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Lecture 15: Cameras & Lenses (23)

In lecture, Professor Ng mentioned that for an object to be this large in the picture when using a small focal length, the object has to be very close to the camera, and I'm wondering if this is the same effect as the "Objects in mirror may be closer than they appear" effect in sideview car mirrors since I think they're constructed to have a larger field of view as well.


I think this is also the case. How does phones with multiple cameras compensate for the difference in focal length from each of the cameras?


@jonathanlu31 When Professor mentioned this, I thought about the same thing and related it to the side mirrors in cars. After reading a bit, I found that the "Objects in mirror may be closer than they appear" effect is also due to the wide-angle lens and small focal length, ultimately producing a larger field of view and a greater amount of distortion relative to when a narrow-angle lens or a larger focal length are used. To provide a better view of the surrounding environment, car manufacturers opt for a wide angle fov but the tradeoff is that closer objects are distorted and seem larger.


I think in the last sentence, @waleedlatif1 meant objects seem smaller and thus have the appearance of being further away (than they are in a normal mirror). For anyone curious, this is because the mirror is convex. See a visualization and explanation here:

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