[Cin] Trying to understand colour, try N!

[Andrew Randrianasulu]

вт, 7 нояб. 2023 г., 18:32 Andrew Randrianasulu <randrianasulu at gmail.com>:

>
>
> вт, 7 нояб. 2023 г., 18:13 Andrew Randrianasulu <randrianasulu at gmail.com>:
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>>
>> https://blender.stackexchange.com/questions/46825/render-with-a-wider-dynamic-range-in-cycles-to-produce-photorealistic-looking-im
>>
>>
>> well, this one says EXR can hold quite a big value per channel, way above
>> 1.0f, obviously.  But for displaying (and encoding?) it must be compressed
>> back to device-specific 0 - 1.0 range.
>>
>> Thing is, if I open exr example file in gimp 2.10 and re-export it - it
>> retain its above 100% values. It does not do this if I do this same
>> roundtrip via cingg. So yea, we seems to be clamping at output.
>>
>
> and this article about Premiere tries to explain Scopes, and especially
> floating point vs 8bit input - Premiere apparently can limit this setting
> for scopes themselves....
>
> https://blog.frame.io/2017/09/27/introduction-to-video-scopes/
>
>
> so, HDR as used in ultra HD need some scope that goes to 10.000 (so,
> logarithmic I guess ...)!
>
> something we should write somewhere in TODO, I guess .....
>

second technique about dealing with too shadowy video:

https://larryjordan.com/articles/premiere-pro-two-options-to-control-sdr-video-black-levels/

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*A CREATIVE USE OF BLEND MODES*

This tip was suggested by *FoodShipNine*.

If all you want to do is control black levels, but let highlights float –
which would apply to most web videos – here’s an option.

   - Using *File > New > Black Video*, create a new video clip. This
   contains a single color – black – with a video level of 0 IRE.
   - Place it above all clips in the timeline, similar in concept to an
   adjustment layer.


   - Select the black video clip then, in *Effect Controls*, set *Opacity >
   Blend Mode* to *Lighten*. This sets all pixel grayscale values in all
   clips below the black video clip to whichever is lighter, the black video
   clip or the video itself.

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so, if we does not have this mode we probably should :)



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>>
>> Still not sure where, may be in fader? (where fade can't be more than
>> 100%) . May be its time to ask Lion (Adam).
>>
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