How to speed up path of a flying spear?

I’m trying to animate a scene of a spear flying into a wall in a live action comp. Here’s a still to give you an idea of what I mean- http://dl.dropbox.com/u/3985740/Blender/Capture2.PNG
I’m having trouble getting the spear to fly smoothly into the wall while maintaining speed. I have to animate it to fly into the wall in the space of three frames for the speed to look right. If I try animating it over 12 frames for a smooth path, the spear moves very slowly. I’ve tried speeding it up with the Graph Editor, but this just seems to reduce the frames, and it looks jerky again. Also, I have to render at 24 fps to match the video footage. I’m new to animating so I’m probably missing a very simple step. Help would be appreciated, thanks.

Ok, to start with I went ahead and looked up a good starting speed for a thrown javelin - turns out olympians top out around 120 fps. The visible area of the spear in the picture is about 2 feet long, so it would cross that section in less than 1 frame (which is obviously too fast.)

The only way to get the speed necessary for this shot would be to both slow the spear down a little, and add motion blur. In 2.58 motion blur is listed in the render menu as “sampled motion blur” The more samples, the more blur, the smoother it’ll look while it’s moving, but the longer your renders will take.

I’d go with the 3 -5 frames for actual impact, give the end a little quiver using a Lattice Modifier (javelins are actually quite flexible in real life) for an additional 8-10 frames so the whole impact should be done in under 1 second. The motion blur is probably going to be the biggest contributer to a smooth - realistic looking animation.

And while I’m at it, The spec on the wood part of the spear is really plastic-y, but the metal looks pretty decent. The shadow on the spear seems a little off as well, are shadows turned on for your lights?

Hope that helps :wink:

Wow, super helpful, thanks!

blur great, do u really ask abou the spear? what is you idea of the real one?

Wait, what shadow on my spear are you talking about?

Another option for bluring is Vector Blur.

Node Editor > Add > Filter > Vector Blur

In the Layers properties be sure to check the Vector box under Passes: