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<blockquote data-quote="WayneF" data-source="post: 352273" data-attributes="member: 12496">Crop is a different argument than exposure.&nbsp; &nbsp; See <a href="http://www.scantips.com/lights/cropfactor.html" target="_blank">FX - DX Lens Crop Factor</a>A FX D610 is 24 megapixels.&nbsp; In DX crop mode, it is cropped to about 10 megapixels, so this is a limitation&nbsp; in reproduction.&nbsp;&nbsp; A DX D7100 is also 24 megapixels, but it &quot;packs&quot; them into DX space.&nbsp; It has all 24 megapixels &quot;left&quot;.But if same lens (all else the same), it is obviously exactly the same image in either DX space. The only difference is the digital reproduction of that cropped image.(I am ignoring that 10 megapixels in DX space are obviously larger pixels than 24 megapixels in DX space, which should help noise in low light situations, if 10 megapixels are enough for our use.&nbsp; If FX is not cropped, even better.)Speaking of image quality, the pixels do not create the image.&nbsp; The lens creates the image, projected onto the sensor.&nbsp; If the same lens , all else the same (subject, focus distance, aperture, etc), then of course the same lens projects the same image onto either sensor area.&nbsp; DX just crops to use a smaller part of it, which then necessarily has to be enlarged more to compare at same size as FX. ( We perceive this DX crop and then enlargement as appearing as a telephoto effect, but we can see exactly the same effect simply by cropping any old image, and then enlarging it back.)The megapixels merely try to reproduce that existing lens image digitally.&nbsp; A digital copy.&nbsp; Like scanners, more pixels can improve the reproduction, but reproduction can never improve the lens image quality in any way.&nbsp; At best, we hopefully get nearly what we started with.</blockquote>

[QUOTE="WayneF, post: 352273, member: 12496"] Crop is a different argument than exposure. See [URL="http://www.scantips.com/lights/cropfactor.html"]FX - DX Lens Crop Factor[/URL] A FX D610 is 24 megapixels. In DX crop mode, it is cropped to about 10 megapixels, so this is a limitation in reproduction. A DX D7100 is also 24 megapixels, but it "packs" them into DX space. It has all 24 megapixels "left". But if same lens (all else the same), it is obviously exactly the same image in either DX space. The only difference is the digital reproduction of that cropped image. (I am ignoring that 10 megapixels in DX space are obviously larger pixels than 24 megapixels in DX space, which should help noise in low light situations, if 10 megapixels are enough for our use. If FX is not cropped, even better.) Speaking of image quality, [B]the pixels do not create the image[/B]. The lens creates the image, projected onto the sensor. If the same lens , all else the same (subject, focus distance, aperture, etc), then of course the same lens projects the same image onto either sensor area. DX just crops to use a smaller part of it, which then necessarily has to be enlarged more to compare at same size as FX. ( We perceive this DX crop and then enlargement as appearing as a telephoto effect, but we can see exactly the same effect simply by cropping any old image, and then enlarging it back.) [B]The megapixels merely try to reproduce that existing lens image digitally[/B]. A digital copy. Like scanners, more pixels can improve the reproduction, but reproduction can never improve the lens image quality in any way. At best, we hopefully get nearly what we started with. [/QUOTE]

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