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Mastering CorelDRAW 9

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Objects

As its name implies, the second page of the dialog is where you determine how DRAW handles the various objects in your document.

Bitmap Compression

DRAW offers three choices for how to handle embedded bitmap images: None, which is, well, none; LZW, a lossless compression algorithm; and JPEG, a lossy method.

You can probably guess what the difference is between these two curious-sounding options. With lossless compression, DRAW will compress bitmaps as much as it can without throwing away any data. Lossy, on the other hand, will generally return the smallest file sizes, but data will be removed. Depending on the amount of compression, the result could be a visible loss of quality.

Weighing the benefits of small sizes vs. high quality is up to you, and the final resting place of the PDF file is perhaps the most important consideration. For example, files destined only for onscreen viewing do not require images with fidelity as high as if they were to be used for generating film and plates for commercial printing. A general rule of thumb is to use JPEG compression for screen and Web files, and LZW for everything else. (We can’t think of a reason to choose None, unless you’re entered in a contest to create the largest possible PDF file.)

PostScript files through Adobe Distiller to PDF are marginally smaller than DRAW 9’s PDF files, due to the differences in compression methods. DRAW 9 uses JPEG for lossy and LZW for lossless. Adobe also uses JPEG, but instead of LZW, it employs ZIP compression, which does generate somewhat smaller files. In either case, however, when you choose lossless compression, you will see no degradation of bitmap images.

Bitmap Downsampling

Bitmap Downsampling gives you the option to reduce the resolution of any bitmaps in your document, which in turn reduces the overall size of the PDF file. You can downsample all color, grayscale, or black-and-white bitmaps; only color, grayscale, or black-and-white bitmaps; or any combination thereof. The Downsampling and Compression options sound related, but technically speaking, they are not. A downsampled image might not look as good as the same one at full resolution, but it is not due to the arbitrary removal of pixels. It is the result of the entire image being converted to a lower resolution. If both options are enabled—downsampling and compression—bitmaps will be downsampled before being compressed.

As mentioned earlier, the PDF format allows true one-document-multiple-destination output. Bitmap Downsampling is one of the options available to you to achieve this end. If you have created a document originally destined for commercial printing, any included bitmaps will be high resolution—overkill for screen graphics. The solution is to keep your original DRAW file intact and only adjust Bitmap Downsampling as appropriate.


NOTE Some of the preset styles include bitmap resolutions we disagree with. For example, the Web style has Bitmap Downsampling set to 120dpi. We would change this to 96dpi. And, we see no reason for most prepress work to ever downsample to more than 200dpi.

Text and Fonts

Another intimidating list for the uninitiated, but don’t worry, your eyes will uncross with a few simple explanations and recommendations.

Export All Text As Curves Choosing to export all text as curves means first and foremost that the text in your PDF file will not be editable. Since one of the benefits of the PDF format is the ability to make minor adjustments and edits on the fly, and to copy and paste text from PDF files into other documents, we do not recommend using this option except for extreme circumstances of unusual text characters. Converting text to curves will also increase the complexity of the file, resulting in larger file sizes and increased RIP time. However, if you are using a customized typeface, or some strange TrueType face, exporting as curves ensures that it will be seen the way you intended. This is not unlike the Separate or Convert to Bitmap commands that freeze DRAW’s effects in their tracks.

Embed Fonts in Document Embedding fonts in the file means that What You Want to Give Them Is What They Get. Without embedded fonts, the PDF engine substitutes what it thinks is the closest match to the font you used to create the text. Often the substitution is not even a close match, and your design integrity is lost. Embedding fonts is the best choice for generally all PDF files you will publish. Exceptions can be made if you are absolutely certain that the recipient has exactly the same fonts loaded on their system, but you know what?—it’s not worth it. Just embed them.

Embed Base 14 Fonts All PostScript output devices have 14 base fonts (PostScript, of course) available at all times. However, over time some of these fonts have evolved into slightly different versions. If you use one of the base 14 fonts in your document but do not embed the base 14 fonts into the PDF, the PostScript device will recognize the call to the font in the PDF and will substitute its version. Chances are you will never notice a difference, but, for example, if your copy of Helvetica is slightly newer than the Helvetica resident on the service bureau’s imagesetter, your letter spacing may change and your text may reflow.

Again, don’t take the chance—it’s not worth it. Embed the base 14 fonts when you are heading to a service bureau for film or high-resolution output. For Web output, font embedding is a moot point, and you should uncheck this option and save a bit of file space.

Convert TrueType to Type 1 If you use TrueType fonts in your document but do not check the option to convert them to Type 1, they will be converted to curves when you publish to PDF. While you will not notice a difference by looking at the final output, the inclusion of many TrueType fonts converted to curves will substantially add to the complexity of the file, and the recipient will not be able to perform any edits to that text in the PDF file.

Converting TrueType to Type 1 means that the fonts will be embedded in the PDF (if you choose to embed fonts) and the recipient will be able to edit the type. However, it also means that file size will increase substantially if you have used a lot of TrueType fonts. If file size is of less importance than file integrity and editability, then enable this option. We recommend always using this option.


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