Hey - I am a hack photo guy mostly shooting my kids sports in RAW. Have 256GB HHD in my 2012 MBP so I want to move the Library onto a USB3 1TB external When I install Aperture and set it to Reference Masters on the external drive, I would like to have jpeg (previews) on the laptop HDD. Wondering if the jpeg files would be accessible when the external is not connected? Also wondering what the work flow would be while travelling. Can I dump the RAWs onto the internal HDD while away and move them to the external when I get home OR should I just travel with the external? Thanks in advance. Love this forum!