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Message: <blockquote data-quote="tdodd" data-source="post: 1565269" data-attributes="member: 55450">Look at the % figure as a viewing magnification, not as a proportion of the original that you cropped out.To follow on from what Roy said, this forum allow .JPG attachments of up to 1024x800 pixels. Your 50D produces files of 4753x3168 pixels. If you wanted to display the whole image from your 50D you would have to resize it to fit into a 1024x800 maximum size. You'd have to resize it by a factor of 4752:1024 or about 4.6:1 or about 22%. So without cropping anything you'd be viewing at 22% magnification.Now, lets say you crop your original a bit. To make the maths simple let's suppose you crop it to 4096x3200. To fit that into your 1024x800 "window" you'd need to view it at exactly 25% magnification. You now have a 25% crop.If you cropped even tighter, to 2048x1600 you would have to view it at half size - 50% magnification in order to fit your image into the available space. You would have a 50% crop.Finally, if you were to crop out just 1024x800 pixels from your original, you could display those pixels in that 1024x600 window with no resizing at all. You would be viewing pixels display at 1:1 ratio, or 100%.You could crop smaller, if you wanted, to 800x533, for example, and that would fit into the 1024x800 "window" with room to spare. That would also be a 100% crop.So the 100% refers to the viewing magnification, not the amount of image you cropped out. 100% crops are useful because they show you each and every pixel that the camera captured, and there are no odd artefcats of scaling/resizing, the success of which depends on the capabilities of the resizing software you use.In DPP, in order to produce a 100% crop, all you need to do is crop a section of your image to 1024x800 or smaller and then output that cropped file without resizing.</blockquote>

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