Question

whst is focal plane?​

Answer 1

Answer:

The focal plane is the distance between your camera lens and the perfect point of focus in an image. This area is located a certain distance in front of your camera lens, and spans horizontally, left to right across your frame.

Answer 2

Answer:

The plane through the focus perpendicular to the axis of a mirror or lens.

In camera design, a focal-plane shutter is a type of photographic shutter that is positioned immediately in front of the focal plane of the camera, that is, right in front of the photographic film or image sensor.

Explanation:

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