Peter Kopala wrote:
Hi, I am doing stop motion. And need to found out how to do a certain thing with photoshop. I know you can do this, but don’t know how. Wut i want to do is make an object fly, Well from what I read, what you need to is take a picture with ur camera still, then take another one with the camera unmoved with the object plus what ever it is attached (wire) to apear floating. From this I heard by using the picture with out anything in it, u can erase the wire in the second picture without making it white, but when you erase it, you will see what would actually be being the wire if the wire wasnt there. Can anyone help?
After re-reading your post, I realized that use of the clone tool alone is not sufficient for stop motion, if the background is complex you’ll get moving artifacts where the wires were cloned over.
So yes, the technique as you describe would generally need two images – one showing the area behind the wires exactly as it needs to appear in the final stopmotion. The simplest method would be to combine the two images as layers, with the wire version in front, and then use the eraser to remove the wires, revealing the wire-free background behind them. Or put the background image on top, and use a layer mask to superimpose the area needed to remove the wires. Using a mask has the advantage that you may copy and paste the background layer over the next image and you only have to clean up the places that have changed, or move the mask layer to track the object. This is the reason, BTW, that the alpha channel was invented.
If you are using Premiere, and the camera is not moving much, export multiple (as many as your system’s memory will hold) frames from the movie at a time as a filmstrip, and process all the frames on a single image.
By this method, you’ll need to yank your suspended object out of every other frame as the camera moves, or recreate the camera movement exactly later on. If you can do that, and the animated object is not interracting significantly with objects in the background, you may be able to save some work by using a blue or green screen instead. To do this, shoot your moving object against the screen, then duplicate the camera moves for the background shot. Now all you need to do is clone out the wires, and then matte your moving object against the background. With luck and a little lighting, you may be able to physically paint out the wires to match the screen color. If you do several layers of this, move over George Lucas! —
Mike Russell
www.curvemeister.com
www.geigy.2y.net