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nutmegger
03-28-2016, 09:43 PM
Any chance Panasonic will offer 10-bit 422 internal recording in a future upgrade of the DVX200? I currently shoot with a Canon C100 and record 10-bit ProRes to an external Ninja Blade. I'm looking to upgrade to 4K, but would prefer not to have to record to an external device. The DVX200 is within my budget but what is holding me back is the lack of 10-bit internal recording.

ReelWorksMedia
03-28-2016, 09:47 PM
Don't want to give you bad news...but your C100 does not output 10 bit. The Ninja records 10 bit...but the C100 does not deliver it to the ninja. The ninja records the 8 bit C100 signal in a 10 bit wrapper.

nutmegger
03-28-2016, 10:00 PM
I'm aware that the C100 is a 8-bit camera and the Blade records a pseudo 10-bit. A couple of months ago I was at Abel Cine in New York for a Red event and while there I had the opportunity to check out the DVX200. I liked what I saw. I prefer the DVX200 form factor over my C100. I could use my Ninja Blade with the DVX200, however I want to keep things as simple as possible.

Barry_Green
03-29-2016, 07:37 AM
There is no possibility of the DVX200 recording 10-bit internally. It does, however, output a true 10-bit signal.

nutmegger
04-26-2016, 08:29 AM
There is no possibility of the DVX200 recording 10-bit internally. It does, however, output a true 10-bit signal.

Hi Barry. I have been reading your DVX200 Guide. On page 96 of the guide you write that internal recording is 8-bit 4:2:0. Further down on the page you write "However, an external recorder is not necessarily required, especially if your final delivery is 1080P (or 720P or standard-def). By recording internally in UHD or 4K, you can downconvert to 1080P (or smaller) and the resulting footage will be 10-bit at 4:4:4 color sampling. See the article on Benefits of 4K for more information. " Can you clarify what you mean by the above statement?

Thanks.

NorBro
04-26-2016, 08:45 AM
I would like to hear more about this too.

My main question is does working with the 4K footage in a HD timeline provide better results as opposed to creating an HD master from the 4K master?

Also, it's been heavily debated that doing either above is not the same as recording true 10-bit 4:2:2/4:4:4 HD.

Personally, I don't think many would notice a difference and it may only be beneficial in certain type of work (gs/vfx/etc).

Bassman2003
04-26-2016, 09:50 AM
The only problem I see with this theory is any shortcomings of your 8bit 4k recording are going to be burned into the file. So if you have an overexposed sky recorded in 4k, putting this on a 1080p timeline is not going miraculously allow you to recover the highlights. Now if the original recording was in 10bit 4:2:2 you probably would have a better shot. If I am wrong, then please correct me.

Also, I would assume that any color improvements diminish if you zoom in on the 1080p timeline. Which is why many want to shoot in 4k in the first place. Right?

Simply Cinema
04-26-2016, 11:01 AM
Hi Barry. I have been reading your DVX200 Guide. On page 96 of the guide you write that internal recording is 8-bit 4:2:0. Further down on the page you write "However, an external recorder is not necessarily required, especially if your final delivery is 1080P (or 720P or standard-def). By recording internally in UHD or 4K, you can downconvert to 1080P (or smaller) and the resulting footage will be 10-bit at 4:4:4 color sampling. See the article on Benefits of 4K for more information. " Can you clarify what you mean by the above statement?

Thanks.

I believe what Barry was saying in the manual is that if you record 4k or UHD internally at 4:2:0, when you down-convert that footage in post to 1080p, it comes out being 10bit 4:4:4 at 1080p. The extra resolution of 4k gives the down-convert process the pixel information it needs to resolve 10 bit 4:4:4 1080p.

Barry please correct me if I misunderstood that.

AndreeOnline
04-26-2016, 11:14 AM
Scaling 8bit footage down does not turn it into 10bit.

The color precision can be said to increase because you're starting with a surplus of discreet pixels that will be blended into 1/4 of the original number.

pancam
04-26-2016, 11:54 AM
so I know the DVX200 HDMI out for 10-bit
I ordered Blackmagic Video Assist

Barry_Green
04-26-2016, 12:48 PM
I believe what Barry was saying in the manual is that if you record 4k or UHD internally at 4:2:0, when you down-convert that footage in post to 1080p, it comes out being 10bit 4:4:4 at 1080p. The extra resolution of 4k gives the down-convert process the pixel information it needs to resolve 10 bit 4:4:4 1080p.

Barry please correct me if I misunderstood that.
Yes you are correct.

In a 3840 x 2160 image recorded at 8-bit 4:2:0, you will have 1920 x 1080 color resolution. When downrezzing 3840 x 2160 down to 1080p, you will end up with 1920 x 1080, and you will maintain that 1920 x 1080 color resolution. As such, working with 3840 x 2160 4:2:0 footage gives you 1920 x 1080 4:4:4 footage after downconversion.

The 10-bit thing is trickier. When summing four pixels into one, i.e. when turning each 2x2 block of UHD pixels into a single HD pixel, you don't average them, you just sum them, and that lets you retain the individual variations in shade that result in getting 10 bits worth of data. However, it's not necessarily the exact same image as you would have gotten if you'd shot in a true 10-bit format in the first place. You can, however, use the extended data to greatly, hugely reduce banding if you do a proper bicubic downconversion. A simple 2x2->1 downconversion won't do much to minimize banding, but a bicubic (or even bilinear) downconversion can make huge improvements in 8-bit banding (and other 8-bit limitations).

NorBro
04-26-2016, 12:58 PM
Would you recommend editing the 4K/UHD footage in a 1080p timeline?

Or does editing everything in a 4K project and then making an HD master provide the same result?

Thank you.

Barry_Green
04-26-2016, 03:04 PM
That depends on your editor. I've done it both ways and it seems to work out fine in Vegas either way.

pancam
04-26-2016, 10:00 PM
sorry, finally is it possible to record in the external recorder true 10-bit signal in 1920x1080?
(from HDMI, or SDI out)

Barry_Green
04-26-2016, 11:34 PM
Yes, it has always been possible to do so. The SDI and the HDMI both support 10-bit 4:2:2 output to an external recorder.

TDCat
04-27-2016, 02:56 AM
Hi,

If anyone does not own an external recorder or does not yet own the DVX200 but it considering it, I'm adding some ProRes 10-bit 4:2:2 clips online here http://bit.ly/10bitexternal if you want to download and have a play at grading on your system or checking how the external clips look.

Sorry if they're a bit boring. I'm too busy at my day job to embark on any projects at the moment so it's all playing and testing right now. They might be useful for someone! :-)

Torsten.

pancam
04-27-2016, 05:19 AM
Thank you, Barry

Barry_Green
04-27-2016, 12:54 PM
Ah - I should mention, the 10-bit output is only 10-bit if you specifically enable 10-bit output in the SYSTEM menu. If you don't enable 10-bit, then the output is 8-bit 4:2:2 and you can simultaneously record internally. If you enable 10-bit, then the output is 10-bit 4:2:2, but you can no longer record internally.

JRJphoto
04-30-2016, 08:53 AM
What are the Mbps/bit rate when recording external 4:2:2 10-bit? Is it exactly the same as whatever format I've chosen? Say, FHD All-I @ 200Mbps. Thanks.

bpap
04-30-2016, 09:35 AM
Barry,

somewhere here in the forum I have read your sentence, that if I want to have the best quality-results in 1920x1080 (FHD), I should use the “Dual Codec recording”. That means recording card 1 in UHD and recording card 2 in FHD at the same time.
My Question: what is the source of the FHD-files? Is it a downconversion from the UHD recordung files inside the DVX and what kind of downconversion?

Thanks, would be very interesting

Barry_Green
04-30-2016, 10:04 AM
What are the Mbps/bit rate when recording external 4:2:2 10-bit? Is it exactly the same as whatever format I've chosen? Say, FHD All-I @ 200Mbps. Thanks.

It doesn't work that way. Your choice of internal doesn't affect the output. The output is always uncompressed, so the mbps and format is up to the external recorder. If you are using a ProRes recorder in ProRes 422HQ then the recording will be 880mbps at 10-bit 4:2:2.

The only question is whether it will be 8-bit or 10-bit. If recording internally too, the external output is limited to 8-bit. If recording externally only, you can choose 10-bit.

Barry_Green
04-30-2016, 10:06 AM
Barry,

somewhere here in the forum I have read your sentence, that if I want to have the best quality-results in 1920x1080 (FHD), I should use the “Dual Codec recording”. That means recording card 1 in UHD and recording card 2 in FHD at the same time.
My Question: what is the source of the FHD-files? Is it a downconversion from the UHD recordung files inside the DVX and what kind of downconversion?

Thanks, would be very interesting

It is a rescaled version of the UHD frame. It is the full UHD uncompressed frame, scaled down to FHD, and then recorded as 50mbps 4:2:0.

JRJphoto
04-30-2016, 10:35 AM
It doesn't work that way. Your choice of i ternal doesn't affect the output. The output is always uncompressex, so the mbps and format is up to the external recorder. If you are using a prores recorder in ProRes 422HQ then the recording will be 880mbps at 10-bit 4:2:2.

The only question is whether it will be 8-bit or 10-bit. If recording internally too, the external output is limited to 8-bit. If recording externally only, you can choose 10-bit.

Fantastic! That's great news. Thanks so much, Barry.

TDCat
05-06-2016, 07:16 AM
It is a rescaled version of the UHD frame. It is the full UHD uncompressed frame, scaled down to FHD, and then recorded as 50mbps 4:2:0.

I understand why this would be beneficial but doesn't the standard FHD setting sample at pretty much the maximum resolution for the sensor (5K'ish) and downscale to FHD? Wouldn't this logically be the better choice (apart from the fact you do not have the UHD version too)?

Thanks,

Torsten.

Barry_Green
05-06-2016, 10:50 AM
but doesn't the standard FHD setting sample at pretty much the maximum resolution for the sensor (5K'ish) and downscale to FHD?
No, it doesn't. It uses a technique called "pixel mixing" (along the lines of pixel binning). The results are much faster scan rates and wider field of view, but somewhat lower resolution and increased aliasing.


Wouldn't this logically be the better choice (apart from the fact you do not have the UHD version too)?
It would be, if that was what is happening, but generally it isn't. The only way you can get it to do what you describe is to use the "Dual Codec" function, and record UHD on one card and FHD on the other. In that case, it does an on-the-fly rescale of the fully-sampled UHD frame and records an exceptionally sharp, clear, crisp HD frame. It's the highest-resolution HD the camera can make. However, the drawbacks are that when you're in dual-codec you can't use the hybrid OIS, you can't use the i.Zoom, and you don't get the wider FOV or faster scan rates that FHD mode normally provides. If you don't need those, and you only need FHD, then it's a great way to get the best-quality FHD while simultaneously having a UHD master "just in case".

When you use the normal FHD mode (the "pixel mixing" mode) you get a wider FOV, faster scan rates for minimized skew/rolling shutter, hybrid OIS, variable frame rates, and i.Zoom. But the results are a little softer (still way sharper than my AF100 or an HPX170/HVX200, but not as sharp as a PX270 for example), with more aliasing in the image.

TDCat
05-06-2016, 11:48 AM
Makes sense. Thanks for the clarification. I will definitely give that a try.


UHD master "just in case".

Hehe...it's funny to think of it that way round.

TDCat
05-07-2016, 05:56 AM
In that case, it does an on-the-fly rescale of the fully-sampled UHD frame and records an exceptionally sharp, clear, crisp HD frame.

Does this impact the SDI out in anyway? If the camera is set to UHD and the SDI to FHD (I only have a FHD external recorder), do you know whether any of this would come into play? I don't really know enough about how the SDI out processes it's feed to even take a guess.

Barry_Green
05-07-2016, 10:13 PM
The SDI is always a top-quality resize from the UHD, if outputting UHD or FHD.

When in FHD mode it outputs an uncompressed version of the pixel-mixed FHD scan.