Copy-and-Paste vs. Place

Michael Murphy

35

While I’m getting my next (overdue) videocast finished, I’ve been answering a lot of questions by e-mail, so I thought I’d step out of my little corner of InDesignSecrets.com and contribute one of these answers to the blog.

Brendan said:

“I have a inherited a job where I need to cut and paste photographic images from existing Illustrator .eps files (the photos are embedded, no links) into an InDesign file and would like to have a greater understanding of what effect this may have upon the image once it is pasted into the InDesign file. ie., will there be any loss in quality, resolution, colour-space, etc.”

If you’re copying and pasting from Illustrator, you are effectively disassociating the graphics from their Illustrator origins. Vector art copied from Illustrator and pasted into InDesign becomes an InDesign object (or object), making it fully editable from within InDesign, and no longer linked in any way to the original Illustrator file.

If you’re copying and pasting embedded photographic images from Illustrator into InDesign (which I’m not quite sure why you would…but I’ll address that below), you are bringing all of the image data into InDesign. A way to confirm this is to use the built-in Preflight function (Shift-Command-Option-F on the Mac / Shift-Ctrl-Alt-F on the PC), which will give you information on the attributes of the pasted image. A copied image pasted into InDesign is automatically embedded. The screen shot below shows that. Notice that the image has an “effective ppi” of 225 pixels per inch.

This image shows up as CMYK because the Illustrator file from which it was copied used a CMYK color space. If it had come from an Illustrator EPS file with an RGB color space, it would have retained the RGB attributes, and been flagged as such by InDesign’s preflight function.

If this is the working method you need to use, the preflight function will be a good way to double-check that you’re getting into your document the type and quality of image you’re looking for.

However, I have to ask: why copy and paste these images into InDesign? Why not just place them using the Place command? There are two distinct advantages to this:

First…file size. Each image you embed increases the InDesign document’s file size by whatever the size of all that image data is. In a very short time, your InDesign document could be unmanageably large. I did a test of a 5″x 7″ image at 225 pixels per inch and the embedded version resulted in an 8.8 MB InDesign file, but by using File –> Place to import the Illustrator EPS image made only a 1.2MB file.

Second…what if something were to happen to your InDesign file? Suppose it gets corrupted, deleted, or otherwise lost. All of your images are gone with it. You’re faced with the task of re-copying and re-pasting the images from the original EPS files (provided you still have them).

While you’re not losing any quality in your images with the method you describe, I recommend re-thinking the workflow for better efficiency. Either just place the images from the original EPS files, or better yet, get them out of Illustrator altogether and into Photoshop. Personally, I prefer to keep my bitmaps and vectors in their respective applications. It helps me mentally organize them better. I see a Photoshop file, and I think raster image. I see an Illustrator file, and I think vectors. I know there’s crossover (vectors can exist in Photoshop and images can exist in Illustrator), but I’m a fan of keeping things simple.

Brendan also had concerns about this statement from the InDesign Help file:

“When copying and pasting a graphic from another document into an InDesign document, InDesign does not create a link to the graphic in the Links palette. The graphic may be converted by the system clipboard during the transfer, so both image quality and print quality may be lower in InDesign than in the graphic’s original application.”

The key phrase in this is “may be.” There are issues to be aware of. For instance, if I copy a 5″x 7″ high resolution image out of an Illustrator EPS file and want to pasted it into a new Photoshop file, Photoshop will use the clipboard information for the physical size of the image (5″x 7″), but it will us its previous pixel-per-inch values when a new Photoshop image is created using the default “Clipboard” setting in the New Document dialog box.

Therefore, if the last Photoshop image I created was 72 pixels-per-inch, Photoshop will want to make the 5″x 7″ image in the clipboard into a file at that resolution, instead of 5″x 7″ at its actual resolution. So, yes, under some circumstances, you may be subject to the whims of clipboard and other system functions. All the more reason to avoid the copy-and-paste method…just to be safe.