Cleaning the garbage out of Aperture

I also mark many images that I will never look at, such as 19 out of the 20 images I took of a lion sleeping or of a bird in flight. Does it make any sense to actually delete them and the rebuild the Aperture library so it only contains stuff that might be viewed?

Go ahead and delete any images that are redundant or technically imperfect - if you can make up your mind on which images you can part with. That is what I am doing regularly; otherwise the disk on my MBP would fill up too quickly.

Deleteing the last version of an image will also delete the previews and thumbnails, and the master iamge file, if it is included in the Aperture library. So there will be no need to rebuild the library, unless the library is corrupted in some way.

Deleting something permanently, whether out of Aperture or off the HD is really a personal call. No one here can tell you if it makes 'sense'.

You'll certainly gain (some) disk space how much in relationship to the total library size will vary greatly depending on the file type, if previews are generated for the image and how big the preview is. Deleting obviously 'bad' images (lens cap on, flash failed to fire, etc) makes some 'sense'. Its unlikely these images will ever be any good for anything.

Where it becomes more of a gray area are the rest, images were you don't like the composition or lighting or whatever. There have been any number of time when I've gone into my box of rejected slides (yes I'm of the never throw out anything school) and looked at something that was obviously bad when I first looked at it but now I see something I missed the first time.

Take your case of those 20 Lion images. If you can really say with absolute certainty that 19 of those images don;t deserve to live then delete away but if you're not 100% certain remember disk is cheap.

There are a number of steps you could take to reduce library size, you could delete the previews for these images )previews can eat up a ton of space) you could export all these image as a new library and store it offline.

One thing you won;t have to do if you delete these images; There is no need to rebuild the library to reclaim the space they took up.

regards

The best course of action if you decide to do this would be to gather up all your rejected images the ones you want to do this for and put them in there own section of the library, either all in one project you make for this or else a folder structure that contains the projects were you put these images. Then select the images and go to Photos->Delete Previews. (or else right click and select it from the contextual menu)

To keep the previews from being regenerated for the images in these projects you will need to select the project(s) and then click the gear icon at the top of the Library tab and unselect Maintain Previews for Project

That will prevent previews from being generated for the images in these project(s)