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halfworld
02-07-2006, 05:37 PM
Hey all, my turn to challenge you.

So, your client has requested you animate two cars travelling in opposite directions, the camera is at right angles to the car path. You need to focus in on one car, then switch to the other before they pass. A specific request is that the camera have a hand-held feel to it.

You may use any tools available.

How would you tackle this problem?
This challenge will be moved to the Techniques and WIPs Lab once it gets going, have fun!!!
:beer:
Ian

Vizfizz
02-07-2006, 05:48 PM
Classic.

Lets put a slight spin on this, from a cinematography point of view. Car A is speeding towards Car B. The camera is traveling with Car A, perhaps off the right side and to the rear, looking forward to Car B. The speed is tremendous. As the two cars vear off from one another as they pass, the camera whip pans to follow Car B. The camera detaches from Car A and comes to a halt as it watches Car B receed in the distance.

This is an exercise in constraint systems, XP and cinematography. Use XP to construct a shakey cam feeling. Timing on the whip pan is critical.

halfworld
02-07-2006, 10:01 PM
That's more like it :)

I was late for a dinner booking hence I rushed the post ;)

There are 3 ways I can think of to do this... I wonder if our resident XP expert CJ browses this forum?
Ian

sacslacker
02-07-2006, 11:16 PM
Just a noob question here. Often times in Maya (sorry to keep mentioning Maya) I'll use a procedural noise map for my camera shake rather than mel. Is that possible with EI? I really like this technique and it saves me a bunch of time. Of course I've also used some mel to randomize keyframes in the graph editor but I'd really like the ability to animate the frequency or gain on the noise to make some neat effects real easily.

By the way, EI is sitting on my doorstep as we speak. Tonight starts my intro into EI. I know it's going to be a blast.

Vizfizz
02-07-2006, 11:45 PM
Brian...

Tell me about your technique in Maya. I typically use MEL to apply random shake to the camera and tie it into a set driven key to allow me to animate frequency and amplitude.

In EI there are a couple of ways to accomplish camera shake. One way is a built in function provided by the program to randomize values on any specific channel, but there's no way to dial that up or down with key frames. You type in a randomization value and a seed and it proceeds to apply shake to that channel. If you want more, you have to "reset" the frames and apply a new randomization value.. or select the specific cell values you want to randomize again and reapply. Xpressionist, our built in scripting tool, can be used to write an expression to randomize the position of the camera, but I don't want to steal away Ian's thunder here. So we'll wait for him to share.

Cameras in EI are always 2 node cameras. For a single node camera, you'd just parent it to a null and animate the null. Nice thing that you'll appreciate in EI is all animation paths are bezier splines. Easy to see, easy to manipulate.

EI still uses some old world thought processes in controlling channel data. There is no such thing as the hypergraph or hypershade so nodal based methodology hasn't reached us yet. The material system is still very nice and has a lot of internal capability for layering and compositing. There are a number of shaders that take advantage of this.

In Maya there are a number of methods of routing channel data into other objects. In EI, Xpressionist and constraints are your primary choice.

sacslacker
02-08-2006, 03:45 AM
Sure thing,
What I do in Maya is group the camera. On the groups translation attributes in the attribute editor I'll add a fractal texture to one or more of the translation channels (right click, create texture). Then I basically adjust the fractal from there. A couple things you have to do on the fractal is make it animated and put an expresion in the time attribute of the fractal, something like =time/15. It's pretty cool for putting a camera shake on the camera when you don't need serious control over it.

I picked this technique up somewhere (lord knows where) so I can't really call it my own but I've found it to be quite handy!

By the way I've opened up EI for the first time about 30 minutes ago, currently running through the hotkeys and getting familiar with the interface. I hope I can catch on enough to participate in these techniques. It's most likely going to take some time.

Hello EI, my name is Brian, would you please tell me how to add a shader to an object? Ha! Total noob power.

halfworld
02-08-2006, 02:14 PM
Okay, I'm going to assume that people are avoiding this because we're telling them to use XP. It really isn't that scary!

So, I've started you off, there is an explanation inside the XP plug-in interface.

XP handeld movement example (http://homepage.mac.com/cake_or_death/XP.zip)

Download, dissect, play, resect, animate, post.
Ian

AzOne
02-08-2006, 02:42 PM
Thanks for the sample file, Ian.

Every week I tell myself I should sit down and figure out XP...and everytime I find an excuse not to...maybe I'll start this weekend ;)

Aziz.

richardjoly
02-23-2006, 05:25 AM
Forgot to post this...
First try with no constraint. Only camera following the car with randomized position.
I don't beleive a second try will come soon... No time to study expressionist before the end of the Phoenix challenge...!

http://www.rdn.qc.ca/free/Project shake.mov

halfworld
02-23-2006, 06:44 AM
Very cool!

Thanks for having a go! I like it, for a first try it's great!
No XP though eh, well, I'll try to do one tonight but work is about to get very busy, and, as of Saturday I'm shifting my belongings between houses, so, I know how you feel!

As ever, nice work :)
Ian

halfworld
03-03-2006, 09:50 PM
Well here are two examples of XP driven hand held cam simulation...

External car: http://homepage.mac.com/cake_or_death/carexternal.mp4

Internal car: http://homepage.mac.com/cake_or_death/carinternal.mp4
(the same camera but inside the car, phong render).

I am not happy with the camera movement (it looks at the floor when rotating for example). This could be fixed but I really want to start on my challenge entry, I may revisit this in the future though...

There are two keyframes in the entire project, so practically all motion is controlled by XP.
Ian

richardjoly
03-04-2006, 01:30 AM
Excellent! Your cameraman is startled by the car and points the camera to the ground!
Very convincing... :p I like the movement from inside the car. After the competition I will have my first look into XP using your scripts. Nice work.

halfworld
03-04-2006, 07:34 AM
:)
Aye, I'll substitute the cars for models that won't get me sued, and then post the project a little later on for people to dissect.

Ian

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