HELIOS ImageServer User manual


4 Setting up the OPI server with EtherShare Admin
4.1 General remarks
The following chapters only explain OPI related dialogs. For an overall description of the EtherShare Admin program, please refer to the EtherShare documentation.
The EtherShare Admin program lets you specify various parameters that are required for using OPI. Some specific parameters, however, can be set or changed manually using UNIX commands. For advice on how to handle these commands, please refer to the reference guide of this manual (see 6 "ImageServer utility programs").

Important: You may not skip the administration before using OPI because, by default, OPI is not active on printer queues and color matching has to be activated explicitly as well.

Note: The following chapters describe the effects single settings will have. In A 1 "About OPI settings, typical workflows, and conflicts" you can see how different settings influence one another and how the software behaves if application specific OPI settings intervene.

4.2 Starting the Admin
Your EtherShare configuration has not been modified during the installation of ImageServer 2.5. You can now start the EtherShare Admin program on any Macintosh client to set up OPI.
-> Mount and open the "HELIOS Applications" volume and double-click EtherShare Admin. The copyright dialog welcomes you to the Admin program (Fig. 4).
Fig. 4: Starting the EtherShare Admin program

, Select File and Login from the Admin menu, login on your server, and make sure that you have sufficient access privileges to modify the configuration.
4.3 OPI server settings
With the OPI Server Settings dialog you define general OPI settings. These settings are valid for all layout images that are generated on your OPI server.
-> Select Lists and OPI Server Settings from the Admin menu to open the dialog shown in Fig. 5.
Fig. 5: Defining preferences for the OPI server

Note: The Revert and Save buttons remain disabled unless you change anything in the dialog.

ICC-Profiles
Volume
Color matching with ImageServer 2.5 is based on ICC-compatible profiles. All profiles that you want to use must be stored in a central repository. Setting up ICC Profile Volume tells the server where to find the profiles.
The pop-up menu includes two different options:
Layout Color:
This item serves to select a color space for all layout files that are to be generated on the server, and at the same time defines an ICC profile which is to be used for color matching the layouts.
You can choose between four different options:
CMYK
Default
Profile:
The CMYK default profile is used whenever OPI has to transform an image from another color space into CMYK or vice versa and if - in a situation like that - a CMYK output (printer) or input (image) profile has not been defined explicitly. If you select EBU RGB from the Layout Color menu, for example, and your high-resolution image is a CMYK image, OPI has to perform a transformation from CMYK into RGB during layout generation. If your high-resolution original has no image profile, OPI will use the CMYK Default Profile. The pop-up menu lets you select either Euro or SWOP.
Layout
Quality:
Your layout quality may be either Excellent or Standard.
Layout Compression
Layout images do not inherit any compression from the high-resolution originals. You have to choose a compression mode, if desired. There are three possible options which can be - even more than one concurrently - selected from the checkboxes:
Clipping paths
Additional Channels
Default
Monitor
Resolution:
This item serves to define the default monitor resolution for your layout files. Monitor resolutions usually range from 72 to 100 dpi.
Default
Print
Resolution:
EPSF files contain a monitor preview and a printable preview of the respective image. It is, therefore, sensible to allow you to define for your layout images two different dpi values. You can e.g. enter 72 dpi monitor resolution and 96 dpi print resolution if you print your documents with EPSF layout images and want to achieve a printout quality better than 72 dpi.

Note: For files that have only one preview (for printing and monitor display) the OPI software compares the Default Monitor Resolution to the Default Print Resolution and uses the higher value as layout resolution. This applies e.g. to TIFF images.

Layout name:
Here, you can decide whether you want to apply the ".lay" extension to all layout files or whether you want to collect your layout files in a separate folder and skip the extension.

Note: Folders may be configured separately, that is you can define for all layout images in a specific folder several parameters (e.g. resolution or color space) that differ from the default settings on your server (see 5.3 "Defining folder specific OPI settings" for details).

Layout Delay:
In this field you can define the time in seconds before the layout creation process is started by the OPI server. The purpose is to prevent layout files being generated for temporary files.

Important: Please note that all above mentioned server settings are only applied to future layout files. If you want to update any existing layouts accordingly, you have to re-generate them. For that purpose you can either open and save the high-resolution original image file once again, use the HELIOS "touch" program (see 5.5 "Refreshing layouts using the "touch" program"), or use the "opitouch" program (see 6.3 "The "opitouch" program").

Image Search Paths -
In some situations, you may want to move your image files to another volume or folder. You can help OPI find these images for printing if you define search paths that lead to the locations you usually use.
There are, in principle, no limits as far as the number of search paths is concerned. You can save time, however, if you make sure that the locations you use very frequently are checked first.
Pressing the Image Search Paths - button will open the Image Search Paths window displaying the paths that are already defined (Fig. 6). You can delete any of these paths or add new ones. The Add - button opens the dialog that serves to select new paths (top right corner of Fig. 6).
Fig. 6: Defining image search paths

Note: Detailed explanations on how ImageServer deals with image search paths are given in 3.7 "How the ImageServer finds and replaces image files".

4.4 Volume settings
Some OPI settings are volume-dependent. To edit the settings for a specific volume do the following:
-> Select Lists and Volumes from the Admin menu to display the list of all your EtherShare volumes.
-> Double-click the volume you want to set up.
Fig. 7: Defining volume-dependent OPI settings

The dialog shown in Fig. 7 will display all EtherShare specific settings you have entered when defining the volume (for advice on how to define a new volume, please refer to the EtherShare documentation). There are only two items in the dialog that are important for the configuration of OPI, namely the checkboxes Create Layouts and PC Layouts.
Create
Layouts
This checkbox serves to activate automatic generation of layout files. As soon as you switch on Create Layouts the OPI server will generate a low-resolution layout file of every high-resolution image file you save on this volume. The generation of layouts will take a few moments, it starts after a user-defined time delay. This is - by default - after 30 seconds delay (compare Layout Delay: above in this chapter).
PC Layouts
File characteristics are slightly different on Macintosh and Windows computers. You have to switch on PC Layouts if you want OPI to always generate PC-compatible layouts - even if the original high-resolution images are coming from a Macintosh computer; OPI generates layout files always according to the PC Layouts checkbox in EtherShare Admin's Volume settings (compare Fig. 7).

Note: Since the Macintosh is also able to recognize PC-compatible layouts, make sure to always have checked the PC Layouts checkbox in the EtherShare Admin when working on a volume shared with PCShare (see also A 4 "Notes for PCShare users").

Please note that working with PC Layouts would mean that:
4.5 Printer queue settings
Some OPI settings are only meant for printing and have to be set up for every single printer queue.
Printer queue settings for EtherShare and ImageServer are in two different dialogs.
-> First of all, you should display all your printer queues. Select Lists and Printers- from the Admin menu to open the window shown in Fig. 8.
Fig. 8: Displaying the "Printers" list

Then, if you want to define additional printer queues for use with the ImageServer, highlight a printer from the list and select File > New from the EtherShare Admin menu to open the dialog shown in Fig. 9. Detailed instructions on how to configure this dialog are given in the EtherShare documentation.
Fig. 9: Defining an EtherShare printer queue

Note: It may be helpful to define an "Error Queue" for your OPI printer queue (Fig. 9). This EtherShare feature allows you to save print jobs that have produced an error message (e.g. because of missing image files). After solving the problem, the print jobs can be started again directly from the error queue. For details please refer to the EtherShare documentation.

Once you have defined EtherShare printer queues, you can now set up OPI for each of these queues.
-> Highlight a printer from the Printers list and then select Printer > OPI/ICC Settings from the Admin menu to open the dialog shown in Fig. 10.
Fig. 10: Defining OPI settings for a specific printer queue

OPI Active
The OPI Active checkbox activates OPI for this specific printer queue and at the same time enables the OPI/ICC Settings dialog. If you switch off OPI Active, you cannot change any settings in the "OPI Printer Setup" section.
Print Layout Images
With Print Layout Images, the printouts from this specific printer queue will only contain layout images. The copies of the images - which you have used for layouting your document - will be sent to the OPI server and then be replaced by the layout files instead of the high-resolution originals.
Replace
Images:
Replace Images = Layouts is the default resolve option. If this setting is activated the OPI server will only replace layout images during printing. High-resolution originals you may have placed in your document, will not be replaced. In case you want the OPI server to replace all images during printing (e.g. if you want to use the Omit - options in the print dialog) you should switch to Replace Images = All (see also 5.7 "OPI print options - include or omit images").
Check Images
If you activate Check Images, the OPI server will try to find all images that are included in a print job. If any images are missing, the job will be stopped, and issue an error message for every missing file. The strategies the OPI server uses for locating images, are described in 3.7 "How the ImageServer finds and replaces image files". If Check Images is not activated, single images may be missing on the printouts.
Check Fonts
The Check Fonts command will induce the OPI server to stop the print job and issue an error message if the current print job contains any fonts that are not available.
Down-
sampling:
The Downsampling item serves to define a uniform output resolution for all raster-based images - no matter whether you print layout images or high-resolution originals. If the resolution of a given image (e.g. 300 dpi) is higher than the value in this dialog (e.g. 222,30 dpi in Fig. 10), the OPI server will apply the value you have chosen for downsampling and then re-calculate and scale the image accordingly. Images with a resolution smaller than the value entered in this dialog, will remain unchanged because increasing the resolution automatically decreases the dimensions of an image. This would entail upward scaling and lead to a loss in quality.
The Downsampling pop-up menu contains a number of dpi values (running from 18 to 360 dpi) and the PPD Default option. If you select PPD Default the OPI server will use the dpi value that is stated in the PPD file. Selecting None from the list will switch downsampling off. Every image will then be printed according to its particular resolution.
There are efficient compression methods you can apply to the high-resolution images. Depending on the image format there are different types of compression that can be selected from the following pop-up menus. This considerably reduces the size of the PostScript printing data:
Bitmap:
The CCITT Group 4 compression is the best lossless linework compression available and can easily reduce linework files up to 50 times. It can be used with PostScript Level 2 or higher printers.
Monochrome:
Color:
The ZIP compression, which is compatible with PostScript 3 compatible printers, is the best lossless continuous tone compression. Compress works with PostScript 2 and 3 and has good compression results. JPEG (Low Quality, Medium Quality, High Quality, Maximum Quality) compression will always lose some image details but offers the best data reduction, it is supported with PostScript Level 2 or higher.
Check
ICC Profiles
for Pictures
Activating Check ICC Profiles for Pictures will induce the OPI server to check whether all image profiles that have been tagged to any of the image files are available. The server will automatically stop the print job if a single profile is missing and issue a corresponding error message. If this option is not active, OPI will execute all print jobs and use standard profiles for color matching, whenever the correct profile is missing, unless the input color space is the same as the output color space, e.g. Image CMYK = Printer CMYK.
Default
Printer Profile:
The Default Printer Profile item lets you choose the correct profile for your output device and, at the same time, serves to switch on color matching for this printer queue. The
pop-up menu contains four different options.
Default
Proof Profile:
This item will only be available if you have selected a default printer profile. Here, you can select the correct profile for your proof printer.

Note: It does not make any sense to select a proof profile if you have chosen Lab D65 from the Default Printer Profile pop-up menu. In that case, you have not yet specified your output device and thus cannot simulate it with a proof printer.

PostScript 3/DeviceN:
The PostScript 3/DeviceN Output checkbox should only be selected if you print to a PostScript 3 device with in-RIP separation. The PostScript output of PDF original files will be optimized to use the PostScript 3/DeviceN features. This applies for Hexachrome® printing, colorized images (Duotone), etc. In a future version of ImageServer DCS 2 files containing spot colors will be converted into DeviceN. When printing host-based separations with applications like QuarkXPress, this feature must be turned off, otherwise the output will lead to unexpected results.
4.6 Using the Admin printer log file to check OPI activities
You may use the EtherShare Admin program for both setting up OPI (before printing) and watching OPI (after printing). In fact, the printer log files contain comprehensive information about how OPI has handled the images included in a given print job.
-> Select Lists and Printer Log File from the Admin menu to display a list of your print jobs (compare Fig. 11) and double-click one of the jobs to open the log file.
Fig. 11: Selecting a specific printer log file

This log file will contain various messages that describe the respective print job. Some of the messages are OPI-specific. Fig. 12 shows an example of a printer log file. The OPI-related messages in this file inform you about -
Fig. 12: Contents of a printer log file

For further information about EtherShare log files, please refer to the EtherShare documentation.

© 2002 HELIOS Software GmbH