When I connect my OnePlus One by USB to Windows 7 or Windows 10 (I also tried Ubuntu), I first drag down the notification panel, and then select "File transfers" (I also tried "Photo Transfer (PTP)").
Under Windows I can then navigate to
Computer\A0001\Internal storage\DCIM\Camera, and access 236 of my most recent photos and videos. However, I have more photos and videos than this on the phone. If I open the default camera application, and swipe left from the right edge, I can see many more photos - all the photos I've taken in fact. Why does Windows not show me these? Are they stored in another location? Ultimately, how can I tranfer them to my computer.