01-18-2015, 02:28 PM
If you have an empty 5G dmg you can put 4G+ in and the size will remain 5G. Putting in 5G will be a tight squeeze. When the dmg is created it has a fixed size just like a regular disk. But if it is created as a sparse image, a maximum size can be set and you can fill it up to that amount. If the original (sparse)dmg is set for a 100G maximum you are okay but if the original was set for 5G max, then you need to create a new one (either a dmg or a sparse image). I don't recall what the default size for a new sparse dmg is (26 MB?). It grows automatically to accommodate whatever you put in up to the maximum. To paraphrase a Missing Manual segment: a dmg is like a steel bucket and a sparse image is like an accordion file.