Illustrator CS white bounding box in eps files

[elizabeth_yugi@adobeforums.com]

I am working with Illustrator CS, Mac OS 10.3.3

I recently upgraded to the CS Suite. Now, though, when I save a file from Illustrator CS as an eps file, and then place that file in InDesign CS, it comes in with a white bounding box. (If saved as an "ai" file it does not have the box. However, the ai file brings in all four process colors even if it is a one or two PMS color file. The eps file brings in just the two PMS colors, which is desirable.) Can you tell me how to get an eps file without the white bounding box showing up when eps file is placed in InDesign?

Thanks.

[Doug_Katz@adobeforums.com]

Huh? Why would the .ai file bring in ANY colors that aren't in it? Not sure I follow that.

I believe the .eps will always have a white bounding box as it is a flattened file.

[John_Kallios@adobeforums.com]

The blank cmyk channels are there in a .ai file and nothing can be done about that.

As to the eps issue, there are two main issues that cause this.

1st, the white box preview (when saving with a pict preview) is false. When placing into InDesign, either turn on overprint preview or high resolution preview. If the white disapears, then this is the problem and solutions are to save as .ai or pdf file (which have the blank cmyk channel issue) or save with a transparent tif preview. The first issue is only a screen preview issue and will output correctly on postscript devices.

2nd Is that you have transparency in the document. Transparent pixels over nothing when saved to eps is seen as WHITE when placed into a dtp application. Saving with transparent tif preview will result in a FALSE preview. Turn on overprint preview or high resolution preview when place in InDesign. If those transparent areas turn white, then that is your problem. This problem also can be a screen preview problem (if saved with transparent tif preview) but the white WILL show when printed. Solution is to save out of Illustrator in a format that supports transpareny. .ai or 1.4+pdf. (which have the blank cmyk issue. No getting arround that)

[Doug_Katz@adobeforums.com]

JK, I want to get clearer on all your points above:

1) So native, CMYK .ai files always "travel" with 4 process channels (plus any spots), even if one or more (or all) of them are emty? In other words, the application doesn't "self-purge" unused channels? If I have that right, I'm very glad you taught it to me. Does this mean, once placed in a layout application, those blank channels will output blank? Or will they simply not output?

2) I learned from YOU that the .eps format is flat out of AI. Are you saying in your last two points than an .eps DOES, in fact, have a transparent "background" (I mean, EVEN when "transparency" in the "modern sense is NOT used)? In other words the areas of the art in an .eps that DON'T have painted objects (the "white spaces") WILL be transparent when placed?

[John_Kallios@adobeforums.com]

Point 1) Yes, the cmyk channels are always there due to the file being based upon pdf. PDF files ALWAYS carry the cmyk channels.

Point 2) Yes, ALL and I mean ALL eps files are FLAT.

Flat vector objects are different than flat raster objects.

(You really do not have to do the proceeding, it is just used for a visual reference.)
Make a circle filled with any swatch color. Select any ONE anchor point and delete it so that you are left with a open filled semi-circle.

Save as eps file with opaque tif preview.

The preview will show white where there is no image in the bounding area.

Save as eps with transparent white preview and the preview will show the no fill areas as transparent.

Both eps files contain the same image which is ONLY the filled semi-circle. There is NO image in its surrounding bounding area. Picture cutting out a semi-circle out of a piece of contruction paper. That is what a vector piece of artwork is. (besides being based upon mathamatical equations and resolution independant) There is nothing in its bounding box. No white pixels and no transparent pixels.

The preview is a additional file within the eps file that is pure raster. This is only used for preview purposes.

If you made that same circle in Photoshop, then it would be raster. (assuming you did not use any vector to create it in Photoshop) Barring bitmap mode (which is sort of a exception to the rule) raster objects always contain pixels that fill the ENTIRE bounding area. Whether these pixels are white or transparent, they always fill the entire rectangular bounding area. (I am leaving clipping paths out of the equation)

A flat raster is similar to painting to a piece of white paper. A transparent raster is similar to painting on a piece of glass.

That is background info and I am sorry for jumping around on this topic.

Eps files are containers for raster and vector info. The eps format understands NOTHING in vector.

Eps format understands White pixels.

Eps format does not understand transparent "pixels" regardless if the "pixel" is raster or vector. It will force the transparent portion to be white. The of when the eps is created, it goes through a fog bank. The transparent glass foggs up appearing white while there is nothing to fog up with pure vector that does not contain transparency.

Did I confuse the issue more?

[Dee Holmes]

Very good examples, John. How enlightening.

[Doug_Katz@adobeforums.com]

Wonderfully clear.

So at output from a layout program, any VECTOR .eps (e.g., a 100% vector .ai file saved as .eps) will ONLY output the OBJECTS in it. For OUTPUT purposes (not screen preview) all the "space" between the objects and the .eps bounding box simply isn't "seen," by the output device.

So, in EFFECT, vector .eps files DO have "background transparency."

[Dee Holmes]

As far as I understand, Doug, it's the embedded, linked, and flattened objects to look out for.

[John_Kallios@adobeforums.com]

I would just steer clear of that use of the word "transparency" to describe it because to me, the absense of a element is not transparent. It just does not exist.

Vector can also contain transparency but when saved to eps, it is white.

[Dee Holmes]

I do not use "transpareny" at all since I'm usually working with spot colors. But we do deal with some process files that have transparency. Usually gives us a problem when outputting. If fonts come out thick and thin then I recomend flattening just the fonts. Because our process work also has spot colors usually. Flattening just fonts usually works for us. Is this the correct proceedure?

I'm in prepress by the way, so we aren't creating our own files.

[John_Kallios@adobeforums.com]

Dee, check out this pdf of the Studio Exchange. <http://share.studio.adobe.com/axAssetDetailSubmit.asp?aID=7545&back=http%3A%2F%2 Fshare%2Estudio%2Eadobe%2Ecom%2FaxBrowseSubmit%2Ea sp%3Ft%3D56>

Though the pdf referrs to InDesign, Illustrator has the same issues when it comes to live text under transparent elements.

[Doug_Katz@adobeforums.com]

JK, thanks once again. I understand your caution about the word transparency: The non-object areas within the bounding box of an .eps are not transparent. They simply are not... the difference between an invisible something and a nothing. I only meant that vector "nothingness" seems to function VISUALLY in much the way raster transparency functions.

[elizabeth_yugi@adobeforums.com]

JK, thanks for your help. Going to InDesign View:Overprint preview solved the problem!
1. You also mention high resolution preview....where is that?
2. If I do save a file as "ai" and place in InDesign, the preflight will show the four process colors and any pms colors in the ai file. Can the printer ignore the process colors that are not used or would I be charged for outputting plates for those colors?

[John_Kallios@adobeforums.com]

Any printer who does not ignore blank cmyk channels should be flogged, tarred, feathered and made funny faces at.

High Quality Display located at:

Obeject>Display Performance>High Quality Display.

or

Control click on the item (right click if you use a two-button mouse) >Display Performance>High Quality Display.

[elizabeth_yugi@adobeforums.com]

JK,
Thanks so much for your help!

[Michael_Gianino@adobeforums.com]

Hi, everyone. I've been reading this thread, but it hasn't applied to me until just now. My shop uses OS9, Illustrator 9 & 10, Quark 4.11 and PageMaker 6.5 & 7. Someone just sent us some Illustrator CS eps's to place into page layout, and they all have the white background (that doesn't print, but it does make placement a little more difficult). They are made of straight stroked lines, filled boxes and circles and very little type. Nothing too complicated.

I can't open the Illy CS files, so I don't know if there actually is a white bounding box in the files, but the white portion of the preview is larger than the actual image by around 30%, so it's possible. I also don't know if they were done in Mac or PC.

My question: is this just an issue of which preview they chose when saving the files, or will the white background always be present when using CS eps's in OS9 Q and PM?