Keying large element

[Frank Martin]

Hey guys, any help would be most appreciated. We are doing a series of spots that will require large elements to be keyed.
Such as a large boat on the water,0r a giant car hauler rig. I was curious if its possible to pull a clean key on water or if i park the truck under an overpass ( against all grey). Production company is asking questions about post costs , . All shots involve a static camera. Second question . There is a foreground ipe element that would be a lot more dynamic if we used a MOCO slider. Do you think we could marry that to a background plate that was simply zoomed in on during shot. As opposed to shooting backgrounds on slider.
Thanks in advance
Frank

 

[John Marchant]

Depending on a lot of variables of course, primarily shot length and intricacy of the key, it may well be that rotoscoping the large elements is more cost effective than finding a way of getting a chroma backdrop in place.

 

[Joel Arvidsson]

I think roto could a good solution. Not sure what an overpass is but sounds like a bridge and that the truck would get boring reflections and highlights. Whats the background going to look like? Is there any humans interacting with the truck?

 

[Frank Martin]

Thanks for your replies. Boats are on water. Big truck gets dropped in a driveway. Sounded like a rotoscope deal to me as well but thought there might be a way to pull a luminance key. . The overpass was just a thought to find a big solid backround to work with.

 

[Jimmy Gilmore]

On water, depending on subject color and position of sun, the sky should/can be fairly easy to key and then clean up manually. Red Giant or Smoke are really great with this. Water on hull may be trickyif it's choppy. Truck in driveway, without seeing the boards, a combo of a shooting with and without a green background may work. Get with your post supervisor if possible. Hope I'm being helpful.


Truck at beach at sunrise may work as well if you're already at the water.


Grey may be a bitch to key. It has no chroma value.


Also if the camera is static and the BG is keyed, why not still shoot it and photoshop it? Then composite in Smoke or AE? Again, haven't seen the boards so I'm just spitballing here.


I realize that with spots, production doesn't always talk to post but if they want to save money they ought to.


There's often more ways to accomplish things. Good luck.

 

[Craig Parkes]

Certainly sounds like rotoscoping if you have a static camera. If you are going to zoom into the objects on a slider, make sure you have plenty of tracking markers in the area of background that you will be rotoing out. That way you can get a 3D camera into your compositing program etc and you'll be able to set up the background plates to match the camera move without having to do moco.

But really, unless you are doing the post, talk to the guys doing the post and come up with a plan together.

 

[Marc Wielage]

Hey guys, any help would be most appreciated. We are doing a series of spots that will require large elements to be keyed. Such as a large boat on the water,0r a giant car hauler rig. I was curious if its possible to pull a clean key on water or if i park the truck under an overpass ( against all grey).

Bear in mind that even Peter Jackson and Weta Digital couldn't key boats very well. Check out the small boat scenes in King Kong to get an idea of the struggles they had, both in creating water and in simulating the motion of a boat on water. I don't think there are a lot of compositing challenges worse than this.