Due to popular demand I will provide some additional detail to my previous Adobe Lightroom 2 versus Apple Aperture 2 article. Both of these applications are so rich in both functionality and the multitude of ways they can used to support a photographic work-flow it will take a serious of articles to even scratch the surface. So, no better place to start than the image file management capabilities. Most photographers adopting either one of these applications will not delve into this subject until way down the road and when they do they usually have about 1,000 questions that they NEED answers to right now.
Aperture gives you two different ways to manage your original "master" image files. The first way is the managed masters method. Using managed masters Aperture pretty much completely insulates you from having to manage your images files at all. Aperture imports the images into its Library and figures out where to put them for you. This is great for libraries that are not of a massive scale, like on your laptop. Using managed masters pretty much frees you from having to make decisions about where to put the images that you download from your camera. One thing that I need to clear up about managed masters and the Aperture library is the unreasonable fear that a lot of photographers have about Aperture somehow squirlling their images away in some super secret, unintelligible, highly complicated, weirdo structure that is just waiting for the slightest breeze to blow for them to be lost and gone forever. Let me put you at ease right now, this is not the case. The Aperture library is pretty much a folder/directory with a special flag that makes it look like one big file when viewed in the Finder. Don't believe me? Fire up a terminal (command line) window and cd to ~/Pictures and then do an ls on the "Aperture Library.aplibraryls". Look Ma, I can see all the stuff in there. Yup, and guess what. Aperture automagically does the exact same thing you would probably do manually it creates another directory inside for each project and puts your original master images in there. I think it is hilarious how many people I see mirror the exact same structure on a single disk manually instead of letting Aperture do it for them for irrational fear of….Nothing?
This brings us to the second way that Aperture gives you to manage your original master images. That way is using "referenced masters". Using referenced masters allows you to put the original master images anywhere you like. The only really good reason to use referenced masters with Aperture is to allow you to use more than one drive to store your images. This is really simple, the interesting part is you don't have to decide one way or the other. With Aperture you can mix and match both when you import and down the road. For example let's say you only have one machine and it's a laptop with one internal drive. You could easily have all of you active projects use managed masters and then use Aperture to relocate them as referenced masters onto an external HD that you leave behind. If you need them active again just use Aperture to consolidate them back into the library if you want. The big thing with Aperture and major difference to Lightroom is that Aperture pretty much abstracts file management from the rest of your work-flow. When you look at your projects and their organizational structure inside of Aperture you have no indication of where your files are, nor do you care. If you want to manage the location of your files there are a couple of functions that allow you to do this but it has nothing to do with the way that you organize your projects or images within Aperture. The important functions are Relocate Masters, Consolidate Masters, and Manage Referenced. Relocate moves your original master images file to wherever you specify, including from managed to referenced. Consolidate takes whatever masters you have selected and moves them from being referenced to being managed back inside the Aperture library, neatly into a corresponding folder to the project that they live in. Last but not least Manage allows you to do a ton of really powerful things like re-hook the images versions to referenced masters when you move them on purpose or by accident somewhere different. I am talking way different because if you just rename the folder they reside in Aperture deals with that automagically.
I have dropped a couple of hints so far about this but here is the deal, there does not have to be any relationship at all between what Aperture project an image lives in and where the corresponding original master image resides on disk. In fact if you wanted to some of the images can be managed masters, some can be referenced from a different HD, and some can be referenced from a DVD if you want. Not only that but you can select what ever images in any combination you want, a whole project, a couple of images in a project, the whole library, etc, and then use the file management functions that I described on that set. You don't have to do this, you can get involved as much or as little as you would like to in where your images are stored and it has no bearing with how your projects within Aperture are organized.
The reason that I spent so much time on how Aperture does things is because it makes explaining how Lightroom does things really easy. In Lightroom your folder/directory structure is your project structure, end of story. The on disk location of your originals images and how they are divided between folders is the way they are organized in Lightroom. What disk and what folder they are in is in your face and not at all abstracted from you at all. The only thing that you can do is move the folder around as a whole with all of the images in it, even to another HD and then tell Lightroom what you did. The other thing that you can do is move images out of one folder to some other folder and then tell Lightroom where to find them but that changes the way that your project structure in Lightroom is organized. Bottom Line - Aperture original master image location and project structure are completely independent. In Lightroom original master image location is tied directly to project structure and organization. The way that Lightroom works is a very special case of the way Aperture can work.
A coupe of other minor things to note that can be considered file management. Both Lightroom and Aperture generate JPG preview images of RAW files that are imported. The previews allow you to view your images and perform metadata, organization related tasks, slide shows, etc. even when the RAW master files are "off-line". Previews also help speed some things up in both applications when there is no need to render the RAW file over and over. Aperture gives you a finer degree of control over the size of the previews generated and when they are generated. You can generate them automatically or completely manually with Aperture. You can delete any subset of image previews that you would like. This comes in handy when using a replicated library approach to dealing with a portable version of your library. For the esoterically oriented Lightroom and Aperture handle things a bit differently when and if you shoot RAW+JPG. When you import RAW+JPG into Aperture it looks like you have only one image, the RAW file. Behind the scenes Aperture is managing both of these files as a sort of compound master images. By default you will be looking at and working on a version of the RAW file. To see the JPG version you will have to right click and choose "new version from master JPG". In Lightroom the default is to alegidly use the JPG as some sort of preview but I have not seen any indication that this is happening and personally wouldn't because that would probably be really confusing. Once they are imported into Lightroom it will never show you the JPG again but the image is politely labeled RAW+JPG. The other option in Lightroom is to set a global option to import them as two separate images in a stack.
Whew that was a long one but I thought it deserved to be tackled given how much confusion and misinformation is out there on the subject. My vote in terms of overall file management capability has to go to Aperture for overall flexibility and Lightroom for simplicity. Some photographers just like the comfort level of doing things the same way they always have in terms of organizing their files and like that the location of them is brutally apparent. I like the abstraction of image file location until I really want to be involved with it.
As always let me know if you have any questions or comments.