Transfering photos from MBP to Mac Mini
The default location for the Aperture Library is Macintosh HD/Home User/Pictures/Aperture Library.
You can move the entire library to the Mac Mini.
If you have a Firewire cable the easiest way to do it is to use Target Disk Mode. It turns your old computer into an external HD.
The Mac Mini has a Firewire 800 port and depending on how old your MBP is it may have a Firewire 400 or 800 port. If it's 400 you will need a cable that is Firewire 400 on one end and 800 on the other.
You could also turn on File Sharing in the System Preferences and connect the two with an ethernet cable. I'd suggest turning off WiFi to make sure the network connection is via the ethernet and not WiFi. If your library is large any type of WiFi transfer will take a LOOONG time.
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