Nowadays the useful software of stop motion animation such as Dragonframe has made the environment for shooting with one camera . But, until a while ago, There are 2 cameras for shootin. First camera is used for taking a picture for editing. The second camera is used for checking the animation. It called video asist system. Although it is a rare case, video asist system is used. So I would like to introduce it easily.
In the case of a type of camera that can not output a live video, such as the film camera, Set the second camera near the first camera. And shooting with the photos from second camera.
The process is, first move the shooting object, and shoot one frame with the first camera, and then shoot one frame with the second camera. So, once you move it, record with each camera. After shooting is completed, use the photo data with the first camera for editing, and discard the data recorded with the second camera.
The disadvantage of this method is recorded by the second camera, the angle changes and it is impossible to grasp the exact position. If you do not want to change the angle by all means, set the second camera infront of the viewfinder of the first camera, but there is another problem that the picture quality becomes considerably worse. Still, in the past, it was a few steps better than nothing.
Actually we do similar situation sometimes.
In the case, there are live-action cut with a human actor and a cut with a stop motion character. It might be used movie camera
that is not compatible with the software like Dragonframe.
In such a case, live video be separated from the movie camera, and input the computer installed software via the converter.
The converter uses Blackmagic’s Intensity etc.
The process is, first move the shooting object, and record about a few seconds with the movie camera, Next, shoot one frame with a PC. Repeat this work and advance shooting. After taking a picture, extract one frame from every recorded movie and connect by editing. captured image data by the PC will be discarded when shooting is over.
Although it is a rare case like this, but the concept of video assist system may still be necessary.