Where do I begin?

Nick Harris · September 22, 2009

Hi there!

I'm in pre production on a commercial that's set to shoot in a couple weeks. I've never worked with compositing outside of some minor green screen work, and we have a subtle effect that's got me a little stumped. At the end of the commercial, our principle picks up a cherry ball (about the same size or slightly larger than a bowling ball) and kicks it. Rather than sailing into the air, it explodes right on his foot.

I'm wondering what sort of methods are available for me to composite, what should I shoot in regards to background plates? Do I have the actor kick the ball, then do one with no ball, and then a clean plate? Do I shoot green screen of the ball exploding in an exact frame match from the location footage? Is this the sort of thing that's best left to CG?

Does anyone know of any reasonably priced effects houses in town (I'm in Burbank) that might be able to help me out?

Thanks a ton!

-Nick Harris

www.sunspot-pictures.com

james mcpherson · September 22, 2009

hiya

i guess you could do a 3d takeover of the ball exploding , youd need the various set info such as the distance of the ball from the camera its dimensions, angle its filmed at height from the ground type of lens used and one of those mirror ball things to show the lighting so you can match things up like positioning lighting etc in maya or a similar app

it might be hassle to line up a practical effect plate of the ball exploding not to mention rigging a ball to explode you could try going down that route anything you can do practically is always better if your going for realism. just make sure you shoot it from the same angle on a locked off camera same distance same lighting etc

if your removing the ball just shoot one plate with the actor kicking nothing(the cleanplate) and one plate of him kicking the ball (your original) and make sure they are both lit the same and the camera is locked off and try and get the actor to be as careful as possible to replicate the same moves. do a few takes to be sure you have a similar action and choose the best one , when it comes to removing the ball you may have to do a bit of warping or cheating to get the two to match up but if its a fairly fast bit of footage youll get away with it , just work on the principle that your trying to get your cleanplate to match the original as closely as possible and make the patch your replacing as small as possible to keep the original detail of the plate in there .

hope that helps

j

Hi there!

I'm in pre production on a commercial that's set to shoot in a couple weeks. I've never worked with compositing outside of some minor green screen work, and we have a subtle effect that's got me a little stumped. At the end of the commercial, our principle picks up a cherry ball (about the same size or slightly larger than a bowling ball) and kicks it. Rather than sailing into the air, it explodes right on his foot.

I'm wondering what sort of methods are available for me to composite, what should I shoot in regards to background plates? Do I have the actor kick the ball, then do one with no ball, and then a clean plate? Do I shoot green screen of the ball exploding in an exact frame match from the location footage? Is this the sort of thing that's best left to CG?

Does anyone know of any reasonably priced effects houses in town (I'm in Burbank) that might be able to help me out?

Thanks a ton!

-Nick Harris

www.sunspot-pictures.com

Tim Holtermann · September 22, 2009

James had some good advice and I would add that it would be worth shooting a clean plate without the actor at all as well. Sometimes you need to regain background that might not be there if the actor is in the way - especially if you need to roto anything, reposition, etc.

You might also want to shoot a take with the ball painted green. With a good key you could remove most of your ball and replace it with a clean plate of the actor and/or a combination of clean actor plate and plate without the actor. Then composite in your practical exploding ball or 3D element.

Hope that helps, let us know how it goes.