a better video quality.

Olympus doesn’t say if the 240mbps codec is 8-bit 4:2:2 or just 4:2:0 or if it’s IPB or All-I. But I hope that at least this puts a stone on top of the fallacies I’ve been reading, as if the GH5 won’t have IBIS because of the higher bit rate or something like that.

Is Overheating the main issue for IBIS?

Some people talked about how 10-bit 4:2:2 would generate more heat than the usual 8-bit 4:2:0 because there are more data but I don’t get it, where did people reach that conclusion?

More data alone means nothing, I seriously doubt that a camera would overheat simply because of data rate. It’s never one thing, data only matters if it’s a lot of data transfer AND there is a lot of processing going on. In this case, there would be more data output but in theory, it’s also less compression.

The GH4 was already capable of outputting 10-bit 4:2:2 via HDMI, which means that instead of compressing and encoding to 8-bit 4:2:0 it would only need to encode it.

When outputting 10-bit data the GH4 wasn’t capable of recording to the SD card simultaneously as opposed to when it’s outputting 8-bit 4:2:2 via HDMI. It doesn’t seem like something that all of sudden would generate too much heat and Panasonic already showed that the usual 4K 8-bit 4:2:0 run smoothly with IBIS.

Not just that, with Fuji we’ve learned that that battery might be an issue too, because when there are processing peaks, it will drain more power from the battery, making it generate more heat as well. And of course, the sensor is another component that generates heat while working.

My point being, if IBIS makes the sensor less efficient to dissipate heat, you can improve the heat dissipation somewhere else by using different materials, changing the battery compartment, optimizing the engine, etc.

Transistors keep getting smaller, new processors use new chips, the new chips are smaller and much more energy efficient. You can use more cores and underclock them to generate less heat.

There are a lot of different solutions if you are really willing to solve the overheating issue. The GH5 has a big enough body so the heat is not trapped like it’s in the A6300 or A7 bodies and as I’ve shown, there are plenty of ways to help the heat dissipation process aside from just a heat sink on the sensor.

Have Panasonic ever showed any product that had any overheating issue at all? No, so basically people are making claims and assumptions based on other manufacturers’ issues. So can we stop the fallacies already?

Why does Sony’s cameras overheat?

I blame this Overheating Gate bit on Sony, they were the ones that opened the Pandora’s box.

The A7s II and A7R II have IBIS and they do have overheating issues in 4K, but the A6300 doesn’t have IBIS and it still overheats. Sony released a firmware update that seems to make the camera more efficient but still didn’t solve the problem, so overheating is still a liability.

A lot of people don’t know but some of the Sony NEX cameras also overheated and that just in 1080p — without IBIS. Funny enough, when they made slightly bigger bodies like the NEX-6 and NEX-7, these cameras didn’t show the same problem as the most compact of the family did— the NEX-5 line up.

So one should start wondering that Sony’s issue with overheating is not IBIS, but simply their obsession over the tiniest and most compact body possible, which is certainly not very efficient when it comes to heat dissipation.

If Sony so wanted, they could increase the body just slightly and the problem would be solved, but as it seems to me, Sony is partially using it to protect their video cameras and they’ll keep doing it as long as people are okay with it and keep buying their cameras — aka Canon mantra. The other part is so they can launch bigger bodies in higher-end cameras that won’t have that same issue.

Sony just announced the A99 II at Photokina, which has a bigger body — bigger than an E-mount would need to be —but I’m pretty sure that camera won’t overheat during 4K shooting.

Panasonic and IBIS

The new Panasonic FZ2000 has IBIS and it records without time limit, just to say that unlimited recording with IBIS is already possible. The new compact LX10 also has the Hybrid IS but it turns it off in 4K and 1080p 120fps. I know that the FZ2000 and the LX10 use a 1" sensor but my point is that Panasonic has different solutions for different situations.

Worst case scenario, Panasonic just have to turn IBIS off in more extreme cases like 4K 60 fps or simply put a time limit for using IBIS in 10-bit 4:2:2.

The GH5 seems beefier than the GH4, so there are more reasons to believe that they should be able to put IBIS in the GH5 than not. Actually, we can even think that the IBIS in it will be even more advanced than the one in the G80.

Think about that, back in July of 2015 Panasonic announced the GX8 that had a more advanced IBIS than the GX7, then in April of 2016 they announce the GX80 which finally has the 5-axis IBIS working with 4K, 5 months later, at Photokina 2016, they announce the G80 with the second generation DUAL IS.

The GH5 seems to be about 6~8 months away from shipment. Don’t you think that Panasonic would be able to fix any possible overheating IBIS related issue by then? Or even that there might not even be such an issue, they simply are working on it so they can announce an improved version of it. Maybe they are simply trying to figure it out what IBIS can cover and what not.

So, IBIS or not IBIS?

To be fair, I don’t discard the possibility of not having IBIS at all. It’s just that most logical arguments lead me to believe that the GH5 should will have IBIS. There is a lot I still don’t know and I’m hardly a camera engineer specialist or something, but I still think it’s unlikely to not have it but it’s still possible, of course.

Panasonic is well aware of how much people have been wanting IBIS for a GH camera, people have been asking for that since the original E-M5 managed to make it work in video via firmware update. People asked for IBIS in the GH4 too — but Panasonic didn’t have the technology working at the time. If Panasonic doesn’t make IBIS work in the GH5, a lot of people will be disappointed and some will prefer the G80 and some other might start looking at the Olympus E-M1 MK II.

You never know but it would be a huge business mistake if Panasonic, for some reason, decides not to use IBIS in the GH5. We’ll have to wait, I think that sooner than later Panasonic will end up spilling the beans, they don’t need to say what it will do, just say that it will be there and people will feel more at ease.

Part 2: Codecs and AF improvements Speculation

Part 3: The Mysterious Photo 6K and Mysterious Sensor!

Part 4: Slow Motion, ProRes/HNxHR and Final Thoughts

Extra: The Sensor has to be Multi-Aspect!

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