Our second meeting was held at Capps Digital from 6:30 pm to 9:30 pm — with pizza!
Gary Adcock, a Chicago-based digital artist and technology trainer who spends his time creating digital magic and evangelizing technology for clients such as the Dave Matthews Band, Target, CNN, Leo Burnett, NBA Entertainment, Pepsi, Sony, and Sears
James Wamser, Director of Training at Sells Printing, New Berlin, Wisconsin, where they’ve been outputting InDesign files since 1998 (alpha builds) and, since 1999, working for customers such as Trek Bicycle and Chicago Bar. They’ve won numerous awards, including the Award of Excellence from the Printing Industries of America and the Award of Excellence and Certificate of Merit from the Printing Industries of Wisconsin.
Matt Phillips, a member of the InDesign engineering team at Adobe, who specializes in the printing architecture of InDesign
From Gary
Exporting PDF from an InDesign page using transparency
Gary Adcock got the meeting off to a very fast start, discussing PDF export options from InDesign. He showed an interesting arrangement of colored shapes using transparency, feathering, blend modes, and a drop-shadow or two. What I loved most about the demo art is that it perfectly matched the light colors (cyan, red, yellow, gray, etc.) and rectangular shapes of Gary’s wonderful color-blocked shirt!
Back to the show. In the Style pop-up menu at the top of the Export PDF dialog, you have four presets in the default General panel: [eBook], [Screen], [Print], and [Press]. But what are you actually getting with these presets? Let’s choose [Print]. Sounds good, right? Well, right and wrong. It will print fine to a high-res imagesetter (good), but your client won’t like it as a proof because it will print as it looks on screen to a laser printer — with its flaws. What flaws? (This InDesign document was constructed to test the limits of transparency. Some of the blending modes used are not recommended for use with spot-colors because they display differently on screen compared to how they will output.) Go to the Advanced panel of the Export PDF dialog and you'll see that for transparency flattener style, [Medium Resolution] is the default setting. Ah, bad. So what does it mean to choose [Medium Resolution] or [High Resolution]? For print applications, use [High Resolution]. That sounds reasonable, but what do these settings really involve? More than just resolution. These presets are labels for groups of settings — some good, some not so good — for print applications.
Check it out by choosing Edit> Transparency Flattener Styles — InDesign’s method for ensuring that transparency (i.e., using opacity setting and blend modes from the Transparency palette, or applying a drop-shadow or feathering to a selected object — live text, shapes, imported bitmaps, anything) outputs correctly from InDesign (assuming correct settings). Low and behold, in the Transparency Flattener Styles dialog, there we have the three presets that appear in the Advanced panel of the Export PDF dialog. But here, when we set up these flattener styles, we can see just exactly what the specific settings are for each of these labels. Flattener styles are also available in the Print and EPS dialog boxes, and are available only in the Export PDF dialog when Acrobat® 4.0 is chosen.
Let’s start by clicking the [Low Resolution] setting, then New…, to see what that holds in a second dialog. InDesign’s “Help” system says: “Use for quick proofs that will be printed on black-and-white desktop printers, and for documents that will be published on the Web or exported to SVG.” We’ve got the Raster/Vector Balance slider bar that goes from “Rasters” on the left (call that #1) to “Vectors” on the right (#5), with three mysterious unlabeled tick marks in between — #2-3-4. For the low-res setting we’re examining, the slider is on #4. Flattener resolution is set to 288 and gradient resolution to 144. Force Text to Outlines and Clip Complex Regions is unchecked, while Convert Strokes to Outlines is checked.
Now go back and choose [Medium Resolution] instead. “Help” says: “Use for desktop proofs and print-on-demand documents that will be printed on PostScript color printers.” Remember, if all you did in the Export PDF dialog is choose [Print], a seemingly reasonable choice, you’re going to get the medium-res package of choices. And here they are: The slider is on #4, just like for low res! Flattener resolution is at 300 and gradient resolution is at 150, so those numbers have gone up a negligible amount from low. Clip Complex Regions is now added to the checked boxes. Hold your breath — we’ll let you know what the story is, but first let’s look at the high-res setting.
Return once again with “Cancel,” and then click [High Res] to see what we’ve been missing when we choose [Print] in the Export PDF dialog. “Help” says: “Use for final press output, and for high-quality proofs such as separations-based color proofs.” Here the slider is finally on #5 — all the way to pure vectors, no raster. Flattener res is set for 1200 and gradient res is set for 300 — significant increases from low and medium. And now only the Clip Complex Regions box is checked. Convert Strokes to Outlines is unchecked for the first time.
OK, OK, so what does this all mean? Let’s export this multicolor, multi-transparent-effects file using the default [Print] PDF setting, which uses the [Medium Resolution] preset under Flattener Style. Open it in Acrobat Reader and you’ll see some white lines that weren’t in the original art. Where do these come from? Go to Acrobat 5.0’s Display Preferences settings and you see the setting Smooth Images. It’s checked. Whoa, this Acrobat preference is the culprit. If turned off, your PDF file exported from InDesign will look great on screen, just as it looks in InDesign, and your client will be happy. But if Acrobat’s default Smooth Images setting is checked, you may see white lines in your art — which clients won’t go for (understatement). The old adage, “What you see is what you get”? In this case, not true. It is just a display issue — prints fine to high resolution, though not fine to the laser proof your client might see, causing him or her to go nuts. If your client uses Acrobat 5.0 (and not Reader), he or she can turn on View> Overprint Preview and the display problem will also solved. Either way, you gotta tell your client how to view this PDF.
From Matt
Now Matt comes to the podium, with his soft-spoken understated voice and solid black colorless Adobe shirt — but as the engineer, he knows the goods!
But let’s get down to basics (my suggestion). In the Flattener Transparency dialog, for print applications, skip all tick marks in the Raster/Vector Balance slider bar except #5 — i.e., the full-throttle vector-only setting on the far right — by far your best choice. But you may see some long print times with this setting and may have to compromise on one of those 2-3-4 settings — the higher the better. With full raster, #1 at the far left, you get the fastest performance (print time), but nearly all elements are converted to raster — not recommended. As you move to the right on that slider, print times go up but more vectors are maintained. So why the heck do we need flattener styles in the first place? Because PostScript® doesn’t understand transparency. (No kidding, that was a revelation!) We have flatteners in Illustrator® 10.0, Acrobat 5.0, and InDesign 2.0. The flattener takes a document that has transparency and produces a nontransparent document that looks the same as the original.
The flattener calculates all the intersections of two overlapping shapes, when at least one of those shapes has some kind of transparency. It makes a third shape of the overlapped area — these are called “atomic regions.” This process is very much the same as using the Divide pathfinder in Illustrator. But it’s a “very tricky piece of code.” When you choose the full vector choice (#5), you get no anti-aliasing, those softened pixels at the edges to camouflage square pixels. And you surely almost never want the pure raster choice #1. The three middle stops are “safety valves for slow systems.”
With the full vector setting (#5), Clip Complex Regions is a nonissue (i.e., shapes are automatically simplified by how they are divided and broken down into atomic regions). And also, with full vectors, you don’t need to worry about the 1200-dpi setting for flattener resolution — that setting comes into play only when your slider is on #1 through #4, where rasterization is taking place.
The flattener resolution is used for lines, bitmaps, and type that are involved with transparency — if they’re transparent or interacting with other objects that are. Avoid problems with text interacting with transparency by making sure your text is on top (stacking order or top layer) or getting it as high in the layer order as possible so it doesn’t rasterize (with settings less than #5). If you do need to use a raster setting (#1 through #4) and have (one-color) line art on your page, then by all means use the 1200-dpi setting for flattener resolution.
Bottom line: Choose the [High Resolution] setting for flattener style and you’ll be fine.
Note: InDesign’s “Help” says flattener resolution is for all rasterized artwork except gradients.
As for the gradient resolution setting with flattening, when you have a gradient with transparency, the gradient must be rasterized, even with the all-vector setting on the slider. And when you use drop-shadows or feathering, you will involve that gradient resolution setting also. Matt recommended a gradient res of 150 to 300 dpi: 150 is fine, and 300 offers best quality.
InDesign’s “Help” system says: “Note: The amount of rasterization that occurs depends on the amount of RAM available to the program, the complexity of the page, and the types of overlapping objects.”
Back to the “smoothing” choices in Acrobat preferences. Matt said that checking all three options (Smooth Text, Smooth Line Art and Smooth Images) will ensure that text that’s been converted to path outlines (Type> Create Outlines in InDesign) looks better in PDF. Type gets converted to paths automatically with flattening if your type has a blend mode or is on a lower layer and interacts with transparency.
When you export to PDF from InDesign 2.0, as Acrobat 5.0 or 6.0, the file is not flattened, because PDF supports transparency.
Back to Gary
Gary showed us that instead of externally linking your placed images, you can embed them from InDesign’s Links palette menu (“Embed File”). Then later in InDesign or Acrobat they can be unembedded and they’ll be in the same shape as they were originally. (From the Links palette in InDesign or in Acrobat 5.0: - File> Export> Extract Images As> JPEG/PNG/TIFF.) This can be a handy way to send files and keep everything together if you don’t have a lot of large images. But you can’t unembed fonts, of course.
Gary also pointed out that in the Advanced panel of the Export PDF dialog, you have the Color > Leave Unchanged setting — what you should use if you have both spot-colors and process colors. Matt mentioned that InDesign never automatically converts a spot-color to process. Gary said that 60% of PMS colors printed as CMYK conversions will yield unacceptable results. Only 40% of the spot-colors will be fine when you check All Spots to Process in InDesign’s Ink Manager. Matt said that by checking Simulate Overprint, also in the Advanced panel, you’ll get a virtual press proof with your composite printer because it will “sandwich together the four CMYK layers on top of a white substrate.”
Dorothy Mason asked about the CMYK preview in InDesign. She verified that even though your monitor may not be calibrated, just turning on this preview lets you see which colors shift as they change from their RGB display to a display based on CMYK.
After the break, James Wamser of Sells Printing showed many wonderful samples of transparent and densely layered images output at Sells and printed on its presses. He’s been trouble-shooting InDesign files from the start and has “seen it all.”
