Ursa 12K - Compression Options and Delivery Formats

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devinpickering

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Ursa 12K - Compression Options and Delivery Formats

PostWed Jan 26, 2022 3:25 am

Hi everyone,
I'm a DP based out of upstate NY, I help run a production company and we just upgraded our G1 to a 12K, we also own a bunch of pockets. I just started shooting with the 12k and of course, the image has an incredible amount of detail and looks great so far for the most part. I could use some help though in regard to limitations to compression ratios. Specifically comparing 18:1 12K 24p to let's say 12:1 or 8:1, I'm basically trying to solve the data size issue in working with 12k in a documentary space, by taking a look and trying to understand whether we should be a little more conservative and record in 8k for most projects to deliver in 4k, or if we should try to embrace a higher compression ratio of say 18:1. I'm trying to decide if the drawbacks of using a ratio of 18:1 at 12k, is a better acquisition format than a lower compression of 8:1 8k would give a better image while conserving data.
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John Brawley

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Re: Ursa 12K - Compression Options and Delivery Formats

PostWed Jan 26, 2022 3:29 am

I’m in favour of using the full 12K sensor and bumping up the compression rate.

You should try the Q codecs. These great overlooked floating ratios are often far more data efficient than their fixed rate counterparts.

The only time I change to 8k is if I want the faster rolling shutter time of 8k mode.

I’ve found 12k q3 usually it about an hour per terabyte. I once did an interview at Q5 and got nearly 70mins for 256gb at 12k.

Remember the data changes with focus. A wide shot with lots of detail uses a lot more data than a close up of a face.

JB
John Brawley ACS
Cinematographer
Currently - Miami
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devinpickering

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Re: Ursa 12K - Compression Options and Delivery Formats

PostWed Jan 26, 2022 3:37 am

John Brawley wrote:I’m in favour of using the full 12K sensor and bumping up the compression rate.

You should try the Q codecs. These great overlooked floating ratios are often far more data efficient than their fixed rate counterparts.

The only time I change to 8k is if I want the faster rolling shutter time of 8k mode.

I’ve found 12k q3 usually it about an hour per terabyte. I once did an interview at Q5 and got nearly 70mins for 256gb at 12k.

Remember the data changes with focus. A wide shot with lots of detail uses a lot more data than a close up of a face.

JB



That's really helpful John, thanks. What do you feel like a reasonable compression rate for 12K is? is 18:1 okay to work with or nah? And funny thing is I'm shooting all landscapes tomorrow :D
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John Brawley

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Re: Ursa 12K - Compression Options and Delivery Formats

PostWed Jan 26, 2022 5:17 am

devinpickering wrote:
John Brawley wrote:I’m in favour of using the full 12K sensor and bumping up the compression rate.

You should try the Q codecs. These great overlooked floating ratios are often far more data efficient than their fixed rate counterparts.

The only time I change to 8k is if I want the faster rolling shutter time of 8k mode.

I’ve found 12k q3 usually it about an hour per terabyte. I once did an interview at Q5 and got nearly 70mins for 256gb at 12k.

Remember the data changes with focus. A wide shot with lots of detail uses a lot more data than a close up of a face.

JB



That's really helpful John, thanks. What do you feel like a reasonable compression rate for 12K is? is 18:1 okay to work with or nah? And funny thing is I'm shooting all landscapes tomorrow :D


If it’s a lots of fine detail then it’s better to use a higher rate. So q3 for example would be a good mix of lower data rate but still enough for a more detailed scene.

When you push the compression too hard on fine detail it can mush a little. But that’s where I keep saying use the q. It’s smart enough to scale as required.

JB
John Brawley ACS
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Currently - Miami
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Uli Plank

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Re: Ursa 12K - Compression Options and Delivery Formats

PostWed Jan 26, 2022 9:54 am

But you must be sure that your media is supporting sudden spikes of high detail.
The software may be free, but the hardware needed for smooth performance is not.

Resolve Studio 17.4.6 , MacOS 12.3.1
MacBook M1 Pro, 16 GPU cores, 32 GB RAM
and
iMac 2017, Radeon 580, 32 GB RAM
Speed Editor

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