Adobe InDesign CS/CS2 Breakthroughs [Electronic resources] نسخه متنی

Touchy Transparency

Where's the Transparency?

A few of the page icons in my Pages palette are showing that gray-and-white checkerboard pattern indicating there's transparency on the page. As far as I know I didn't set or place anything with transparency there, so where is this coming from? I can't tell by looking at the page, everything looks 100% opaque to me.

Many people don't realize that adding a drop shadow or using feathering adds transparency. Similarly, a PSD, AI, or PDF file that you imported may include transparency without you knowing it. To figure out where the transparency is, open the Flattener Preview palette (Window >Output > Flattener Preview) and choose Transparent Objects from its Highlight menu. Any object on the page that has transparency applied will appear with a red overlay, all the other objects will appear as a light screen of gray (Figure 8-11). Change the Highlight back to None to turn off the preview.

Transparency Harms Innocent Text, Story at Eleven

Even though the drop shadow I've added to a rotated image doesn't touch the column of text it's next to, it appears to have affected some of it. A vertical strip of the text appears bold, just a small subsection nearest the image, in the proof print I made on my laser printer.

InDesign creates a phantom, rectangular bounding box surrounding every object containing transparency, and everything on the page that ends up inside the bounding box is affected by the transparency being flattened unless it's above the transparent object in the stacking order. Bounding boxes are never rotated if the image is rotated, the bounding box just enlarges to enclose it completely. In this case, it sounds like the text was below (stacking order-wise) the image and that "bold" strip fell within the bounding box area.

The text becomes "bold" as a result of InDesign converting the text to outlines. Since you printed to your local printer, InDesign probably applied the default Medium Resolution preset for the Transparency Flattener (check the Advanced panel in the Print dialog box to see and change the Flattener preset).

There are a few ways to fix this:

Transparency and Your Print Vendor" on page 220.)

Print with the High Resolution Transparency Flattener preset.

Select the text frame and move it higher in the stacking order than the drop shadow box, to its own layer at the top of the layer stack if necessary. This is probably your best bet, because even if text lies right on top of a drop shadow, it won't be affected by flattening. You can verify this in the Flattener Preview palette, set to view All Affected Objects (Figure 8-12): The text appears light gray (unaffected), while the object and its shadow under-neath appear with a red overlay (affected).

On occasion, you'll get bold text around transparency even if the text is on top of the transparent object. As far as we know, this only happens when you export a PDF file from InDesign and print it from Acrobat 6. It's actually an Acrobat bug, but the only solution we know of is to turn off the Overprint [Black] Swatch at 100% option in the Preferences dialog box (in the General panel in CS and the Appearance of Black panel in CS2). Now recreate the PDF and it should work properly.

Remove White Boxes Behind Drop Shadows

The drop shadows look perfect in InDesign and in our internal PDF proofs, but when my printer sent over the color proof (created from my InDesign file), every item with a drop shadow had a horrible white box behind it. He said that InDesign's drop shadows were "flaky" and that I shouldn't use the feature.

InDesign isn't the flaky one here; it's your printer! InDesign's drop shadows and other transparency features are generally only "flaky" if you use older or quirky equipment to output the data. The majority of print vendors do use up-to-date hardware and software fully compliant RIPs that understand how Adobe software handles transparency and have no problems with drop shadows. Trust us, if this weren't true no one would be using the feature! (See the sidebar, "Transparency and Your Print Vendor" on page 220 for more info to help your current vendor or to find a new one.)

If your printer uses a composite workflow their RIP does the separations ask them to check that the RIP honors overprinting instructions in the file. Some backend equipment is set to ignore overprinting by default, and drop shadows (and other transparency features) depend upon it.

What's that Thin White Line?

In Acrobat, with Overprint Preview turned on, I can see faint white lines or rectangles in the PDF I'm about to send to my print vendor. They appear to define the rectangular edges around certain objects that have drop shadows or other transparency effects. What are they? Should I be worried?

Before you get concerned, zoom in very closely to see if they disappear. If they do, or if they stay the same tiny size as you zoom in, it's just a screen artifact and won't appear on the printout. You can typically get rid of them on Screen by turning off the Smooth Line Art and/or Smooth Images options in Acrobat's (or Reader's) Preferences.

Warning

If you're seeing white boxes behind drop shadows or other transparency effects in your internal PDF proofs (Figure 8-13), turn on Overprint Preview from Acrobat's Advanced menu, or re-export the PDF with Acrobat 5 (or higher) compatibility.

If you're not seeing them, but your clients are when viewing your soft proofs in Reader or Acrobat, ask them to turn on Overprint Preview. Depending on which version of which PDF viewer they're using, the command will be in their Advanced or View menus; or in Reader's Preferences in the Page Display panel. If you have no idea which version of Reader or Acrobat they might have and you'd rather not encounter the problem at all, give them a for-proofing-only PDF that you've created with Simulate Overprint turned on in InDesign's Export to PDF dialog box.

Finally, if you're seeing white boxes behind drop shadows on your inkjet printer output, export the layout to PDF with Acrobat 5 or later compatibility, open it in Acrobat, and choose Print As Image from Acrobat's Advanced options in its Print dialog box.

Any lines that don't go away may be due to stitching, an Adobe term for a line that sometimes appears at the point of transition from a vector area to a rasterized area, when the rasterization is a result of the transparency flattening process. Stitching artifacts were occasional problems with InDesign v2 but became much more rare in InDesign CS. (And we hope will become virtually extinct with CS2.) Some manufacturers' RIPs are more prone to stitching than others because of how they interpret data, too. In other words, what creates a visible artifact on one printer (or one vendor's platesetter) may not on another.

If you're in charge of flattening the transparency, you should always use the High Resolution Flattener preset in the Print or Export PDF Options dialog box, which greatly reduces the chances of this happening. But the best solution, as explained in the sidebar earlier in this chapter, is to leave the flattening to your print vendor. Give them the native InDesign file or a press-ready PDF with live transparency (Acrobat 5 or later compatible), and ask for a composite color proof of the RIPped file.