Duplication of photos on HD using iPhoto...

Question

When I download photos from my digital camera, they go to a folder on the HD for that camera.  When I load these photos manually into iPhoto does that also take additional HD space by having them in iPhoto Library?

Answer 1

By default, yes it does. You can change this, but I don't recommend you do. Why not import directly to iPhoto?
How to do it:
Simply go to iPhoto Menu -> Preferences -> Advanced and uncheck 'Copy Files to the iPhoto Library on Import'.
What Happens:
Now iPhoto will not copy the files, but rather simply reference them on your HD. To do this it will create an alias in the Originals Folder that points to your file. It will still create a thumbnail and, if you modify the pics, a Modified version within the iPhoto Library Folder.
Some things to consider:
1. Importing and deleting pics are more complex procedures. You have to to put the files where they will be stored before importing them. When you delete them you'll need to remove the files from the HD yourself.
2. You cannot move or rename the files on your system or iPhoto will lose track of them on systems prior to 10.5 and iPhoto 08. Even with the later versions issues can still arise if you move the referenced files to new volumes or between volumes.
3. Most importantly, migrating to a new disk or computer can be much more complex.
4. Because iPhoto has no tools for managing Referenced Files, if, for some reason, the path to the photos changes then you could find yourself resolving aliases for each photo in the Library one by one.
My own opinion:
I've yet to see a good reason to run iPhoto in referenced mode unless you're using two photo organisers
If disk space is an issue, you can run an entire iPhoto Library from an external disk formatted Mac OS Extended (Journaled) 
1. Quit iPhoto
2. Copy the iPhoto Library as an entity from your Pictures Folder to the External Disk.
3. Hold down the option (or alt) key while launching iPhoto. From the resulting menu select 'Choose Library' and navigate to the new location. From that point on this will be the default location of your library.
4. Test the library and when you're sure all is well, trash the one on your internal HD to free up space.
If you're concerned about accessing the files,
There are many, many ways to access your files in iPhoto:   You can use any Open / Attach / Browse dialogue. On the left there's a Media heading, your pics can be accessed there. Command-Click for selecting multiple pics.
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(Note the above illustration is not a Finder Window. It's the dialogue you get when you go File -> Open)
You can access the Library from the New Message Window in Mail:
Uploaded with plasq's Skitch!
There's a similar option in Outlook and many, many other apps.  If you use Apple's Mail, Entourage, AOL or Eudora you can email from within iPhoto.
If you use a Cocoa-based Browser such as Safari, you can drag the pics from the iPhoto Window to the Attach window in the browser.
If you want to access the files with iPhoto not running:
For users of 10.6 and later:  You can download a free Services component from MacOSXAutomation  which will give you access to the iPhoto Library from your Services Menu.
Using the Services Preference Pane you can even create a keyboard shortcut for it.
For Users of 10.4 and 10.5 Create a Media Browser using Automator (takes about 10 seconds) or use this free utility Karelia iMedia Browser
Other options include:
Drag and Drop: Drag a photo from the iPhoto Window to the desktop, there iPhoto will make a full-sized copy of the pic.
File -> Export: Select the files in the iPhoto Window and go File -> Export. The dialogue will give you various options, including altering the format, naming the files and changing the size. Again, producing a copy.
Show File:  a. On iPhoto 09 and earlier:  Right- (or Control-) Click on a pic and in the resulting dialogue choose 'Show File'. A Finder window will pop open with the file already selected.    3.b.
b: On iPhoto 11 and later: Select one of the affected photos in the iPhoto Window and go File -> Reveal in Finder -> Original. A Finder window will pop open with the file already selected.
Want to use another Editor for your Photos?
You can set Photoshop (or any image editor) as an external editor in iPhoto. (Preferences -> General -> Edit Photo: Choose from the Drop Down Menu.) This way, when you double click a pic to edit in iPhoto it will open automatically in Photoshop or your Image Editor, and when you save it it's sent back to iPhoto automatically. This is the only way that edits made in another application will be displayed in iPhoto.
Regards
TD