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Situation A: 25mm lense, subject at 5 meters. Take a shot with the Subject covering half of the sensor.
Situation B: 50mm lense, subject at 5 meters, Take a shot with the Subject covering the Whole sensor, load in Photoshop, resize subject to the same size as if it was taken with the 25mm lense.
Forgetting about image quality, lense quality, aperture, edge distortion, image-degradation from resizing and taking into account only the proportion and perspective of the subject if the distance to the subject does not change, will I notice a difference in the two images, or will the result be identical?
I want to make composites, and I know that the subject is supposed to be placed 5 meters from the photographer on scene. If the vaniscing point is identical, then the only thing i have to take into account is that the subject should be at the very same distance when it is photographed in the studio.. If this is right, then it makes no difference what focal lenght I use, as long as the distance to the subject is the same... (obviously illumination and aperture and all the rest have to match..)