Aperture manages my main catalog of images, but I like to use iPhoto 6 too. iPhoto is much easier on my older computers — plus it has some great output options, and I like its casual workflow.
You can tap your Aperture library from within iPhoto. First, make sure you have the current versions of both applications. Then launch Aperture. Finally, launch iPhoto. In the File popup menu in iPhoto, you’ll see Show Aperture Library…
Note: You’ll only be able to use Aperture images that have previews. Also, make sure you have “sharing your previews with iLife applications” turned on in the Aperture Preferences window.
You can browse your images from your Aperture library in iPhoto until you find what you’re looking for. The browse window is adjustable, so feel free to resize as needed.
Now, all you have to do is drag the image you want from the Aperture Photos window into your iPhoto Library.
Great way to keep a master catalog and have fun with your pictures too.