The Image Verification Phase

Once you've copied the raw files to your hard disk, the next thing to do is to point Bridge at the folder containing the raw images. Bridge is command central for dealing with hundreds of images. You'll use it to make your initial selects, to apply and edit metadata including Camera Raw settings, and to control the processing of the raw images into a deliverable form.

But before you start doing any of these things, it's a good idea to give Bridge a few minutes to generate the thumbnails and previews and to read the image metadata. The old File Browser was pretty much unusable while it was building previews. As a standalone multithreaded application Bridge is much more responsive while it's building previews, but whenever possible, it's still a good idea to let it finish building the cache for the folder before you start working.

The reason is simple. While you can identify raw images as soon as the thumbnail appears, and open them in Camera Raw, the thumbnails are generated by the camera, and Bridge simply reads them. To build the high-quality previews, though, Camera Raw actually reads the raw data.

Verifying Images

If Camera Raw has any problem reading the images, the problems will only show up on the high-quality thumbnail and preview. The initial thumbnails are the camera-generated ones, and they don't indicate that the raw file has been read successfully. The high-quality ones do indicate that the raw file has been read successfully, so wait until you see them before you erase the raw image files from the camera media.

If there's a problem with the raw data, you won't see a high-quality preview, so the preview-building process verifies that the raw data has been copied correctly. It's the first time you actually see a processed version of the raw image created from the raw file on the computer.

If you see a problem at this stage, check the second copy (if you made one) or go back to the camera mediayou haven't reformatted it yet, right? It's fairly rare for the data to get corrupted in the camera (though it does sometimes happen, particularly in burst-mode shooting), so the first suspect should be the card reader.

If you have only one reader available, try copying the problem images one by one. If you have a second reader available, try copying the files using the second reader. If this copy fails, try running the rescue software provided by the card vendor. If none of these suggestions work, your options are to reshoot, to accept the loss and move on, or to resort to an expensive data-recovery service.

Feeding the Cache

Bridge's cache holds the thumbnails, previews, and sort order information for each folder at which you point it. (In the case of other file types, the cache may contain additional information, but with raw files, the thumbnails, previews, and sort order are the only pieces of data that are uniquely stored in the Bridge cache.) With a brand-new folder of images, there's no custom sort order, so the caching process consists of reading the thumbnails and EXIF metadata, and building the high-quality previews.

This is a two-pass process. The first pass reads the thumbnails and metadata, the second pass actually uses Camera Raw to build the high-quality previewsit's this second pass that lets you verify the raw images. When you point Bridge at a folder of raw images for the first time, it goes to work. The first thing you'll see is a message that reads "Examining folder contents"see Figure 7-3.

Figure 7-3. Examining folder contents

With the typical hundred images per folder that cameras write, the "Examining folder contents" message flashes by so quickly that if you blink, you may miss it. The second message that appears is "Getting filename thumbnail." This second pass takes a little longer, because it's extracting the camera-created thumbnail and metadata from the raw imagessee Figure 7-4.

Figure 7-4. Getting thumbnails

The last phase of the initial cache-building process is also the most crucial onegenerating previews. In this phase, Bridge uses Camera Raw to build higher-quality thumbnails than the ones that appear initially. (They're downsampled versions of the result you'd get if you processed the raw file using the current Camera Default settings for the camera that shot the images in Camera Raw.) If you look closely, you can see the thumbnails updating. (Even in print at this small size, you can see the difference between the thumbnails in Figure 7-4 and the ones in Figure 7-5.) The status message reads "Generating filename preview"see Figure 7-5.

Figure 7-5. Generating previews

Once Bridge has completed the process of generating the previews, it displays a message that states the number of images in the folder, indicating that it's ready for you to proceed to the preproduction phase. Large previews appear instantly when you advance from one image to another, so you can work quickly.

Interrupting the Cache

In an ideal scenario, you'll follow the procedures described in the previous section, but in the real world, scenarios are often less than ideal. In this section, I'll cover a couple of ways to start work while Bridge is still building its cache. You're still verifiying the images, just not necessarily in the order in which Bridge loaded them.

If you need to see and start working with a specific image right now, you can force Bridge to read all the data and build the preview by selecting the thumbnail in the Bridge window. Bridge gives preference to that image, and generates a preview before moving on to the other images, even if you do so during the thumbnail pass. However, this approach doesn't work with multiple imagesBridge builds the preview for the first selected image, then carries on reading thumbnails. You can also scroll the Bridge window to give preference to a series of imagesBridge always builds previews for those images whose thumbnails are currently visible in the main window first.

But the most effective way of getting images while Bridge is still caching is to select the thumbnails, then press Command-O to open the images in Camera Raw filmstrip mode hosted by Photoshop. Camera Raw builds the previews very quickly, and because it's hosted by Photoshop, it doesn't have any effect on Bridge's caching performance. You can apply ratings or labels in Camera Raw in addition to editing the images. The only thing you can't do is to apply keywords, or metadata other than labels, ratings, and Camera Raw settings.

Tip

Download to Your Fastest Drive. The cache-building process is largely dependent on disk speed, so the faster the drive to which you download the raw images, the faster Bridge builds the cache. Consider dedicating a partition on your fastest drive, the same size as your camera media, for downloading and caching your raw images. If you use distributed caches in Bridge, you can then copy the folder to another drive without having to do anything else to keep your thumbnails and previews intact.

Caching Multiple Folders

Most cameras create subfolders on the camera media with 100 images in each. If you use larger-capacity cards, you may have three or four image folders. The fastest way to deal with multiple folders is to copy all the image folders to a single enclosing folder. Then, when the copy is complete, point Bridge at the enclosing folder and choose Build Cache for Subfolders from Bridge's Tools>Cache menu. Bridge builds a cache for each subfolder in the enclosing folder, reading the thumbnails and metadata and generating previews for all the images contained in the subfolders. It displays a status message so you'll know when it's done.