MathType EPS Color Separations with PageMaker and PrePrint

The information in this document applies to:

There is a conflict between PageMaker and PrePrint in the way color is handled for EPS files. PageMaker has its own color scheme, in which the user can select objects and assign them a color. When printing separations directly from PageMaker, color information inside any included EPS files is ignored, and PageMaker's own color settings are used.

PrePrint, however, ignores PageMaker's color settings and honors the EPS object's intrinsic color information. Because current versions of MathType for the Mac don't support color directly, EPS files created with older versions of MathType will use whatever color the current PostScript pen is set to when it executes our EPS instructions. The result is that PrePrint doesn't filter MathType's EPS files out of any layers, and so they end up printing in all separation layers.

MathType 3.x

We have designed MathType 3.0a incorporate the setgray command within each EPS file. To invoke this capability open the MathType Preferences file with a text editor (e.g. SimpleText), and enter the line EPSSwitches = 1 in the [General] section. This will cause MathType to insert the PostScript command 0 setgray into EPS files, which will make PrePrint place MathType equations only in the Black layer.

If you need to change between this setting and an EPS setting that does not use the setgray command, we suggest that you save a duplicate Preference File without the setgray command.

MathType 1.0 and 2.0

There is a simple workaround, but it has a limitation. There is a PostScript command, setgray, which sets the shade (from white to black) of the pen. If this is inserted at the beginning of the PostScript code inside our EPS files, when PrePrint prints separations it will notice this command and allow us to appear only in the Process Black layer. If this is desired, then the .sep file that PageMaker produces can be opened in a text editor and the appropriate line (0 setgray) can be inserted into every MathType EPS section (there will be one for every equation in the PageMaker document). Insert the line:

0 setgray

Following the line:

/MTsave save def 30 dict begin

Remember you'll have to repeat this procedure every time you modify the PageMaker document and produce a new .sep file.

Another approach to this workaround is to modify the EPS strings in MathType itself, so that all new EPS files produced will have this extra command included. This can be done with ResEdit, a program that allows the user to edit resources found in a Macintosh file (these include menu items, dialog boxes, and strings of characters which MathType may use in dialogs, printouts, or in saving files). Any editing should be done on a copy of MathType (in case of accidents!). To do this, open MathType in ResEdit, and open the STR# resources. Open resource number 29551, and scroll so that string number 45 is visible (about halfway down). This contains the EPS header. Append the following two lines to the string (note that two % characters are required here for every % character that will appear in the header):

%%%%EndProlog
0 setgray

Then quit ResEdit and save the changes to MathType. To check the change, run the modified version of MathType and create an EPS file with no graphic. Then open it with SimpleText and verify that the added lines follow the %%EndComment line. Be careful if you have two copies of MathType on your hard disk; if you start MathType by double-clicking a document or by double-clicking an OLE equation in Word, it's not always obvious which version actually is running. The copy of MathType with the newest date will be the one that starts.

Note: We recommend adding the EndProlog line after the EndComment line in the EPS header, as some programs (including PrePrint) look for this comment explicitly when opening an EPS file directly. If you want to open MathType's EPS files directly in PrePrint (we're not sure why you would), you will need the EndProlog line. If you are placing the EPS files into PageMaker and then producing the .sep file for PrePrint, the presence or absence of the EndProlog comment doesn't seem to matter.

If you do not want to place the MathType equations in the Process Black separation, some color PostScript commands must be placed inside our EPS files. This too could be done in the .sep file that PageMaker produces. This requires further research.

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