Best settings for chroma key? at DVinfo.net

Ryan Mueller · February 13th, 2010, 05:42 PM

Any suggestions? Should I bump down the sharpness a bit? I am shooting a ton of green screen footage this coming week.

David Chapman · February 14th, 2010, 07:16 AM

If there is distance between the screen and your subject, you can get all of the screen out of focus to get rid of any wrinkles (depending on the screen type). I wouldn't over expose. I've gotten footage from other DP's that insist on over exposing a stop. I hate this in post. Make sure there is good separation from the green and blond hair (if you have any). As long as your screen is evenly lit, you should be good. With a generic flat profile, you should be good to go.

Oh, and a low-noise ISO setting. Depending on the subject, 200/400 or 320 if you don't have a ton of highlights. Don't use highlight tone priority, though.

Ryan Mueller · February 17th, 2010, 06:51 PM

Thanks for the tips David. The shoot went well. 700 clips and I was able to build one master key templet in Keylight and it was sufficient on all clips with very minimal tweaking from clip to clip. This footage keyed much better than I initially thought it would. Very clean with fine detail.

Tim Kolb · February 18th, 2010, 08:38 AM

That's good to know. Thanks for posting after you took the footage through post Ryan.

I've not tested the 5D for composite shots (the clips I've attempted to color correct from the camera have been so difficult to push in any direction that I would have typically avoided using a DSLR for this purpose).

The latitude is incredible on these cameras, but as many have noted, the aggressive compression is a handful in post.

Anyway...thanks for the follow up post.

Matthew Roddy · February 18th, 2010, 12:10 PM

Ryan,

Did you transcode to any other codec, or did you stay native? I would have gone to Cineform, but have never tried this with keying...

Chris Barcellos · February 18th, 2010, 07:08 PM

I shot this promo within about 2 weeks of getting my 5DII. Pretty sure I used Cineform. Green screen portion shot in my garage in front of a of canvas painted green. Keyed with Vegas. I had been trying to key HDV with similar set ups for years, with crappy results. While I hads some spill in this, the keying went relatively easy.

Ryan Mueller · February 19th, 2010, 01:54 PM

I went to ProRes for the key and keyed with Keylight in AE. I'd post some samples for you, but unfortunately am bound by an NDA. The footage is not "perfect", but I think it would have been much better if the client had not built the Chroma studio themselves. I had some obstacles to work around, but the overall result is quite exceptional considering the circumstances.

February 13th, 2010, 05:42 PM	#1
Ryan Mueller Major Player Join Date: Mar 2007 Location: Highlands Ranch, CO Posts: 336	Best settings for chroma key? Any suggestions? Should I bump down the sharpness a bit? I am shooting a ton of green screen footage this coming week.

February 14th, 2010, 07:16 AM	#2
David Chapman Major Player Join Date: Mar 2006 Location: Dallas, TX Posts: 346	If there is distance between the screen and your subject, you can get all of the screen out of focus to get rid of any wrinkles (depending on the screen type). I wouldn't over expose. I've gotten footage from other DP's that insist on over exposing a stop. I hate this in post. Make sure there is good separation from the green and blond hair (if you have any). As long as your screen is evenly lit, you should be good. With a generic flat profile, you should be good to go. Oh, and a low-noise ISO setting. Depending on the subject, 200/400 or 320 if you don't have a ton of highlights. Don't use highlight tone priority, though. __________________ David Chapman www.davechapfilms.com

February 18th, 2010, 08:38 AM	#4
Tim Kolb Major Player Join Date: Mar 2005 Location: Neenah, WI Posts: 547	That's good to know. Thanks for posting after you took the footage through post Ryan. I've not tested the 5D for composite shots (the clips I've attempted to color correct from the camera have been so difficult to push in any direction that I would have typically avoided using a DSLR for this purpose). The latitude is incredible on these cameras, but as many have noted, the aggressive compression is a handful in post. Anyway...thanks for the follow up post. __________________ TimK Kolb Productions

February 18th, 2010, 07:08 PM	#6
Chris Barcellos Inner Circle Join Date: Nov 2005 Location: Elk Grove CA Posts: 6,838	I shot this promo within about 2 weeks of getting my 5DII. Pretty sure I used Cineform. Green screen portion shot in my garage in front of a of canvas painted green. Keyed with Vegas. I had been trying to key HDV with similar set ups for years, with crappy results. While I hads some spill in this, the keying went relatively easy. Sacramento Film Festival Promo Shot with Canon 5D MarkII on Vimeo __________________ Chris J. Barcellos

February 17th, 2010, 06:51 PM	#3
Ryan Mueller Major Player Join Date: Mar 2007 Location: Highlands Ranch, CO Posts: 336	Thanks for the tips David. The shoot went well. 700 clips and I was able to build one master key templet in Keylight and it was sufficient on all clips with very minimal tweaking from clip to clip. This footage keyed much better than I initially thought it would. Very clean with fine detail.

February 18th, 2010, 12:10 PM	#5
Matthew Roddy Major Player Join Date: Jan 2006 Location: Riverside, Ca Posts: 307	Ryan, Did you transcode to any other codec, or did you stay native? I would have gone to Cineform, but have never tried this with keying...

February 19th, 2010, 01:54 PM	#7
Ryan Mueller Major Player Join Date: Mar 2007 Location: Highlands Ranch, CO Posts: 336	I went to ProRes for the key and keyed with Keylight in AE. I'd post some samples for you, but unfortunately am bound by an NDA. The footage is not "perfect", but I think it would have been much better if the client had not built the Chroma studio themselves. I had some obstacles to work around, but the overall result is quite exceptional considering the circumstances.