Ursa 4.6k G2 middle gray placements

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rNeil H

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Ursa 4.6k G2 middle gray placements

PostTue Jun 04, 2024 6:05 am

Just got the beast, and I'm looking at the chart for highlights versus shadows relative to middle gray. It looks odd to me.

ISO 200 has 3.9 stops above MG, 10.8 under?

Given that "middle gray" is about Zone IV in the Adam's system, and in everything else, why nearly 11 stops below that?

For a camera supposedly so good with high dynamic range and highlight control, you don't even get to about even distribution until ISO 2000.

I'd love some education on planning exposure with this camera. And note, I've been using incident and spot meters and flash meters for 40 some years professionally. I want solid technical advice.

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Ellory Yu

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Re: Ursa 4.6k G2 middle gray placements

PostTue Jun 04, 2024 7:25 am

URSA Mini Pro 4.6K G2, BMPCC 6K. iMac Pro 27” 5K Retina, 64gb, 1Tb SSD, 12Tb M.2 NVMe TB4 DAS, 36Tb HDD DAS, Vega 56 8gb GPU/ BM Vega 56 8gb eGPU, MacOS Sequoia+DVRS 19.1.4, BM Panel & Speed Editor. Mac Mini M2 Pro 10/16 cores, Sequoia+DVRS 20

Michel Rabe

Re: Ursa 4.6k G2 middle gray placements

PostTue Jun 04, 2024 10:45 am

Ellory Yu wrote:See page 37 of this manual.
https://documents.blackmagicdesign.com/ ... 1714810000


He obviously already has that information.
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rick.lang

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Re: Ursa 4.6k G2 middle gray placements

PostTue Jun 04, 2024 4:06 pm

That camera should be exposed for and set at ISO 800, not 200. You should see a different distribution of stops above and below middle grey.
Rick Lang
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ShaheedMalik

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Re: Ursa 4.6k G2 middle gray placements

PostTue Jun 04, 2024 4:21 pm

Is ISO 800 the native ISO?
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rick.lang

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Ursa 4.6k G2 middle gray placements

PostTue Jun 04, 2024 4:24 pm

That’s my understanding. It is ISO 800 on the URSA Mini 4.6K and I thought that rating was continued with the Pro versions of the 4.6K sensors.
Last edited by rick.lang on Tue Jun 04, 2024 6:23 pm, edited 1 time in total.
Rick Lang
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Ellory Yu

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Re: Ursa 4.6k G2 middle gray placements

PostTue Jun 04, 2024 6:21 pm

Michel Rabe wrote:
Ellory Yu wrote:See page 37 of this manual.
https://documents.blackmagicdesign.com/ ... 1714810000


He obviously already has that information.

Well good if he did coz he only said chart. There are other charts in the wild and I don’t know what he was referring to specifically. Glad you can read minds (or between the lines). :lol: moving on…
URSA Mini Pro 4.6K G2, BMPCC 6K. iMac Pro 27” 5K Retina, 64gb, 1Tb SSD, 12Tb M.2 NVMe TB4 DAS, 36Tb HDD DAS, Vega 56 8gb GPU/ BM Vega 56 8gb eGPU, MacOS Sequoia+DVRS 19.1.4, BM Panel & Speed Editor. Mac Mini M2 Pro 10/16 cores, Sequoia+DVRS 20
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rNeil H

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Re: Ursa 4.6k G2 middle gray placements

PostTue Jun 04, 2024 9:42 pm

Those are clearly the specific numbers from the chart in the manual. Like, duh?

Thanks to Ric for adding at least a useful suggestion. Though I would love any further, technically sound information and advice from the users here.

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Howard Roll

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Re: Ursa 4.6k G2 middle gray placements

PostWed Jun 05, 2024 5:14 am

Consider for a moment that the aspirational 15 stops listed in the manual are more like 13+. The “native” ISO of 800 is more realistically like 6 over, 7+ under. For digital cameras stops above middle grey are easily defined, below mid grey it’s more subjective.

Good Luck
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rNeil H

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Re: Ursa 4.6k G2 middle gray placements

PostWed Jun 05, 2024 6:54 am

Thanks, Howard. Yea, I never assume the outer listed capabilities are perhaps as usable as one might prefer. Test everything, right?

It just seems weird that so much of the data is supposedly below MG. Compared to that above.

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