Crop a Close-Up Photograph in Postproduction
Perhaps you're testing your lenses for close-up capabilities, and the closest you were able to get to your subject still left something to be desired, and you feel there’s too much unused space in your frame.
You can crop into the image on your computer and test the results for that. The figure shows an example of an image being cropped for this purpose. The grey area represents what will be eliminated and the black outline represents the new image frame.
After you’ve cropped the image (using the crop tool in your photo-editing program) keep in mind that you decreased the overall image size. The new image file will produce a smaller print size than the original. In some cases you may need to increase the image size in order to get the print size you want.
If you do increase the image size, be sure to view it again at 100 percent to make sure you didn’t lose a substantial (or noticeable) level of quality in sharpness.
135mm, 1/800, f/5.6, 100
Drastically increasing the size of an image can cause blurring and pixelation (individual pixels are increased in size and become visible to the naked eye). If the original pixel is enlarged greatly, it actually becomes a clearly visible element of the image.
A camera with a full-frame digital sensor provides more image detail to work with when cropping. In many cases, you can crop out 50 percent of the image frame without losing too much fine detail in your prints.
A cropped sensor camera, on the other hand, has already cropped into the original image created by your lens. If you make a dramatic crop to an image created with this type of camera, you’re more likely to notice a major loss of quality in your prints.