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
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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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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.
Now that the cat #19 is out of the bag, test it as much as you can and use the subforum.

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