Digital Cinema Dynamic Range, Short Version

Here's another way to put it:

Shooting with RED One rated at its native sensitivity and monitoring Rec709, if you put 18% gray at 45% IRE, you'll capture 2 stops over 18% gray, plus some headroom.

If you underexpose from there by 1 stop, you'll capture 3 stops over 18% gray, plus a little headroom.

Underexpose by 2 stops, you get 4 stops over 18% gray, plus headroom.

Want to match Panalog? Underexpose by 3 stops for 5 stops over 18% gray, plus headroom.

Want to match a hypothetical "perfect" film stock? Underexpose by 4 stops to match the Cineon spec's 6 stops over 18% gray... you guessed it, plus some headroom.

And then put the results into your grading system and see if the noise levels on your gray card are acceptable.

This is what I'd do if I had a RED One, a pretty girl, and a window!

EDIT 080223: I added the italic text at the top in response to David Mullen's post on the reduser.net thread that's been running parallel with these posts.

Comments

[mikehedge]

totally great ideas.

thanks.

mike
RED #998

[Dale McCready]

Great stuff Stu,

I guess it all comes down to the shadows then and whether too much detail is lost down there and too much noise brought up later if the output switches to a more vid look.

test test test. Now to find the pretty girl

[Ben Grossmann]

Sweet. I actually did that on a scene I measured to have 10 stops of dynamic range (With my trusty old Sekonic spotmeter). What I found was that if I rated the Red at the recommended 320ASA I was doing fine. If I rated it even a half stop more at 500ASA shadow detail started dropping off a cliff and was awash with the compression.

A full stop was pretty unacceptable. As far as I'm concerned, you've gotta shoot the Red "to the right" on the histogram until they come up with a way to cut that compression down, or record to a Codex or some such.