Given the choice... P4k low light at ISO 1250 ?por 3200

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marcellomazzilli

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Given the choice... P4k low light at ISO 1250 ?por 3200

PostTue Nov 20, 2018 8:25 am

Is it better to use the "native" 3200 or to shoot at lowest possible ISO (within the 3200 range) ?

Given the possibility to choose.. that is .. enough light to stop down iris and step up ISO.. or viceversa... What is the best ISO to work to? My idea is that I should just do what it is best for the lens (usually the don't perform at top at max. aperture). AM I wrong?
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Janis Lionel

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Re: Given the choice... P4k low light at ISO 1250 ?por 3200

PostTue Nov 20, 2018 10:54 am

According to the manual, 3200 (400 & 3200 are the reference points); but i haven't tested in real world.
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Philip Lipetz

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Re: Given the choice... P4k low light at ISO 1250 ?por 3200

PostTue Nov 20, 2018 12:50 pm

It depends on what you want to,prioritize. The lower part of the range preserves more shadow detail, and then uppper part of the range preserves more highlight detail.
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John Paines

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Re: Given the choice... P4k low light at ISO 1250 ?por 3200

PostTue Nov 20, 2018 1:39 pm

Philip Lipetz wrote:It depends on what you want to,prioritize. The lower part of the range preserves more shadow detail, and then uppper part of the range preserves more highlight detail.


Am still testing, but I believe that famous chart is widely misread, to mean something it's not actually saying (I think). Highlights clip at the same stop at either 1250 or 3200, or anything in between. Noise may be the only actual difference between the two after levels are matched in post.
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David Chapman

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Re: Given the choice... P4k low light at ISO 1250 ?por 3200

PostTue Nov 20, 2018 4:25 pm

From what I've seen tested online, if you have a choice to shoot at 800 or 100 ISO in the 400 ISO bank range, to just jump up to 1250 and you will notice a cleaner image. There are a couple videos on YouTube that show exposure changes at every stop, but I don't recall if there was a difference between noise levels at 1250 vs 3200.
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John Paines

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Re: Given the choice... P4k low light at ISO 1250 ?por 3200

PostTue Nov 20, 2018 4:45 pm

David Chapman wrote:From what I've seen tested online, if you have a choice to shoot at 800 or 100 ISO in the 400 ISO bank range, to just jump up to 1250 and you will notice a cleaner image. There are a couple videos on YouTube that show exposure changes at every stop, but I don't recall if there was a difference between noise levels at 1250 vs 3200.



You can't evaluate noise on youtube. And you're mixing up two different questions, by moving from one ISO circuit (100 to 1000) to another (1250 and up), without specifying underlying lighting levels and exposures.
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Rakesh Malik

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Re: Given the choice... P4k low light at ISO 1250 ?por 3200

PostTue Nov 20, 2018 4:56 pm

These cameras are ISO invariant. That means that once you select your base ISO setting, raising or lowering your ISO setting is really just adjusting your gamma curve, rather than exposure. That's another way of saying that you're adjusting the log curve that the camera uses to map data from linear light (i.e. sensor native) into its 12-bit payload.
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carlomacchiavello

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Re: Given the choice... P4k low light at ISO 1250 ?por 3200

PostTue Nov 20, 2018 6:15 pm

Rakesh Malik wrote:These cameras are ISO invariant. That means that once you select your base ISO setting, raising or lowering your ISO setting is really just adjusting your gamma curve, rather than exposure. That's another way of saying that you're adjusting the log curve that the camera uses to map data from linear light (i.e. sensor native) into its 12-bit payload.


Uhm for pocket4k no
There are two native iso or two different way to use and expose sensor, then when use first or second iso is to expose with more or less light.
From what I understand this user ask when and where is the limits on one and where start second iso or where is better to use second native iso.


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rick.lang

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Re: Given the choice... P4k low light at ISO 1250 ?por 3200

PostWed Nov 21, 2018 12:17 am

Don’t have the camera yet; but based on what we have seen, I’d recommend shooting ProRes at ISO 1250 before you shoot at ISO 3200 or ISO 1000. That’s if you have enough light and aren’t being forced to shoot at ISO 3200.
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