Exporting to PDF, large files

[Daisy_Edwards@adobeforums.com]

I'm a student and have started using In Design 2.0 in Windows XP to create dome documents for my assignments, which involve a lot of text and images. Whenever I export my files to PDF format, they are always extremely large and take a lot of time to export and print. I don't know if I'm not using the right export functions, or if the image files are too big to begin with, but my files are getting up to 16 mb for a 20 page document. In my ming this is a large file, especially since I've seen files on the internet 60 pages long and about 2mb in size.
Any help is welcomed,
Thank you.

[Robert_Levine@adobeforums.com]

A graphics intensive document with high res photos could easily be that
large or even larger. What is the PDF going to be used for (screen,
print, press)?

What are your export settings?

Bob

[Gabriel_Ayala@adobeforums.com]

Fist of all, how did you aquire these images?

If these are going to be PDFed to be viewed on screen as described in your "since I've seen files on the internet 60 pages long and about 2mb in size" statement you need to scan the originals at the proper resolution.

Along the way, you may have learned from other students or teachers that the best thing to do is scan all photos at 300 DPI. This is not so!
Lets suppose you have an 8X10 photo and you plan to place the picture into your document at a size of about 3X4. If you have Photoshop, you could get away with scanning this photo at only 50 DPI and you would still have plenty of clarity.
I would Scan the Photo at 50 DPI and shrink the image size but increase the resolution to about 130 in photoshop to keep your image looking clean enough for viewing on screen. This would give you a image file about 1MB in size. Even 130 is more than plenty for screen. Screen is usually 72 DPI so go figure.
OTOH if you had scanned the photo at 300DPI and changed the size but left the resolution alone, you would have a super clean image but it would be overkill and the image file size would be about 4 times bigger.

The AcrobatDistiller settings should take care of the final PDF size depending on the compression level and such but I was just trying to point out a common mistake I've seen students make all too often and I'd like you to steer away from unecessary bloating of files.

Another thing you can do to keep your files smaller in size is to use the Save As command instead of just plain Save. If you use Save As, you eliminate unecessary bloating too. This goes for InDesign and Acrobat.

[Daniel_Choe@adobeforums.com]

You can greatly affect the size of your PDF by adjusting the downsampling size of your images (compression settings).