Please add more zebra values for exposure

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Felix Steinhardt

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  • Location: Karlsruhe / Germany

Please add more zebra values for exposure

PostSat May 04, 2013 1:24 pm

Ho,

I´d like to use Prores more often and it´s a real problem to expose correctly because ETTR doesn´t work as good as in RAW. Please just give us Zebras from 40% instead of 75% so we can expose for a greycard.

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Felix
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Peter J. DeCrescenzo

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  • Location: Portland, Oregon USA

Re: Please add more zebra values for exposure

PostSat May 04, 2013 1:51 pm

If in fact BMCC zebras are displaying IRE values when the camera is in ProRes/DNxHD recording mode, then yes, I'd like the zebra range extended down to 40% or so, too.

When the BMCC is in RAW recording mode, my understanding is that zebras display sensor clipping, not IRE values.

If instead they are IRE zebras for ProRes/DNxHD, then one of the uses I'd have for zebra values down around 50%-60% or so is for adjusting lighting for a green screen. With other cameras, setting IRE zebras in that range for exposing the green screen to get a nice even display of 50%-60% zebras usually works well for me. Once the green screen lighting is done, I then set IRE zebras to around 70% to judge exposure for skin as per usual.

Related question: Does the BMCC have to be in ProRes/DNxHD mode using "Video" (Rec. 709) (instead of "Film" [log]) gamma for zebras to display IRE values?

However, if BMCC zebras never display IRE values, but only sensor clipping, then never mind. ;-)

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Nick Vega

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Re: Please add more zebra values for exposure

PostSat May 04, 2013 2:10 pm

I'm pretty sure zebras for prores/dnxhd is also just for sensor clipping.

From the shots I took around D.C this week (all shot prores @ film log), any zebras I allowed in the shots had no recovery in Davinci.
http://vimeo.com/nickvega

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