crawling out of a 3D crater
by Shane Benson
on
Nov 20, 2008 at 9:07:26 pm
My plans are to shoot some video of a field where a 3D ship has crashed, creating a crater. The crater will be 3D also. The shot will be tracked with Boujou, the 3D will be done with C4D, and the comp will be brought together in AE.
The problem ive run into, (seeing as how ive never done it before), is that I need one of the actors to crawl out of this 3D crater, but im stumped as to how to do this. I currently do not have any green screen, so that it out of the question right now.
Is there a way to do this, so that the actor will appear to crawl out of the crater?
Re: crawling out of a 3D crater by Dave LaRonde on Nov 20, 2008 at 9:44:27 pm
To do what you want without a chroma key, you'll have to use an EXTREMELY painstaking and time-consuming technique, rotoscoping.
But before you start diving into C4D, I STRONGLY suggest that you storyboard out this sequence shot by shot, so that you know precisely what you're up against.
You will be amazed at how the simple act of putting pencil to paper poses challenges to the vision in your brain, raises new questions that must be answered, and in general saves you from biting off more than you can chew.
Dave LaRonde
Sr. Promotion Producer
KCRG-TV (ABC) Cedar Rapids, IA
Re: crawling out of a 3D crater by Shane Benson on Nov 20, 2008 at 9:59:47 pm
Thanks Dave for the info. In the past, I have done tons of roto before. Usually when I didnt have a chroma key, or a premade alpha matte.
I have already created a test shot (animation) of a small crater type hole in the ground, and it worked nicely. The whole idea has not been put on paper yet, (as you suggested), but it has been discussed between myself, and my cousin who is helping and will probably be the one crawling out of the crater.
If i have to roto, then thats not a big deal. Ive done worse. The main problem is that im not sure how to shoot the footage... such as, should the actor crawl out of a real hole, or should he climb of up a wall, and then the roto'd key will be placed with the crater.
I know this will be a rather large undertaking, but im always up for a challenge, and to learn something new.
Re: crawling out of a 3D crater by Dave LaRonde on Nov 20, 2008 at 10:10:16 pm
[Shane Benson]"The main problem is that im not sure how to shoot the footage... such as, should the actor crawl out of a real hole, or should he climb of up a wall, and then the roto'd key will be placed with the crater."
Beats me. Insufficient information.
Will you see the spaceship in the background? Will there be smoke & flames? Is this shot high-angle or low-angle? Wide or tight?
The list is incomplete and just for starters. When you know, write back.
Dave LaRonde
Sr. Promotion Producer
KCRG-TV (ABC) Cedar Rapids, IA
Re: crawling out of a 3D crater by Shane Benson on Nov 20, 2008 at 10:27:54 pm
Sorry about that. I should have given more details.
The crash shot will be back from a distance.. wide shot. The next few shots (character crawling out) will contain both wide and tight.
The wide will be from several distant angles (human eye perspective), and the close up tight shots that will be taken into account will range from near ground level, or human eye level right on top of the character as he stands up after making his way out of the crater.
The spaceship (or at least the remaining debris) will be visible inside the crater. There will be some fire, and smoke rising.
If I can recall, I think I have some cheap green screen type material that ive used before. I had forgotten about it.
I can see that someone answering this question is rather difficult because all the details are not right in front of you, and without having an understanding of the shot, its hard to say.
Re: crawling out of a 3D crater by Dave LaRonde on Nov 20, 2008 at 11:09:29 pm
Well, okay, if you don't mind roto work.....
Shoot the real deal, the guy climbing out a real crater, from as many angles as you need. Don't forget to shoo a clean plate for each. Do it on a locked-down camera to make life easier.
Dave LaRonde
Sr. Promotion Producer
KCRG-TV (ABC) Cedar Rapids, IA
Re: crawling out of a 3D crater by Alejandro Ortiz on Nov 21, 2008 at 12:11:05 am
You might want to check Andrew Kramer's tutorial series on creating a 3d crater. It's done in AFX and 3dsmax but the principles are the same in any 3d app. http://www.videocopilot.net/tutorials/3d_crater_p1/ Judging by the description of your project you might be surprised of how these tuts approach pretty much what you're aiming at.
Re: crawling out of a 3D crater by Shane Benson on Nov 21, 2008 at 3:40:44 am
Thats funny you mention it, because I had got the idea from that tutorial, but wanted to do more with it. Andrew's tutorial was based on a character walking around the debris, but I wanted to do more, plus it would go along with the video ill be shooting.
Ive already made a small test animation that I tracked with a small version of a crater in some footage, and it turned out quite nice.
As far as the original question concerning how I should shoot it... I think what im going to do is set up a table (or something sturdy) covered with green screen and film the actor climbing up onto the table. Then use that for the crater shot.
Re: crawling out of a 3D crater by Dave LaRonde on Nov 21, 2008 at 4:58:07 pm
[Shane Benson]"...we dont have a real crater to use"
Okay, then how do you propose to make it look like the guy's climbing out of one? How do you make it look like he's stumbling down the sloped sides if you don't have sloped sides?
What you want to do ain't exactly child's play, y'know. And if you DO think it is, it'll look like it was done by a child.
Sorry, but them's the facts.
Dave LaRonde
Sr. Promotion Producer
KCRG-TV (ABC) Cedar Rapids, IA
Re: crawling out of a 3D crater by Shane Benson on Nov 21, 2008 at 6:41:37 pm
Well, I was speaking about the shot where the camera would be placed at the edge of the crater looking slightly downward, then have the character climb up, and onto the table while having green screen on the table, and behind the character as well.
For a wide shot showing the character making his way up the slope, on the location, there will be a embankment that we can line with green screen and use because its part of a sloped dam for a large pond. That should give us the "slope" we need.
The shots themselves arent going to be anything too entirely difficult. The camera will be locked down on a tripod.
