Blackmagic Pocket Cinema Camera 4K

[kye]

and the number one thing....   we definitely can't tell if it has MOJO!

[arant.joseph]

Yeah, just wanted to point out that the image looks much better in Lightroom.  Uploading it to the boards somehow cooled it down way to much and threw chroma noise into the skin.  Not sure what happened.  At any rate, I'm still impressed.....

[Savannah Miller]

A couple things:  The SD card that was used to record the "leaked" clips was actually quite fast.  It was the Sandisk Extreme Pro that the shooter used in either his Pocket or Micro cam (not sure) so there was likely some other issue as to why the recording was dropping frames.  Or maybe dropped frames just compound and create tons of problems causing the 12 fps mess.  There was some obvious tint problems with the colors and settings were hastily changed.  The clip was actually shot by changing the different ISO settings, so it's all over the place in terms of exposure and dynamic range.  There's only 10 stops in the 1600-25600 range.  It looks like the shots where people tended to prefer the exposure balance were around 1600-3200, likely the reason the highlights clip so poorly.

Most people grading the shots are just not great at color grading and didn't correct for some of the tint issues, hence why the colors look "off."  Plus on top of that, the shots that have more highlight retention are slightly underexposed too.

 

On top of that, color shifts with ISO changes too, and especially when going from standard ISO, to low light ISO mode.  So the standard ISO mode is likely a more "finished" color than that of the higher ISO modes causing further problems.  If someone had just exposed for 400 or 800 ISO the shots would have likely turned out 10x better.

[sanveer]

1 hour ago, Savannah Miller said:

A couple things:  The SD card that was used to record the "leaked" clips was actually quite fast.  It was the Sandisk Extreme Pro that the shooter used in either his Pocket or Micro cam (not sure) so there was likely some other issue as to why the recording was dropping frames.  Or maybe dropped frames just compound and create tons of problems causing the 12 fps mess.

Apparently not fast enough. If a 30p 4k camera is shooting at 12fps, there is a serious issues with writing speed. Also bitrates make a Huge difference, and that is why Panasonic issues directives for the 4k @ 400mbps shooting speeds wrt what cards Would be compatible. This may have Even Higher Bitrates. The guy who put the card in night have well used a 30MBps UHS-i card and let people judge based in 10fps, the video quality. It seems a little unfair, if not absolutely ludicrous. 

 

1 hour ago, Savannah Miller said:

There's only 10 stops in the 1600-25600 range.  It looks like the shots where people tended to prefer the exposure balance were around 1600-3200, likely the reason the highlights clip so poorly.

Actually there is a chart somewhere highlighting the exact dynamic range at the various ISOs. I believe it is like 1/2 or 2/3 stop lower at ISO3200 than it is at the 400-1600 range (I could be wrong though). 

If someone remembers where the chart is, Please share it here. 

 

I saw a (trailer of a) documentary shot on a moving train across hundreds of kilometres somewhere. It was shot on an F35, which also has open fans like almost all large film cameras. It was used in some terribly dusty and hot places. Except for rain and ice, I think BMPCC4k should do just fine in most environments. It may be even suffer a little dust, considering the sensor isn't exactly open and the fan cools and areas around it and not the sensor itself. 

[Savannah Miller]

If you look at the chart from the livestream, there's two ISO modes.  Native 400, and 3200.  Once you shoot 1600+ the Dynamic range drops to around 10 stops (vs 13) because it switches into the 3200 mode.

The guy who shot the test clip confirmed he was using the Sandisk Extreme Pro UHS-1 V90 which is rated at 95 MB/s and can sustain around 80MB/s+ continuous.  4K UHD is about 88MB/s in 24fps mode, so there has to be some other reason for the dropped frames or maybe it's just that once a single frame is dropped, other issues start compounding and it gets worse and worse.

[TwoScoops]

Regardless of discussion of whether it's the same sensor or not, how does the GH5s compare in that regard, in the 2500+ mode? Does it drop to 10 also?

[Savannah Miller]

2 minutes ago, TwoScoops said:

Regardless of discussion of whether it's the same sensor or not, how does the GH5s compare in that regard, in the 2500+ mode? Does it drop to 10 also?

I think it does.  RED Gemini also loses 0.5 stops of dynamic range when using the "low light" mode, but given they clearly say that the low light mode is for "low light only" and the fact that they generally overclaim their dynamic range, I feel like it's probably 1-2 stops as well.

[Kisaha]

I am not sure if it is wise and productive to try to figure out performance and I.Q issues from a "stolen" clip from a pre-pre-pre production model. I am sure they will short most things out, before release (around Christmas, that is!).

What it puzzles me, is the absence of 100/120 frames (without crop-ing). If it is capable of 4K/60, why not 1080/120? GH5S is doing 240 on a similar sensor (if not the same).

How exactly the "windowed" mode works?

[DBounce]

2 hours ago, Savannah Miller said:

If you look at the chart from the livestream, there's two ISO modes.  Native 400, and 3200.  Once you shoot 1600+ the Dynamic range drops to around 10 stops (vs 13) because it switches into the 3200 mode.

The guy who shot the test clip confirmed he was using the Sandisk Extreme Pro UHS-1 V90 which is rated at 95 MB/s and can sustain around 80MB/s+ continuous.  4K UHD is about 88MB/s in 24fps mode, so there has to be some other reason for the dropped frames or maybe it's just that once a single frame is dropped, other issues start compounding and it gets worse and worse.

I reported earlier that that the camera was dropping frames. It may well be that 12bit raw produces too much data for the current cards to write at 30 FPS.

Don’t be surprised to see the specs change on this camera.

[John Brawley]

25 minutes ago, DBounce said:

I reported earlier that that the camera was dropping frames. It may well be that 12bit raw produces too much data for the current cards to write at 30 FPS.

Don’t be surprised to see the specs change on this camera.

Goodness me.

The camera has two card slots. One is SD.  The other is....?????  And it can record through to USB-C as well.

JB

 

 

[kye]

59 minutes ago, DBounce said:

I reported earlier that that the camera was dropping frames. It may well be that 12bit raw produces too much data for the current cards to write at 30 FPS.

Don’t be surprised to see the specs change on this camera.

In addition to what @John Brawley said, the current write speed performance of SD and CFast cards might be why they put the USB-C on there.  Apart from making it super convenient by turning all the small editing SSDs we've got lying around into storage we don't have to re-buy, they might be the only things that can write 4K60 RAW until some of the tech catches up.

You'll find that it's hugely easier to design chips that can transfer data at a given speed than those that can read/write that data.  It took years for HDD speeds to out-grow the USB v1 and v2 spec, and apparently USB 3.2 is rated at 2500MBps - almost enough to do 4K RAW at 300fps!

I wonder if you can buy small USB 3 SSD all-in-one RAID drives?  They'd have crazy performance.

[Nathan Gabriel]

Can we stop down voting every post that can be remotely interpreted as critical? Everyone knows and agrees this is a revolutionary camera.

[Tone1k]

I'm not going to bother analysing the 'stolen clip'. It's completely pointless and all based on assumption. We know the camera was a pre-prod model so why is anyone bothering being so critical of it. 

I'm sure BM will release some footage soon that we can then judge properly.... Until then, everyone's getting worked up over nothing. 

[Myownfriend]

The Sandisk Extreme Pros would be able to handle 4K DCI at 24 fps in 4:1 RAW.

30 fps would be too much though. Prores 422 HQ would also be too high of a bitrate at 30 fps.

Do we know if the footage from NAB is 422 HQ?

[Savannah Miller]

15 hours ago, kye said:

In addition to what @John Brawley said, the current write speed performance of SD and CFast cards might be why they put the USB-C on there.  Apart from making it super convenient by turning all the small editing SSDs we've got lying around into storage we don't have to re-buy, they might be the only things that can write 4K60 RAW until some of the tech catches up.

You'll find that it's hugely easier to design chips that can transfer data at a given speed than those that can read/write that data.  It took years for HDD speeds to out-grow the USB v1 and v2 spec, and apparently USB 3.2 is rated at 2500MBps - almost enough to do 4K RAW at 300fps!

I wonder if you can buy small USB 3 SSD all-in-one RAID drives?  They'd have crazy performance.

No. Cfast 2.0 can write 4K 60fps RAW at 3:1 compression with no issues.  If anything SD cards especially the latest from SONY are getting quite fast too and can almost do 4K 60fps raw as well, but maybe there's a UHS-II limitation. The USB-C was intended for large capacity recording.

[Axel]

1 hour ago, Myownfriend said:

Do we know if the footage from NAB is 422 HQ?

There are at least two sources here, two stolen clips. The image arant.joseph attached here is not from the 12fps skipped-frame clip I was referring to. I had downloaded that 4-minute clip and analyzed it (posting):

ProResHQ, project frame rate 24, shooting frame rate 50, among other oddities.

The still that Joseph was grading and that jonpais found "pointilistic" is here first linked to on page 46, by Luke Mason, who claims to surreptitiously have acquired some footage:

People asked for original footage, but as far as I can see (took me ten minutes to dig that out, felt like an archaeologist), Luke didn't upload anything but jpeg stills.

 

[kye]

32 minutes ago, Savannah Miller said:

The USB-C was intended for large capacity recording.

What mode/codec do you anticipate would be used on the higher-end productions using this camera?  

I'm curious because when I look at those bit-rates and combine them with the size of typical media everything above 1080 seems to need large capacity recording

For example, a 64Gb card recording RAW 4:1 at 24fps only gives about 14 minutes per card.  Or 18 minutes in UHD ProRes 422.  These seem like quite low card capacities to me, but maybe you're rotating cards pretty quickly?  When I'm out shooting I only take a couple of cards out for a day and I have pretty large shooting ratios, but I'm shooting at much lower bitrates (~30MB/s).

[Savannah Miller]

The guy who shot it was a member of the Blackmagic facebook group.  He removed it hastily after Blackmagic requested it be taken down but others reposted.  If it's truly 422 then I see no reason why the clip is only 12fps and contains so many dropped frames.

Higher end productions like TV shows are shot usually 4:4:4 1080p.  So I could assume 1080p 4:2:2 will likely be used when shots are needed with this camera.  For Netflix I assume if this camera is used, maybe we'll see more 4K DCI Raw at 3:1 for VFX work although 4:2:2 Prores HQ I think fits within Netflix recording spec for 4K capture.

High Capacity recording is nothing these days as hard drives are getting cheaper and cheaper.  Really only reason against raw is the speed of the workflow as RAW is not much different from prores file sizes.

[Axel]

38 minutes ago, Savannah Miller said:

The guy who shot it was a member of the Blackmagic facebook group.  He removed it hastily after Blackmagic requested it be taken down but others reposted.  If it's truly 422 then I see no reason why the clip is only 12fps and contains so many dropped frames.

Mediainfo lists the framerate as "variable", maximum framerate 24, minimum 3, mostly 12, with 24p being the "project frame rate" and 50p the "shooting frame rate". This is a distinction and a naming convention in Apples FCP for "off-speed-frame rates" (term from BM) to generate slomo or timelapse. Since ProRes is an Apple codec, it makes sense that you'd find this metadata tag here.

The *actual* data rate was 384 Mb/s, and you are right: not too much for that Sandisk card. But four times that (50p instead of 12p) would have been.

With my Sony, I can take stills on a slow card, but once i try and choose 4k video, the camera tells me that I need a faster card. It looks the NAB pre-production P4k tried to record anyway, resulting in this error. ProRes is known to be variable bitrate, not variable framerate. 

[Savannah Miller]

Some TV shows shoot prores XQ, so file size is not the issue, it's just that they don't like raw.  Lossless raw might even be smaller than Prores XQ but the workflow is more expensive.