What is an acceptable common resolution for print and online?

[Verner A]

We are converting xlm files to pdf through Tridion Docs and DITA open toolkit. So far the pdf file has only been used for printing manuals. Now the pdf files are also to be accessed through a web server. The content is black and white text, line drawings and a few black and white drawings.

We want to reduce the size of the pdf output to reduce the time it takes to open from the web server.

What is an acceptable size. Are there specific settings that I should tweak?

[Test Screen Name]

There is really none. Print files are too large for online use, and online files are too poor for print use. Trying to find a common path will please nobody. Your workflow needs to generate two files. You can also use things in the online version like links in colour, which don't appeal in print.

[try67]

With the current download speeds and storage capacity of almost all devices putting a print-quality version online should not be an issue.

[Abambo]

Professional printing services recommend 300 dpi. However less may be acceptable. If your docs contain vector graphics, it's anyhow a no-brainer. Vector graphics are always printed at an optimal resolution as the rendering is done in the printer engine.

[Verner A]

When I added a table with 6 screen captures each taking up 6 kb the size of the pdf file rose from 4.7 to 7.6 MB. So maybe I can change the rendering of pdf grahics in the DITA open Toolkit/Antenna House?

[Abambo]

You will need to tweak the parameters to produce the smallest file possible that gives you a result that is still acceptable. Generally for the web, compression and resolution is reduced. If you are doing mixed application (print and display) you need to trade of for quality and size. I tweak my parameters and create a joboptionts file and distribute that to the users, so that the PDF creation is best quality and lowest size for the chosen use.

[JR Boulay]

Unlike a stubborn old legend, it's not the resolution that causes the weight of a file: it's the compression formats used.

You should try to optimize your files with JPEG2000 compression, quality Medium or Low.

If prepress files are huge, it is mainly because graphic designers and printers have a sickly and irrational fear of compression.