View Full Version : Latest thoughts on using F-350 with green screen


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
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
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.