Shooting with a 4k and a 6k

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antioli

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Shooting with a 4k and a 6k

PostMon Sep 26, 2022 7:02 pm

The first image is from a 6k (shooting 4k) using an EF lens.
And the second is from a 4k using a micro four third lens.

Both have the same settings (iso 3200, 180 shutter angle, same bitrate, same everythihng etc...) and are wide open or close to. One is Gen 4 one is Gen 5 but that's about it.

Why is the 6k so much more grainy?
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carlomacchiavello

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Re: Shooting with a 4k and a 6k

PostMon Sep 26, 2022 7:59 pm

How be when you move all to gen 5 and develop with aces or Rcm?

You see two cameras with first 4K with more contrast log, second with more flat log. You should see final result on final resolution.

I had for many years both, at end of chain you have same result, with 6k a bit clean picture at end of chain thanks to down sampling from 6k to 4K picture.

6k can have a bit of more noise than 4K due smaller pixel of s35 6k sensor, but you should see the end result.


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antioli

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Re: Shooting with a 4k and a 6k

PostMon Sep 26, 2022 8:31 pm

Once they are all in an ACES color space the noise gap is still noticeable on a lot of shots

I can't change the 4k to Gen 5 but I can change the 6k to Gen 4 and the grain is still there.

I understand that the grain is a little more noticeable due to the higher resolution but it seems like way too much grain.

Here's another example. Same settings again, now in ACES. Top is the 4k, bottom is the 6k.

Grainier AND darker!
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Jamie LeJeune

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Re: Shooting with a 4k and a 6k

PostMon Sep 26, 2022 9:04 pm

Different lenses, right? Were they set to the same T-stop? Or were they only marked in F-stops?
F-Stop is a calculation based on the focal length of the lens relative to size of the aperture, while a T-Stop represents the actual measurement of light transmitted through the lens.
So, if the lenses are only set to the same F-stop, that doesn't mean they are delivering the same amount of light to the sensor.
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ShaheedMalik

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Re: Shooting with a 4k and a 6k

PostTue Sep 27, 2022 5:38 am

Gen 4 had a more of Rec 709 image.

Why can't you put it on Gen 5?

What lenses are you using?

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