Viewing and Printing ADS Articles


When retrieving a document from the ADS article server for printing, please make sure that the software and hardware on your system are capable of handling the selected format. It is your responsibility to make sure that the data sent to the printer is correctly transmitted and interpreted.


Introduction

Documents are available from the ADS article server in different formats and at different resolutions to accomodate our users' needs. The high resolution documents (600 dpi) are considerably slower to print than the low resolution versions (200 dpi), but will give superior results, especially on plots and plates. In addition, the high resolution files are larger than the corresponding low resolution ones, and some display programs or printers may not have a large enough spooling area or physical memory to handle them. In order to decide which version of the article you should select for viewing and printing, you need to take into account the capabilities of your system and the network bandwidth available to you.

When an article is selected for viewing from the ADS article server, our software sets the document MIME type to match the format you have selected. For instance, if you are downloading a PDF file, the document's MIME type will be application/pdf. Your browser will detect this MIME type and will run the application that has been configured to handle it (e.g. Acrobat Reader). For the most part, downloading documents for the purpose of viewing them prior to printing should work seamlessly once the appropriate helper applications have been installed. The section named Document Formats below describes the different file formats available from the article server and which software applications can be used to display them.

When an article is selected for printing from the ADS article server, the document will be returned with a particular MIME type (application/remote-printing), irrespective of what article format was selected. By default, your browser will not be configured to take any action on documents of this type, and it will prompt you instead asking what should be done with the article being downloaded. The options available to you are usually to either save the document to a local file or open it with one of the applications available on your system. Either way, you will have to make your choice before the article downloading commences. The section named Printing Documents below describes how to automate the process of downloading and sending files to your local printer.

If you find problems with the setup described in this document, please make sure to also check the Troubleshooting section for suggestions. Feel free to send us your comments and questions if your problem persists.

Document formats

Currently all ADS articles are made available in the following document formats: PDF, PostScript (level 1 and level 2), PCL, TIFF. In terms of document size and portability, both PDF and PostScript level 2 documents are to be preferred over the other formats, since we can achieve excellent compression of the article images by using the internal compression schemes supported by the two formats. PDF files have the additional advantage of allowing binary encoding of the image data, which makes them 20% smaller than their PostScript counterpart. Currently these two formats are the only ones that can be used to retrieve high-resolution full-text articles. Images stored in PCL files are also internally compressed, but not as efficiently, and are available at a maximum resolution of 300 dpi. Documents in PostScript level 1 format yield the biggest file size, and often require large resources of printer memory and spooling space to successfully print. Because of these limitations, we strongly encourage you to avoid selecting this format if at all possible. TIFF is supported as an output image format when retrieving individual pages only (both at high and low resolutions).

PDF
This format is suitable for viewing with a PDF viewer such as Acrobat Reader (all platforms), gv (UNIX), or gsview (MS-Windows).

PDF (Portable Document Format) is a popular document description language developed by Adobe Systems. Unless a PDF viewer is already provided on your system, you will need to install and properly configure a helper program in order to be able to display and print PDF files. While this may sound like a limitation of PDF, the fact that viewers and printer drivers exist for all popular platforms make this a very portable format. Furthermore, because of the advanced compression schemes and binary support built into PDF, documents in this format will yield the highest compression.

Postscript level 2
This format is for printing PostScript printers capable of understanding level 2 postscript (most of them nowadays) or for viewing with a display PostScript program such as gv and ghostview (UNIX), or gsview (MS-Windows and MacOS).

The PostScript page description language was also developed by Adobe Systems, and can be considered a precursor to PDF in many respects. The advantage that Postscript files have over PDF is that most department-size printers today are capable of printing postscript files quite efficiently, so there is no need for an external viewer or printer drivers when hardcopy output is desired. These files should successfully print on any of the modern printers supporting the Adobe PostScript level 2 language features, but some problems have been observed with print engines that don't use the Adobe PostScript interpreter. Postscript level 2 supports the same compression schemes that are used in PDF files, but since it requires ASCII rather than binary encoding of the image data, these files are approximately 20% bigger than their corresponding PDF files.

PCL
This format is for printing on PCL-compatible printers such as the HP deskjets and compatibles. PCL Files may be viewed or printed under Windows 95/98/NT on a non-PCL printer with a freeware product from Page Technology Marketing, Inc.

PCL is a low-level page description language understood by most of the printers available nowadays. The PCL documents produced by our article server abide by the PCL3 language specification as developed by Hewlett Packard. PCL files should successfully print on a variety of both low-end inkjet printers (such as the HP deskjets and compatibles) as well as the higher-end laser printers (such as the HP laserjets 4/5/6 series and compatibles).

Documents delivered as PCL files are internally compressed, but not as efficiently as in the case of PDF and Postscript level 2. Therefore, when downloading files in this format, we reccommend you enable the option to compress the file using gzip when retrieving it.

Postscript level 1
This format is for printing on older PostScript printers which only understand level 1 Postscript, or for viewing with any of the postscript display programs listed above.

Please note that due to the lack of internal compression in postscript level 1, documents in this format will tend to be quite large and print very slowly, so we urge people to avoid using this format if at all possible, and instead select a more efficient format such as PDF, coupled with a proper viewing/printing application.

TIFF G4
This format is for retrieving individual pages as TIFF (Tagged Image Format) images and displaying them with a an image viewer such as xv and ImageMagick (UNIX), Imaging for Windows (which comes with Windows 95/98/NT), or NIH Image (Mac).

Printing Documents

If you find yourself retrieving and printing ADS articles all the time, you may consider setting up your browser so that downloading and article and saving it to disk or printing it take place automatically. In order to do this, you will need to map the MIME type of the data returned by our server to the local printing program on your system. This sounds more complicated than it really is: most browsers (including Netscape Navigator and MicroSoft Internet Explorer) provide menus that allow the user to define the application to be run for each given file type. For Netscape 4.x, the menu is available under ``Edit -> Preferences -> Navigator -> Applications.'' Once you have found the proper menu for your browser you can create (or modify) the following entry for the MIME content type application/remote-printing:
Description:    Remote Printing
MIME Type:      application/remote-printing
File extension: .prn
Application:    (select OS-specific application or select "Save to File")
Selecting the ``Save to file'' option in the menu above will cause all article documents dowloaded from our site to be saved to disk first. You can then view them or print them using the appropriate program depending on the document format as explained in the section ``Document Formats'' above. Alternatively, you may choose to have a helper application execute automatically when a document of this MIME type is downloaded. In this case, you should select ``Application'' from the above menu and then fill in the proper command depending on the computer platform you are using. This command typically is a procedure that feeds the data downloaded from our server to your local printing command, and in general depends on the operating system of your computer. Some examples of popular operating systems and relative printing applications are:
  • System V-based UNIX systems (e.g. Solaris):
    lp -c %s
  • BSD-based UNIX (e.g. Linux):
    lpr %s
  • Microsoft Windows (3.1, 95, 98, NT):
    prfile32 %s
    (this assumes you have downloaded and installed the freeware program
    printfile as detailed in the Printing Solutions page).
  • There are additional options that can be used to view or print documents retrieved from our system, which can be more or less useful depending on your setup. Feel free to send us any comments you may have about any other suggestions you may have on this topic.

    Troubleshooting

    If you are having trouble printing articles, please make sure you have checked the following:


    Last updated: 26 June 2000