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I was reading about crop factors that for example a Polaroid land camera on f/3.2 lens is something around f/1.4 equivalent in 35mm film including the crop factor. ( Until now I was under impression that crop factor only affect the focal point ).

So does that mean when I am measuring with a light meter, should I convert the f number too depending on the crop factor and use that new value for the light meter readings?

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No, the light meter reading (for example, ISO 100, f/11, 1/200 second) already applies to any camera, any sensor size, any crop factor. That''s the beauty of the "f/stop" numbering system.

Crop factor might apply to focal length and sensor size situations, but Not to exposure.

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No correction is needed. The image formed by the lens is still that of a lens of the nominal focal length. You can use a lens designed for a full frame body on a cropped-frame body, but the image formed by the lens won't change because you put a body with a smaller sensor behind it.
What changes is the part of the image that is used: a sensor smaller than 24×36 mm only uses the center of the image, and thus has a field of view that is smaller than for a full-frame (24×36 mm) sensor. The crop factor expresses this, and only this.

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