JChenault
Well-Known Member
Oh, so the second focal point is after the gate, which is why the gobo must be inserted upside down?
Er No
The gobo must be inserted backwards because when you project an image through a lens it reverses the image (depending where the image plane is in relation to the focal point) The image in your camera is reversed. When you look through a telescope the image is reversed when you put a slide in a slide projector ( remember slide projectors ) the image is reversed.
Take (say) a 6x9 lens. Hold it 9 inches from the floor, see that it is projecting an image of the lights on the ceiling, note that the image is reversed.
If you remove the reflector from an ERS, and put in a gobo and focus the light ( we don't need no stinking foci points ) it will be dim, but reversed.
If you look at a focused ERS in a smokey environment, you notice the beam narrows then expands. ( usually within a foot or two of the unit) If you focus the image on a screen before you get to the narrowing of the beam, it is not reversed ( but very small) After the focus point, it is reversed