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For example, the D3300 is advertised to have 24.2 megapixels, but its highest camera resolution in all types of settings including raw and full manual, the output resolution becomes 6000×4000 instead of 6016×4000 like the D3200. I was wondering if those 16 pixels are used for some sort of physical noise reduction mechanism or are just simply cropped off for whatever reason.
I've also talked with Nikon support and they don't know why that happens. They implied that the image is simply cropped, but they were unsure why it does this.