Latest thoughts on using F-350 with green screen at DVinfo.net

Jay Lee · May 1st, 2007, 07:36 PM

Now that there has been more time for the F-350 to be used, I'd like to hear the impressions of those that are keying with green/blue screen. How is it working? I'm looking at using it with presenters to do promos/turorials/corporate news, so nothing too demanding. Any gotchas? How does it compare with using a high end DV camera like a DSR-400/450?
Thanks

Alister Chapman · May 2nd, 2007, 12:52 PM

I did a big blue screen studio shoot for a client in HD. The results were very good with clean keys. There were the usual problems with fine hairs, but overall it produced a very good key. We shot 25P HD, the post production was done in HD and then we down converted to SD for the final DVD masters. Post production was a mixture of Avid and After effects.

Nate Weaver · May 2nd, 2007, 07:12 PM

I did a job on green, Bravo was the client.

Check out the open of "Shear Genius", dunno what nights it's on. We shot lots of hair flying around, all the keys came out fine and the shop that did it all reported that it was all easy.

Tyson Persall · May 15th, 2007, 04:42 PM

When you guys did your compositing, you did it with the files off the disks using XDCAM HD format right. Not a HD-SDI tethered deal right?

Greg Boston · May 15th, 2007, 08:58 PM

Quote:

Originally Posted by Tyson Persall

When you guys did your compositing, you did it with the files off the disks using XDCAM HD format right. Not a HD-SDI tethered deal right?

Tyson, 4:2:0 does much better at keying than you would think. The higher resolution of HD helps, along with shooting a progressive image. That will get you very close, and these days, software can step in and clean up pretty nicely.

-gb-

Greg Boston · May 15th, 2007, 09:00 PM

Quote:

Originally Posted by Nate Weaver

I did a job on green, Bravo was the client.

Check out the open of "Shear Genius", dunno what nights it's on. We shot lots of hair flying around, all the keys came out fine and the shop that did it all reported that it was all easy.

BTW Nate, I meant to tell you that I saw the promo for Shear Genius running on NBC last week. The keys looked very good!

-gb-

Alister Chapman · May 16th, 2007, 02:12 AM

Keying was done from the XDCAM HD MXF's transfered using FAM.

Max Kaiser · May 17th, 2007, 11:27 AM

Our only experience has been that it is MUCH better if you shoot in a P format, and not an I format. Now that we've gone through the process a few times, this makes perfect sense, but believe me - it really helps AE get through the key process.

Max

Alister Chapman · May 18th, 2007, 01:38 AM

Agreed. Progressive is the way to go. Far better key than with interlace.

Thomas Smet · May 18th, 2007, 08:17 AM

I also agree. Interlaced 4:2:0 is much worse then progressive 4:2:0. Progressive isn't really that much harder then 4:2:2. Check out the sample image I have attached that shows what the different levels of color compression can look like. Progressive 4:2:0 is really a very nice format because really the chroma samples are just 2x2 pixels in size. This can give you some very clean results because the horizontal and vertical have the same ratio of samples. If you have a tool to resample or slightly blur the two chroma channels then your results will be even better.

Note: This image was created by creating a RGB AVI file and encoding it with a mpeg2 encoder into the different formats. I then took stills from the video files and put them together in this image.

May 1st, 2007, 07:36 PM	#1
Jay Lee Regular Crew Join Date: Feb 2006 Posts: 57	Latest thoughts on using F-350 with green screen Now that there has been more time for the F-350 to be used, I'd like to hear the impressions of those that are keying with green/blue screen. How is it working? I'm looking at using it with presenters to do promos/turorials/corporate news, so nothing too demanding. Any gotchas? How does it compare with using a high end DV camera like a DSR-400/450? Thanks

May 2nd, 2007, 12:52 PM	#2
Alister Chapman Inner Circle Join Date: Dec 2005 Location: Bracknell, Berkshire, UK Posts: 4,957	I did a big blue screen studio shoot for a client in HD. The results were very good with clean keys. There were the usual problems with fine hairs, but overall it produced a very good key. We shot 25P HD, the post production was done in HD and then we down converted to SD for the final DVD masters. Post production was a mixture of Avid and After effects. __________________ Alister Chapman, Film-Maker/Stormchaser http://www.xdcam-user.com/alisters-blog/ My XDCAM site and blog. http://www.hurricane-rig.com

May 2nd, 2007, 07:12 PM	#3
Nate Weaver Wrangler Join Date: Oct 2002 Location: Los Angeles, CA Posts: 2,100	I did a job on green, Bravo was the client. Check out the open of "Shear Genius", dunno what nights it's on. We shot lots of hair flying around, all the keys came out fine and the shop that did it all reported that it was all easy. __________________ My Work: nateweaver.net

May 15th, 2007, 04:42 PM	#4
Tyson Persall Major Player Join Date: Sep 2004 Location: North Hollywood, Atlanta Posts: 437	HD-SDI output for greenscreen When you guys did your compositing, you did it with the files off the disks using XDCAM HD format right. Not a HD-SDI tethered deal right? __________________ Tyson X

May 16th, 2007, 02:12 AM	#7
Alister Chapman Inner Circle Join Date: Dec 2005 Location: Bracknell, Berkshire, UK Posts: 4,957	Keying was done from the XDCAM HD MXF's transfered using FAM. __________________ Alister Chapman, Film-Maker/Stormchaser http://www.xdcam-user.com/alisters-blog/ My XDCAM site and blog. http://www.hurricane-rig.com

May 17th, 2007, 11:27 AM	#8
Max Kaiser Regular Crew Join Date: May 2005 Location: Bellingham, WA Posts: 66	Our only experience has been that it is MUCH better if you shoot in a P format, and not an I format. Now that we've gone through the process a few times, this makes perfect sense, but believe me - it really helps AE get through the key process. Max __________________ ---------------- Max Kaiser Director, Hand Crank Films http://www.handcrankfilms.com

May 18th, 2007, 01:38 AM	#9
Alister Chapman Inner Circle Join Date: Dec 2005 Location: Bracknell, Berkshire, UK Posts: 4,957	Agreed. Progressive is the way to go. Far better key than with interlace. __________________ Alister Chapman, Film-Maker/Stormchaser http://www.xdcam-user.com/alisters-blog/ My XDCAM site and blog. http://www.hurricane-rig.com

May 18th, 2007, 08:17 AM	#10
Thomas Smet Trustee Join Date: Mar 2004 Location: Milwaukee, WI Posts: 1,719	I also agree. Interlaced 4:2:0 is much worse then progressive 4:2:0. Progressive isn't really that much harder then 4:2:2. Check out the sample image I have attached that shows what the different levels of color compression can look like. Progressive 4:2:0 is really a very nice format because really the chroma samples are just 2x2 pixels in size. This can give you some very clean results because the horizontal and vertical have the same ratio of samples. If you have a tool to resample or slightly blur the two chroma channels then your results will be even better. Note: This image was created by creating a RGB AVI file and encoding it with a mpeg2 encoder into the different formats. I then took stills from the video files and put them together in this image. Attached Thumbnails