Digital Photographer's Software Guide - Bertemes - Net

Aperture’s Architecture and Concepts
Chapter 38 ■ Two Featured Products 441
Here is a brief overview of some of the concepts and their implementation in Aperture.
Masters
Master files are equivalent to negatives in the sense that they remain stored away,
untouched, until needed. If they are “fully managed,” they dwell in a Library, the
whole of which can be backed up in a vault on an external device. If they are “referenced,”
they dwell elsewhere, possibly on another computer, on a network, or even
on-the-shelf in DVD format. Masters are very likely to be RAW files, but they can also
be GIF, JPEG, TIFF, DNG, or PNG files.
When you edit an image, you do not edit the master, but a version of it—and you can
create as many versions as you like. If you delete a master, you also remove all the
versions of it from the Library, including adjustments and metadata. There is no
“undo” facility with this delete, but if you have backed up the Library of managed
images in a vault, a copy of the master will still exist in a folder marked Deleted
Images. Aperture lets you work with hundreds of thousands of master files.
Projects, Albums, and Folders
Aperture’s three “containers,” or ways of grouping images, are called Projects, Albums,
and Folders. The first of these, Projects, contains the master files. They are like sleeves
that hold negatives, only much bigger as they can hold tens of thousands of master
files. A master can dwell in only one Project at a time but can appear as a referenced
image in many different Albums: collections of photos, very much like physical albums.
The third container, Folders, is the most tricky from a conceptual point of view.
You can put just about everything in a Folder, including Projects, Albums, and other
elements like Aperture-generated books and Web pages. You can drag a Folder around
the file structure and drop items into it. Folders are powerful organizational tools,
but, when using them, watch out for the way they swallow the other containers.
Previews
A preview is a JPEG image created by Aperture to represent the original master,
together with any adjustments applied to it. Aperture may sometimes display the
preview as a thumbnail in the browser window, but when necessary can make it
much larger. You have full control over the quality of previews and can even dispense
with them altogether, although that is not recommended. Apple originally intended
to generate them on-the-fly but decided to store them instead, partly so that other
programs—such as iLife and iWork—could access them, and partly so that referenced
images would be properly represented even when offline. Moving from displaying the
preview to showing the Master image is usually swift, depending on the size of the
latter. A new Quick Preview mode loads only the previews in order to accelerate
browsing speed.