Client Guide : Before You Begin : Working with Color Correction and Profiles

Working with Color Correction and Profiles
Setting up a Color Correction
Xinet includes an ICC-compliant color management engine, Color Vérité, with the Xinet for sites concerned about automating color correction with their workflow. Color Vérité provides the essential piece of an ICC color-managed workflow: the color management module. Because its color transformations occur upon output, without ever changing pixels in the original image file themselves, Color Vérité allows images to remain device-independent. And, because Color Vérité resides on the server, it calculates color transformations rapidly.
Use of Color Vérité within a Xinet workflow is completely optional and can be set on a queue-by queue basis. Talk to your system administrator about setting up Color Vérité enabled queues which will make ICC color transformations upon output. Once that’s done, you need to make sure profiles have been embedded in each of your images.
Getting profiles into images
Color Vérité will only transform color when printing a raster image if the image has an ICC input profile associated with it or if the image is in LAB format. Color Vérité does not transform color in vector graphics. There are several ways to associate a profile with an image, the most typical being to embed it. File formats that support ICC profile embedding include: EPS, JPEG (only for RGB and grayscale), TIFF, Photoshop Native (PSD), and PNG.
Using the server to insert a profile in an image during printing
The administrative GUI offers an option to system administrators, Input ICC Profiles, that allows them to establish a default input profile for images going through the queue. You may have the option enabled. Most sites—unless they have a very closed workflow—won’t want to use this option, however, because images will come in which have been scanned by many kinds of scanners.
So, by default, Xinet assumes that no input profile will be automatically assigned. The software also builds in another safeguard, namely, that if an image comes into the workflow and it already has a profile associated with it, Xinet won’t overwrite that profile, even if you’ve established default profiles.
Using applications to insert profiles
Although it is possible to have Xinet server automatically apply a default ICC profile to all images that pass through one of its print queues, most sites will want to embed profiles in each image. That way, images that come from different digital sources can have appropriate profiles associated with them. Each application (and, often each new version of the application) has its own interface for handling profiles. Refer to your application documentation for details.
Monitoring and Changing Printer Queues
Xinet provides two different ways to monitor printer queues. A printer queue section of the Xinet Administration view provides information for those with appropriate permissions to use a Web browser.
Xinet supports a variety of printer queues with those to which you have access being determined by your Xinet administrator. The following table identifies the icons used with that variety of queues and their states:
 
Represents a “failure” queue; i.e., a queue where requests that have errors in them will wait. It is used in combination with hold and print to file or screen queues and is useful when you want to look at PostScript errors.
Represents a print queue that uses the BSD Unix lpr(1B) utility for print requests
Represents a queue that is currently accepting new jobs. It toggles to Queue Stopped. When changing its setting you must specify how the queue should handle any job currently in process. Queues can stop:
About the Xinet Administration Interface for monitoring printer queues
If you have been granted proper permission, you will have access to Xinet printer and hot folder administration functions through a subset of the Xinet interview used by your system administrator. What you see there depends on the privileges you have been granted, which, with regard to printing, may include the following:
To gain access to the functionality, see Administrative privileges.
You should see Print/Hot Folders, and Queue Status information, although details depend on the privileges you have been granted and the configuration of your server.
Use the various tabs to locate information about and controls for queues. Depending on the way your administrator has configured your account, you may not have access to everything. If you do, you can check on Pending and Completed jobs, edit existing Print Queues and establish new ones, add and edit Spoolers that point to those Print Queues, and edit existing Hot Folders and make new ones.
If you have questions about any of these activities, use the Help link. It will open the pertinent section of the Xinet Administration Guide.
To return to your customary use of Xinet, click the Top Level link.
Setting Previewing for Low and High Resolution Assets
Macintosh users who have direct access to the server:
If you are using images that contain transparencies or if you only have remote access to the server, a PDF Image Replacement workflow may be better than a PostScript one. You’ll find more information about that beginning on PDF Image Replacement workflows.
Working with image proxies
What is an FPO?
A For Placement Only (FPO) image is a low-resolution view of a higher-resolution image which can be used to speed up document layout and printing setup, and in some instances, to achieve graphic effects that might otherwise fail at print time. The high-resolution image can be EPS, TIFF, etc. (For what kinds of images does the server create FPOs? lists all the graphic formats for which the Xinet server creates FPO proxies.) Inside the spoolers, the Xinet graphic production server automatically replaces the FPO with its high-resolution corollary. During the process of image substitution, the Xinet server can also automatically perform such actions as correcting color for a given output device, fixing problems with gradient fills and transparency, allowing use of image formats that desktop applications may not otherwise be able to handle, as well as optimizing the output sent to the RIP.
Creating an FPO
The Xinet server automatically creates low-resolution FPO images for all supported images in high-resolution volumes. All you have to do is scan a new image directly into a Xinet volume, save an image from an image editing application, or drag any other image file into a Xinet volume. The server automatically creates an FPO image in the corresponding FPO volume.
When you scan or drag an image into a high-resolution volume (in this example, wnv_vol), Xinet automatically creates a low-resolution FPO in the corresponding FPO volume (in this example, wnv_vol FPO).
High-resolution volume. Modification time reflects last changes to the high-resolution originals. Any changes made to the originals will automatically appear in the FPOs.FPO Volume. “For Placement Only” files are much smaller than the high-resolution originals. They are locked; changes (other than sizing, placement, etc.) to them must be made on the high-resolution originals. The Quark file, on the other hand, can be edited.
 
Using FPOs
When you copy an image in a Xinet high-resolution volume, Xinet automatically and quickly creates a low-resolution equivalent placement view inside the corresponding FPO volume. The server also creates custom icons when it is creating FPOs, and if your network administrator chooses to turn on the option, PICT or TIFF placement previews. Not all Macintosh applications use PICT placement previews, so your system administrator may or may not enable this option, depending which applications your site uses and how much available disk space there is at your site. The administrator may choose to enable the feature on a per-shared-disk basis, so all shared volumes at your site may not necessarily have this feature enabled.
If you want to change the images themselves, edit the high-resolution images to which the FPOs refer. The Xinet provides a number of shortcuts for opening high-resolution image files:
With FPO generation enabled on a volume, the server will automatically reflect any changes made to the original file in its FPO equivalent image. It is therefore possible for one person to edit the high-resolution original at the same time another person does page layout with its FPO—and, with Picture Wrangler keeping image links up-to-date, have perfect print results in the end.
To incorporate FPOs in your work, simply “import,” “link” or “get” an FPO image using the built-in image placement facilities of the Macintosh application you are using. The fact that you are using an FPO shouldn’t alter the way you use Macintosh applications. The server will apply any attributes you apply to the FPO (changes in size, cropping, tinting, skewing, etc. that are set in your layout program, as opposed to image-editing software) to the high-resolution version at print time.
FPO resolution
Most FPOs will be at a resolution of 72 dpi. You shouldn’t notice much difference in the way images look on your screen. Xinet software does, however, offer system administrators the option of setting up volumes which create FPOs at a resolution different than 72 DPI. Your system administrator can tell you whether you have other resolutions available.
For what kinds of images does the server create FPOs?
The Xinet creates FPO files (either EPS or TIFF) for images from a variety of formats. This makes it possible for you to incorporate some images in your documents, for example, Photoshop Native images in InDesign files, which otherwise you might not be able to use. Xinet creates FPO files for the following:
There may be instances, based on system administration options, when the server will not create FPOs for some files, e.g., the server may be optionally configured so that it does not create FPOs for vector EPS and/or PDF files.
File locking
FPO images
Images inside FPO volumes are copy-protected on OS X. Although you may change many printing parameters applied to those images through a layout application, you cannot change/save the actual contents of the FPO images directly. You must change the high-resolution corollary to change its FPO.
 
High-resolution images
The Xinet server enforces standard AppleShare file locking. Most applications will only allow one person at a time to edit an image in a high-resolution volume. The first person to open the image will have write permission. While another user may be able to look at the image at the same time, he or she will not be able to save a change to the image. (Photoshop presents a notable exception. See Use care when editing Photoshop files for details.
Renaming, moving or deleting images
The Xinet server automatically generates low-resolution FPOs for any image you place in a high-resolution volume, giving the FPO image the same name as its high-resolution corollary. At a later time, if you change the name of the high-resolution image, the FPO version will reflect the same name change.
On OS X systems, FPOs are copy protected. If you want to change names or locations of FPOs, make those changes in the high-resolution volume.
You may also drag images from the high resolution volume to the Trash. Doing so also removes the FPO corollaries from the low-resolution FPO volume. The converse is not true, however; because they are locked or copy-protected, you cannot drag FPO images to the Trash.
Time stamping
To synchronize time across the work-group, OS X users should make use of Network Time Protocol (NTP) technology. (See www.ntp.org for more details.) NTP allows your Macintosh to periodically synchronize time with a central server. To make sure you are doing so, check your settings in your System Preferences’ Date & Time dialog. Make sure that the Set Date & Time automatically option is engaged, as shown below.
Setting the date and time (OS X)
If your Xinet server provides NTP services (check with your system administrator), you probably want to direct your Macintosh to those services. If not, everyone in your work-group should choose the same server from one of Apple’s default services in the pop-up menu.