I am having trouble cropping some pictures in LR. Some pictures I have uploaded crop fine, others get smaller after I crop them. For instance, if I am cropping a picture, the cropped part should enlarge and fill the screen. Instead, the cropped part stays the size it is in the original picture.
Look at the actual size of the image in MP and number of pixels vertically and horizontally. This happens when an image is so small to begin with that cropping part of it out makes it even smaller. LR will not expand an image beyond its actual size, resolution.