View Full Version : S-Log / Green Screen - Suggestions?


Dave Sperling
March 8th, 2012, 06:41 PM
Hi,
Anyone out there shooting green screen stuff to S-Log?
I may have some coming up for a shoot, and though I do intend to do some testing, it would be great to hear from anyone who's been doing it already.
Specifically, wondering what IRE levels you're targeting for the green screen and for caucasian skin tones.
Also, whether you prefer to go tungsten balance or daylight (with the appropriate lights of course).
And whether you find that increasing the green chroma with gels is helpful.
Thanks!
- Dave Sperling

Chris Medico
March 8th, 2012, 06:44 PM
Might sound like an odd question but why do you need S-Log in a controlled lighting situation such as a green screen set?

Douglas Villalba
March 8th, 2012, 07:09 PM
I agree with Chris. You would have to grade before you pull a key.
On a side note, I've only done one chroma job and I'm not very happy with the results. I used 5400k lights recorded to PR HQ. I have gotten better keys from a canon dslr.
I have to do more test 'cause it really doesn't make any sense.

Dave Sperling
March 8th, 2012, 08:05 PM
Might sound like an odd question but why do you need S-Log in a controlled lighting situation such as a green screen set?

It's a project in which there are about a dozen green screen shots that would be interspersed amongst about 800 shots. Everything will go through a DI process at the end, which is where the final mattes would be pulled .

A few of the foreground shots may have elements where I'd like the increased dynamic range.

And of course since everything else will be S-Log, my current thinking is that the green screen foreground elements may match better with their S-Log background plates, as well as with the non-composited shots in the scene.

Sounds like I should shoot several variations to test with.... (Looking at it in the post facility's DI room)

Chris Medico
March 8th, 2012, 08:23 PM
You shouldn't need to shoot s-log for the green screen work. Even with foreground objects. I can't imagine anything that needs that kind of DR. If you do I would revisit your lighting plan.

Now 10bit 4:2:2 or 4:4:4 (non s-log) would be a good thing.

Bruce Schultz
March 9th, 2012, 01:42 PM
The need to use S-Log for increased DR on a very controlled green screen shoot seems like overkill to me also. I recently did an F3/Alura 18-80mm shoot on stage at Sony Studios and used the straight REC709 settings with superb results. We had various foreground and background elements which were no problem to resolve in that setting. We recorded out to 10-bit on a Samurai and Pix240 which post production loved.

I have also shot some green screen using S-Log on in the camera, but setting the LUT to HG40 or HG33 and recording that will give you a very comparable S-Log DR without the need to grade before compositing. I would recommend testing first though.

Charles Papert
March 9th, 2012, 02:15 PM
I can see the logic of a fully-controlled green screen shoot being shot out of s-log--I guess. But of course many times green screen elements are shot within a given scene (i.e. bring in the greenscreen to shoot an element) and of course then one would want to keep the camera settings the same to make things easier in post.