Now that I have the 3D rig, I need to test it.
First, there is the issue of the focal length, then the issue of the convergence. Both depend on the distance between the cameras and the subject. I am working close up, so the third issue of the separation of the cameras is moot, as I have it set to the minimum possible of 3"(one camera is upside down, and the cameras almost touch).
One advantage of the Canons S110 is that the lens ring can be set to control focal length with preset "clicks" at 24, 28, 35, 50, 85, 100 and 120 mm. That makes it much easier than using the zoom buttons on the G12. I set the Aperture at f8 in Manual mode for maximum depth of field, and only adjust the exposure.
In movie mode, I can choose the focal length, and I can correct the exposure of the image(which always seems to be washed out) and lock it. I cannot unfortunately choose aperture and speed manually.
I had to fiddle with the convergence to avoid window violation and to keep the left and right images lined up, so they don't have to be moved sideways later causing cropping on both sides.
After running the video though Premiere to sharpen, increase contrast and color saturation, the results are actually pretty good, as shown in this side by side 3D short clip shot at a focal length of 35mm. I like the way the arm extends out in front of the window as the camera gets closer to the subjects, but it is almost too much, depending on how far one is from the screen. That is one of the problems of 3D: the further away one is from the screen, the more depth the image has.
I repeated the same test with a 50mm focal length.
One other problem visible at the beginning of this video is that the further back in the window the subject is, the further apart the two images are, and that requires the eyes to diverge quite a bit. That is more difficult that having them converge, which is the case when objects are in front of the window. Objects on the window plane have almost no separation.
Therefore, it seems best to keep the main subject fairly close behind the window. Objects that entirely fit in the window can be floating in front of it, as well as protrusions(like an extended arm, a stick, etc...).
It is also better to dolly out from a close up to a mid shot, with the convergence set for the close up(the main subject images almost line up). That way, it is easier for the eyes to diverge following the images as they separate and the subject recedes deeper into the window.
Here is another test video dolly shot with the focal length set at a longer 85mm. The camera then goes from 22" to 48" from the subject. The lenses being 3" apart, we are still very far from the 1/30 rule, and the perspective is exaggerated, but it somehow works.
First, there is the issue of the focal length, then the issue of the convergence. Both depend on the distance between the cameras and the subject. I am working close up, so the third issue of the separation of the cameras is moot, as I have it set to the minimum possible of 3"(one camera is upside down, and the cameras almost touch).
One advantage of the Canons S110 is that the lens ring can be set to control focal length with preset "clicks" at 24, 28, 35, 50, 85, 100 and 120 mm. That makes it much easier than using the zoom buttons on the G12. I set the Aperture at f8 in Manual mode for maximum depth of field, and only adjust the exposure.
In movie mode, I can choose the focal length, and I can correct the exposure of the image(which always seems to be washed out) and lock it. I cannot unfortunately choose aperture and speed manually.
I had to fiddle with the convergence to avoid window violation and to keep the left and right images lined up, so they don't have to be moved sideways later causing cropping on both sides.
After running the video though Premiere to sharpen, increase contrast and color saturation, the results are actually pretty good, as shown in this side by side 3D short clip shot at a focal length of 35mm. I like the way the arm extends out in front of the window as the camera gets closer to the subjects, but it is almost too much, depending on how far one is from the screen. That is one of the problems of 3D: the further away one is from the screen, the more depth the image has.
I repeated the same test with a 50mm focal length.
One other problem visible at the beginning of this video is that the further back in the window the subject is, the further apart the two images are, and that requires the eyes to diverge quite a bit. That is more difficult that having them converge, which is the case when objects are in front of the window. Objects on the window plane have almost no separation.
Therefore, it seems best to keep the main subject fairly close behind the window. Objects that entirely fit in the window can be floating in front of it, as well as protrusions(like an extended arm, a stick, etc...).
It is also better to dolly out from a close up to a mid shot, with the convergence set for the close up(the main subject images almost line up). That way, it is easier for the eyes to diverge following the images as they separate and the subject recedes deeper into the window.
Here is another test video dolly shot with the focal length set at a longer 85mm. The camera then goes from 22" to 48" from the subject. The lenses being 3" apart, we are still very far from the 1/30 rule, and the perspective is exaggerated, but it somehow works.
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