Q: "Do not import duplicates" IS importing duplicates

This duplicate recognition is bothering me too.  Therefore I've been doing some testing.  Renaming of the files will kill Aperture's ability to recognize duplicates.  Identical images with different names are not regarded as duplicates.

What was worrying me, was that if my library already contained an image called XYZ01234.JPG and I tried to import another, different, image of the same name, that the second impart would bypass that image if I had set "Do Not Import Duplicates".

Strangely, this doesn't happen it seems.  I have successfully imported two different images which share the same name, so that is a relief.

When all else fails, I sometimes remember to go back and read the manual.  RTFM.

This is one of those rare cases where I tried RTFM.  Here is what it says:-

"When you import images, Aperture automatically checks to see if any of the images are duplicates of previously imported images. Aperture checks the filename of the master to determine if an image is a duplicate of one in the library. Select the “Do not import duplicates” checkbox to prevent Aperture from importing duplicates."

This is by no means an unambiguous definition of its behavior, but it clearly says that file name is part of the process.  Clearly I should have read this some time ago, but better late than never.

My conclusion is that Aperture doesn't work the way I'd like it to, but there must be a possible workaround.

This is not thought through really well yet, but maybe the answer is to eliminate duplicates before importing the images.

At this stage, I can only see one scenario that might work.

1. Use referenced masters in the library
2. Import masters from the camera to a folder outside the Aperture Library and without reference to that library
3. Use deduplication software on a combination of the referenced masters and the newly arrived folder of masters, eliminating any new masters that match any of the old masters.
4. Import the remaining new masters

Clunky, I know.  But what do you people think?  Could this be a way to go?

Your opinions will be valued

Maybe or maybe not significant...

When you import RAWs matching already imported JPEGs, you must not change the JPEGs' timestamps, otherwise even identical filenames fail to match. One might infer that when Aperture is sorting out duplicate filenames it also looks at the timestamp.

Good point!  The timestamp is probably what is differentiating different images with the same file name, possibly in combination with other metadata.

I'm interested in opinions from Aperture users who regularly rename images on import, since that breaks Aperture's duplicate detection.

The following are not duplicates:

renamed.jpg

img_001.jpg

The following are duplicates:

img_001.jpg

img_001.jpg

I would not expect duplicate detection to 'work' on masters that have been renamed since they are not duplicates of the files being imported.

On the other hand, people whose workflow involves automatic renaming of masters as part of the Aperture Import process would probably expect that Aperture's duplicate detection would work.  For such users, the camera-generated file name has no meaning or value.

True, some users may expect that. However, the definition of 'duplicate' does not change based on a users workflow. If "Do not import duplicates" is enabled, I expect it to do just that.

I've just come across this issue, and have found that changing my timezone back to the time zone that I used for importing the files originally makes the "Do not import duplicates" function work as expected.