i think that that has to do with the fact that the camera uses a viewing frustrum and not an arc equivelent because if you think about this
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the distance between object1 is greater than that of object 2 yet it still lies within the view and therefore is not clipped, thats my theory at least
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the distance between object1 is greater than that of object 2 yet it still lies within the view and therefore is not clipped, thats my theory at least