D7100 1.3x crop in sensor vs Crop in Software?

Not really

In "crop mode" you are not using the full frame. The image that hits the sensor is the same in both cases. In PP you're cutting away the outer part of the image and only using that part of the image that hit the 80% center of the sensor. In "crop mode" you're only recording what hit the center of the sensor. In both case..the same photons hit the same part of the sensor and passed through the same center of the lens. In crop mode you get a square in the middle of the viewfinder you have to frame your photo in. Only advantage to "crop mode" is smaller file size faster FPS......I think

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My opinions are my own and not those of DPR or its administration. They carry no 'special' value (except to me and Lacie of course)