I’ll likely be shot at dawn since I’m sure this has been asked and answered a zillion times before but I’m done with searching for the specifics.
I started using Aperture way back with “3” and have kept it up to date. But when I first got this Mac i used iPhoto and had a few thousand pix in it. When I acquired Aperture, I migrated my entire iPhoto library to it. All of the photos are available to me in the Aperture Library, BUT I cannot edit them in Aperture. I get a pop up that says the photo is “offline”. I’ve opened iPhoto to see if that helps, but NO. I’ve tried to “locate the referenced file” and that works but does zip to let me edit the old iPhoto. Somehow, can’t recall, I figured a work-around once, I think by dragging the iPhoto pix to the desktop and then importing/dragging it into Aperture? But that is hardly ideal. The photos are a mixture of jpegs and RAW files and there must be an easier way to handle this. Now Photos is coming along and I’m really dreading importing 8-9000 pix into that and then not being able to edit. But, the question of the moment in how do I enable editing of photos in iPhoto in Aperture? Confused? I am.
Similar problem for me. I opened iPhoto and exported all its photos to the desktop. Then I imported these into Aperture from within Aperture. When I did the iPhoto export I think I checked the options to export originals and versions. Once back in Aperture it took some time to reorganize the photos as all the projects and events had gone. To simplify the organization, I used Apertures find by date function to automatically group the new iPhoto imports into years. You could use the same search function to create new albums or folders with whatever date ranges you like. This was time consuming but now all my photos are in Aperture.
Clement