Which 4K camera for the masses? GH4 vs Blackmagic Production Camera

[CaptainHook]

Hey Andrew, in your article you make comment that the RAW from the BM4K is compressed 2:1, which sounds like you're assuming it's the same compressed raw as the Pocket Cam.. ?

 

The Pocket cam uses lossless compression, like zip compression. It's described in the cDNG spec, but i believe BMD were the first to ever actually do it which is why it took some time to develop.

 

The compression for the BM4K as written publicly by BMD will different, i.e it WILL be lossy - but they are calling it 'visually lossless'. Which means i guess there will be some compression in the raw, unlike the other BMD cameras. Again, since it's never been done it will most likely be released after the camera if officially shipping (i assume).

 

Just wanted to clear it up, and perhaps i misunderstood your article but it came across to me that way.

 

Cheers. :)

[dbp]

I still for the life of me have no idea what people are on about when they say you must shoot in 4.2.2 to meet some television standard. I have worked in broadcast television for years and have never ever ever heard of something 'rejected' because it isn't 4.2.2. Ever. Matter of fact, when working for television news, I would personally shoot plenty of full news packages in 4.2.0. Nobody cares. They filter it through a switcher. It's not like if you shoot something internally with this camera and then give it to the BBC or another national news outlet they'll go, "WHAT?! YOU AREN'T USING THE PROPER SUBSAMPLING?! WE CAN'T USE THIS!" and throw it out the window. News flash, people: cell phone video makes the news every single day. YouTube clips are pulled. Half the national news packages in the feeds that are used in broadcast aren't even full 1080p. This whole 'BBC Approved Color Space' thing is a load of malarkey and is only thrown around by folks who have absolutely no clue how television broadcast works.

 

I always wondered this too. Suppose you shoot stuff, it's well exposed and looks clean... and then you converted it to Pro Res / DNXHD or whatever, how would anyone know that it came from an AVCHD camera? I edited a provincial election ad a few years back and the footage was some HDV handy cam footage. No one batted an eye. They might *say* they require XYZ, but if you hide it and don't say anything, would they even know the difference?

[austinmcconnell]

They might *say* they require XYZ, but if you hide it and don't say anything, would they even know the difference?

You don't need to even hide it. That 4.2.2 'broadcast standard' thing is really just something video journalists latched onto when the DSLR boom happened to justify their equipment. I roll my eyes whenever I hear it used as a reason for people to not use DSLRs or the like for news. It all stems from it being the 'recommended' specs for news stations when purchasing cameras so that there's a bit of unity in the equipment across individual local stations.

 

The truth is no one even so much as glances at what camera you shot it on. If the aspect ratio or something is off, they just scale that sucker up til it fits the TV monitor. The producers who ultimately operate the switcher at broadcast have no clue what any of that '4.2.2 / 4.2.0' junk means. They don't care. Did you get the shot, or not?

 

The extent of codec knowledge TV Producers has is this:

Drag video file onto timeline ---> Export To---> Control Room ---> OK (Done). 

[Aussie Ash]

The BBC uses the EBU’s Recommendations for high definition cameras

 

List of BBC Aproved HD Cameras (as of April 2012)

Studio Cameras

• Sony HDC1500 • Sony HDC1550 • Sony HDC1400 • Sony HDC1450 • Sony HSC300 • Sony HXC100 • Grass Valley LDK8000 Elite Worldcam • Grass Valley LDK8000 Elite Standard • Grass Valley LDK4000 Elite 1080i

HD Handheld

• Canon XF305 • Canon XF300 • Sony PMW-EX1R – with external recorder using a bitrate of 50Mbps or above • Sony PMW-EX3 - with external recorder using a bitrate of 50Mbps or above

HD Shoulder Mount

• Panasonic HDX900 • Panasonic HPX371 • Panasonic HPX3000 • Panasonic HPX3100 • Panasonic HPX3700 • Sony PMW320 – with an external recorder using a bitrate of 50Mbps or above • Sony PMW350 – with an external recorder using a bitrate of 50Mbps or above • Sony PMW500

• Sony HDW F900R & 900 • Sony HDW 790, 750 & 730

HD Specialist

• Panasonic HPX2700 HDC27F & H • Panasonic AF101 – with an external recorder using a bitrate of 50Mbps or above • Sony CineAlta F35 • Sony SRW 9000 • Sony PMW F3 – with an external recorder using a bitrate of 50Mbps or above • Arri D21 • Arri Alexa • Panavision Genesis • Thompson Viper • Red

Mini Cameras

• Iconix HD-RH1 • Panasonic HCK10/HMR10 • Toshiba IK-HR1S • Toshiba IK-HD1

 

Recently approved :Red Epic,Canon 1DC

[theSUBVERSIVE]

It's ironic that some on this thread are saying "look at the broader picture, not just resolution" and then constantly repeating that they won't be buying the GH4 because it doesn't do one small feature of the overall image (4:2:2 internally).

 

Actually it does do 4:2:2 internally. The whole image pipeline is 4:2:2 until the compression kicks in and goes to 4:2:0. That counts for something.

 

Furthermore a full pixel readout from the sensor with true 4:2:2 sampling internally is more important than the final compression format. Want proof? See the Nikon D800 internal 4:2:0 vs HDMI 4:2:2... Not much difference, and still lots of aliasing and stair stepping. 4:2:2 is actually a very minor thing in the grand scale of things. Pixel binning, line skipping, all that stuff - there's no point having 4:2:2 if you are doing that. In 4K on the GH4 you have no pixel binning or line skipping, it's a full pixel readout, like a crop of a 16MP JPEG still to 8MP. If you're not satisfied by that at $2k then you really need to reassess your expectations. Feel free to spend $12,000 on the 1D C if you want internal 4:2:2 in 4K.

 

There will always be people with unreasonable complain that weren't going to buy it to begin with. Latest rumors goes for €1,499, if it's true, this camera is even more compelling like nothing ever before. 4K for this price? Plus 1080p VFR up to 96fps @200mbps ALL-I and @100mbps IPB, full readout, HDMI out 4:2:2. etc. Sure, there are things that could had been better resolved, like the 4K crop, lack of multi-aspect, the flexibility using the interface unit, etc. But even if it's really $1,999, there is nothing like this camera and let's not forget that even though this can be used for professional work with some standards to fill, this is ultimately a still camera form factor. In this level, I can hardly think of any must have feat that was left out so anyone would claim that they won't buy it because of that, anything that was left out can only be found on cameras much more expensive and clearly aimed at a different initial target.

[austinmcconnell]

 

The BBC uses the EBU’s Recommendations for high definition cameras

 

List of BBC Aproved HD Cameras (as of April 2012)

Studio Cameras

• Sony HDC1500 • Sony HDC1550 • Sony HDC1400 • Sony HDC1450 • Sony HSC300 • Sony HXC100 • Grass Valley LDK8000 Elite Worldcam • Grass Valley LDK8000 Elite Standard • Grass Valley LDK4000 Elite 1080i

HD Handheld

• Canon XF305 • Canon XF300 • Sony PMW-EX1R – with external recorder using a bitrate of 50Mbps or above • Sony PMW-EX3 - with external recorder using a bitrate of 50Mbps or above

HD Shoulder Mount

• Panasonic HDX900 • Panasonic HPX371 • Panasonic HPX3000 • Panasonic HPX3100 • Panasonic HPX3700 • Sony PMW320 – with an external recorder using a bitrate of 50Mbps or above • Sony PMW350 – with an external recorder using a bitrate of 50Mbps or above • Sony PMW500

• Sony HDW F900R & 900 • Sony HDW 790, 750 & 730

HD Specialist

• Panasonic HPX2700 HDC27F & H • Panasonic AF101 – with an external recorder using a bitrate of 50Mbps or above • Sony CineAlta F35 • Sony SRW 9000 • Sony PMW F3 – with an external recorder using a bitrate of 50Mbps or above • Arri D21 • Arri Alexa • Panavision Genesis • Thompson Viper • Red

Mini Cameras

• Iconix HD-RH1 • Panasonic HCK10/HMR10 • Toshiba IK-HR1S • Toshiba IK-HD1

 

Recently approved :Red Epic,Canon 1DC

 

 

Key word there being 'Recommendations.' This is not a requirement. This 'list' is meant to be a guide for the local stations when selecting cameras to purchase for their photogs who go out into the field. They select these cameras because they use a codec that plays smoothly with Grass Valley (the editing and ingesting software commonly used in TV news). The idea is, we need a camera that imports quickly into our servers so Jimmy the photog can shoot/import/cut/send to control room within minutes in case there is breaking news. Additionally, many journalists shoot and edit by themselves, having only hours to cut together their package for airtime. These folks aren't doing complicated edits, because they don't have any idea how, beyond basic cuts and voice overs. They're too worried about being dressed and prepped in time for their live shot to worry about color correction or anything like that. So these 'recommended cameras' are ENG cameras designed to do as much in-cam as possible, with editing an afterthought.

 

I'm guessing anyone mulling over the 'GH4 vs BMPC' decision aren't news photogs or multimedia journalists with the BBC. You're likely thinking about using it for documentaries. In that case, you'll have plenty of time to edit, color correct, etc. to get it perfectly cut together for broadcast. The '4.2.2 standard' thing isn't meant for you. It's meant for the company when choosing which cameras to purchase for their news team, so that they get the ones that play nicest with the control room, AND so they can have unified equipment in case a journalist's camera breaks, they wont have to waste time trying to figure out how to use a different model. 

[Caleb Genheimer]

I'm eager for that 4K Blackmagic camera to really get out in the wild for a few months. Its two features short of my "perfect camera", and I suspect that, given enough money, certain shops would mod it for me. If I can get that EF mount modded to something shorter for a grand or two, I'd be happy. If the new mount included some sort of ND system (even just a slot I can drop small circulars into), I'd be over the moon.

S35, RAW with global shutter is a trifecta impossible to ignore, especially at $4K.

[Jeroen de Cloe]

I'm mostly interested in the stories people will tell with the GH4. Can't wait to see the vimeo channel and see how they can use the camera's specs to their benefit.

[NRT]

I'm sure Panasonic would love to see you an AF200 instead!

Let's see what comes at NAB.

 

I'd love to see me with one as well!

 

I'd be amazed if they produced an AF200, since it would overlap with so many of the GH4 features.

[NRT]

Tell you what though, if the GH4 had the Olympus 5 axis stabiliser on top of it's current feature list - I reckon I'd wet myself.. In fact, I think i might.. ahh, that's goood...

[etidona]

Maybe sometimes things are more simple than they looks.

Could be 4k 4:2:2 = files too big for the SD ?

Please notice the gh4+the brick+battery+external recorder+shoulder mount will be roughly the same size of a 1/3" shoulder camera as the jvc gy-hd750!!!

What i really dont't understand is the choice to crop the sensor in 4k just to mantain 16MP stills. This is a commercial choice without a real practical sense!

[TJB]

I always wondered this too. Suppose you shoot stuff, it's well exposed and looks clean... and then you converted it to Pro Res / DNXHD or whatever, how would anyone know that it came from an AVCHD camera? I edited a provincial election ad a few years back and the footage was some HDV handy cam footage. No one batted an eye. They might *say* they require XYZ, but if you hide it and don't say anything, would they even know the difference?

This is a reply to forum member who made a comment about broadcast news and colour subsampling. I know this is probably the wrong website to make this comment - please excuse me.

 

Generally broadcast News acquisition uses 4.2.0 chroma subsampling. Simply because News material is not graded or used for green screen before it goes to air. 

 

Some broadcasters request but don't necessarily require acquisition for longer format programs such as documentary material to be shot at a certain standard. This ensures that the material can be graded easily. The standard for SD or HD material is generally 50/100 Mb/s 4.2.2.

DVCPRO 50 is one such codec which is accepted.

Some programs have a lower ceiling on this standard and accept 4.2.0 material for documentary work. Think GoPro etc.

 

It is very hard to see the difference between 4.2.2 and 4.2.0 and that is exactly why it is used - colour information is harder for the human eye to judge as luminance information. Therefore to compress the image further, codecs throw out half the colour information knowing we probably won't notice.

 

Since the 5DMKII came about we've been asking for better image quality. This website is one of them. Andrew Reid particularly has called for higher bit rates and better codecs to improve image quality. This is now happening - however for those of us who grade material or simply don't care for banding on a blue sky for instance - a higher standard colour sampling codec is needed. Andrew knows this and so does Panasonic.

 

I think the GH4 looks like a great camera however it is not a great camera if I have to bolt on two additional boxes which is clumsy and does away with portability just to get it to a standard that we have been pushing for for 6 years. I personally would not turn up to a paid job with a GH4 and XLR/SDI box and an external recorder. I would however turn up to a paid job with a GH4 if it had internal 4.2.2 recording and a simpler / smaller XLR adapter. For of us who make a living as videographers/ cinematographers/ cameramen/women - this is actually a big deal and not just an idle gripe for the sake of it. 

 

It's ok that the new GH4 doesn't record a minimum standard for broadcast HD requisition. Andrew and Panasonic clearly thinks it's ok as well.

But it is one big reason why I and others won't be using a GH4 for work where reputations and day-rates are held accountable.

[Michael Ma]

I'm sure the GH5 will do 1080p at 10 bit 422 in body.  I can wait 1 year no problem.  I think the GH4 could have done it.  I just don't understand why it doesn't.

[TJB]

Tiresome. I didn't say people don't give a rats ass about 4:2:2 I said most people don't give a rats ass about having their camera on a short-list drawn up by a man in a cupboard at television centre.

Couldn't agree more Andrew. It is indeed very tiresome!

What would be even more tiresome is only being able to use XLR inputs on a tripod with mains power or a battery brick attached.

Was that really your idea?

[Marino215]

Please clarify if you can. Its my understanding that 4k 8-bit 420 scaled down to 2k can create a 10 bit 422 file? I've read a couple times that 4k 10-bit 422 can be scaled to 12-bit 444 1080p. If that's the case, with it's improved low light capabilities makes this camera an amazing camera for photo journalists, reporters, B cam on high end jobs, underwater, just a fabulous all around doc tool. Would I seek investors, hire big actors, have a big crew etc with this camera being my A cam? No, of course not. Shorts? Why not. My point is how far we stretch or even downscale the image its all there for us one way or the other. Yes most drool over affordable, quality 10-bit out of the box but in this day and age with affordable post prod tools, with a little work we can get there. If you absolutely need 4k and 4k only get a Red, f55 or wait for the BM. If I understood it correctly,(I pray I did) for me that would be even more amazing than the 4k itself. Thanks

[zephyrnoid]

Excellent comparison.
Some points to ponder.
"Sensor size and your choice of lens is indelibly linked – an important thing to consider..."
Indeed. So let's put the squeeze on Panasonic to get it right. APS-C/DX !
When discussing critical highlight exposure (zoneVIII) it helps to mention that pros, reflexively lock in that highlight tone and holding VIII becomes a non issue in post.
Also. The BMCC is not a hybrid. It's an experimental beta product. The GH4 is a bone afide hybrid. But you've already implied the distinction.

[zephyrnoid]

I'm sure the GH5 will do 1080p at 10 bit 422 in body.  I can wait 1 year no problem.  I think the GH4 could have done it.  I just don't understand why it doesn't.

If you read all my posts you'll have the answer. They're rolling out incremental upgrades to make adopters pay for the bigger milestones down the timeline

[zephyrnoid]

You missed two key points about the GH4
1. It's a hybrid FOR hybrid shooters, like I used to be. Shoot stills for bread n butter, shoot video for bread and butter and fun.
2. It's a transitional camera. A fuller integrated 4k camera SHOULD emerge from Panasonic that is boxy and does not required external box or 4k recorder. My guess is it will be called Arri Amira ;)

This is a reply to forum member who made a comment about broadcast news and colour subsampling. I know this is probably the wrong website to make this comment - please excuse me.
 
Generally broadcast News acquisition uses 4.2.0 chroma subsampling. Simply because News material is not graded or used for green screen before it goes to air. 
 
Some broadcasters request but don't necessarily require acquisition for longer format programs such as documentary material to be shot at a certain standard. This ensures that the material can be graded easily. The standard for SD or HD material is generally 50/100 Mb/s 4.2.2.
DVCPRO 50 is one such codec which is accepted.
Some programs have a lower ceiling on this standard and accept 4.2.0 material for documentary work. Think GoPro etc.
 
It is very hard to see the difference between 4.2.2 and 4.2.0 and that is exactly why it is used - colour information is harder for the human eye to judge as luminance information. Therefore to compress the image further, codecs throw out half the colour information knowing we probably won't notice.
 
Since the 5DMKII came about we've been asking for better image quality. This website is one of them. Andrew Reid particularly has called for higher bit rates and better codecs to improve image quality. This is now happening - however for those of us who grade material or simply don't care for banding on a blue sky for instance - a higher standard colour sampling codec is needed. Andrew knows this and so does Panasonic.
 
I think the GH4 looks like a great camera however it is not a great camera if I have to bolt on two additional boxes which is clumsy and does away with portability just to get it to a standard that we have been pushing for for 6 years. I personally would not turn up to a paid job with a GH4 and XLR/SDI box and an external recorder. I would however turn up to a paid job with a GH4 if it had internal 4.2.2 recording and a simpler / smaller XLR adapter. For of us who make a living as videographers/ cinematographers/ cameramen/women - this is actually a big deal and not just an idle gripe for the sake of it. 
 
It's ok that the new GH4 doesn't record a minimum standard for broadcast HD requisition. Andrew and Panasonic clearly thinks it's ok as well.
But it is one big reason why I and others won't be using a GH4 for work where reputations and day-rates are held accountable.

[Peter J. DeCrescenzo]

Hi Andrew: Thanks for a good article.

 

BMD says the BMPC-4K sensor is "21.12mm x 11.88mm", not S35 motion picture frame size. Perhaps you should update the diagram in the article?

 

Diagrams are a helpful way to show how the GH4's sensor is smaller (less wide) than the BMPC-4K sensor when both cams are in UHD (3840 x 2160) mode. Likewise it would be good if the diagram also showed how the GH4 crops its sensor when in full 4K mode.

 

The GH4 looks to be an improvement on the GH3 in every way. Eventually I'll probably add a GH4 to my GH1, GH2 & GH3 collection, but hopefully my BMPC-4K will ship first!

 

Cheers.

[Andrew Reid]

Thanks Peter, yes I'll update it. Didn't realise it wasn't actually Super 35.