Any descriptions anywhere on Cinegammas?

Duke M.

Duke M.

Veteran
Here's what I usually remember about Cinegammas:

Cine1 protects highlights, goes above IRE100.

Cine2 protects highlights and blacks, stays within broadcast limits.

Cine4 is brighter.

Cine3 is similar to Cine4, but I have no real idea what Cine3 and 4 are really doing. The manual gives a really lousy description. (page 77)
 
I'm hoping this is the right one, but its slow to play.
http://blog.abelcine.com/2011/03/31/abelcine-tests-the-sony-f3-dynamic-range/

This comment by Jason Rodriguez was enlightening for its counter intuitive analysis:
"Cinegamma-4 would actually give you the most "apparent" dynamic range along with increased highlight protection as it will naturally force you to protect the highlights since midde-grey is "pushed" up by almost 1 f-stop. In other words if you were shooting a scene with a middle-grey card, and you were to look at the image on a properly calibrated monitor, middle-grey would look too "bright" with Cinegamma-4, and as a result, you would reduce the exposure in order to make middle-grey look "normal" again ... this in turn would also bring back detail in any clipped highlights, creating the appearance of more dynamic range in the highlights (the actual total dynamic range hasn't changed, but the apparent dynamic range has been biased to protect the highlights)."
 
This is from the BBC white paper.

"Descriptions in the manual seem to fit the idea that these curves are directly copied from other cameras, whereStd5=ITU709, Std6=BBC0.4; Std1 has lowest slope near black (for low noise and black-crushing); Std2 is somewherebetween Std1 and Std3. The Cine curves are not the “Hypergamma” curves of the PDW700, HDWF900R/790,SRWF9000 etc. Cine2 is the only curve suited to production without grading, since it clips at 100%. Cine1 is similarbut copes with overexposure by extending beyond 100% video level. Cine3 and 4 differently share the contrast range,use these to taste. If using Cine1 or 3, make sure that video will not be clipped in post-production. Or that grading cancope with the over-voltages.​
9​
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Black stretch (positive values) should be needed only under exceptional conditions, unless the lower-slope Std gammacurves are used, and will increase the noise level. With negative levels, black-crushing will happen, which may be asolution when operating with high video gain levels.​
10 Low Key Sat is useful when video noise levels are high, use a negative amount."


The PDF can be downloaded here http://downloads.bbc.co.uk/rd/pubs/whp/whp-pdf-files/WHP034-ADD68_Sony_PMW-F3.pdf



The PDF is nice to refer back to.


Cheers!
 
Of the Cine Gammas, only Cine2 is within broadcast limits. Cine 1, 3 and 4 are IRE109.

Definitely worth saving that PDF for future reference.
 
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